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1. 254 2373n 4 757869u lt 4 503632u gt 40 t i l i l i l i 30 t l i i 20 T t i i i 10 i l i i l i i i i 101 T H l i 201 1 94 3299m i B0 soar N neal eine EAE E E V 292 533m i i l i goote 4 386 863m Reference i i Cursor 0 0 5 1 15 2 25 3 35 4 45 Time uSecs 500nSecs div Main Cursor 242 Chapter 9 Graphs Probes and Data Analysis The cursors can be moved horizontally or vertically while tracking an attached curve or they can be picked up and dragged onto another curve Initially there are just two cursors but there is the facility to add additional cursors without any maximum limit Cursor Operations Displaying To switch on off the cursor display select the graph menu Cursors Toggle On Off Moving Cursors can be moved by any of three methods Left to right In this mode the x position of the cursor is varied while the cursor tracks the curve to which it is attached To use this method place the mouse on the vertical crosshair but away from the intersection with the horizontal crosshair You should see the mouse cursor shape change to a left right arrow Press left mouse key and drag 2 Up down Similar to 1 above but instead the y position is varied To use this method place the mouse on the horizontal crosshair but away from the intersection with the vertical crosshair You should see the mo
2. These devices are implemented using the simulator s ADC and DAC models For details of these refer to the chapter Digital Mixed Signal Device Reference in the Simulator Reference Manual The controls in these boxes are explained below Number of bits Resolution of converter Values from 1 to32 Convert time ADC Time from start convert active rising edge to data becoming available Max conversion rate ADC Max frequency of start convert Period 1 f must be less than or equal to convert time 141 User s Manual 142 Output slew time Whenever the input code changes the output is set on a trajectory to reach the target value in the time specified by this value Offset voltage Self explanatory Range Full scale range in volts Generic Digital Devices A number of generic digital devices are provided on the Place Digital Generic menu Each will automatically create a symbol using a basic spec provided by your entries to a dialog box Functions provided are counter shift register AND OR NAND and NOR gates and bus register Functional Blocks Overview The simulator supports a number of devices that are arbitrary in nature and which are used to define a device in terms of its function or behaviour Functional blocks have a number of uses Here are two examples 1 System level simulation You are investigating the viability or characteristics of a complete system before actual
3. 6 As before press F3 then select Measure Transient Mean Cursor Span The new peak power cycle will now be in the 11 12W region much more than before 48 Chapter 2 Quick Start Tutorial 3 Installing Third Party Models In this tutorial we will install a device model library For this exercise we have supplied a model library file TUTORIAL3 MOD with just two devices These are SXN1001 an NPN bipolar transistor SXOA1000 an opamp Both are totally fictitious You will find this file in the tutorial folder i e Examples Tutorials Tutorial3 mod There are two aspects to installing a model SIMetrix needs to know where within your file system the model is located If the model is to be listed in the parts browser system then SIMetrix also needs to know what symbol to use for it in the schematic and what category it comes under This is how you do it 1 Open windows explorer or click on My Computer or open other file manager of your choice 2 Locate TUTORIAL3 MOD in EXAMPLES Tutorials see Examples and Tutorials Where are They on page 32 Pick the file up and drop into the SIMetrix command shell That is drop it in the window where SIMetrix messages are displayed If you can t see the command shell because it is obscured select any SIMetrix window then press the space bar A message box will appear asking you to confirm you wish to install the file Click Ok The message Making device ca
4. eeeeeeeeees 143 Table of Contents Laplace Transfer Function ceeessceeeeeeeeees 145 Arbitrary Non linear Passive Devices 00 146 Creating Models eee eeeecesesteeeeeeeeeenneeeeeeeeeenneeeeeaes 147 OVGIVIOW nisn ese he ee eee ee 147 Creating Soft Recovery Diode Models 147 SUBCIFCUITS iora i eii iiaa aida iiaei 149 OveNIEW osati eiia a 149 Creating a Sub circuit from a Schematic 149 Calling a Sub circuit in a Schematic ee 151 Special COMPONENS eee eeeeeeeeeeeeeeeeeeeeeeeeeeneeeeeaes 153 Initial Conditions 0 0 eee eect ence eeeeeeeeeeeeeeeaeeeeeas 153 NOdeSCtS s reieun eaa E E AEAT aani Ee 153 E AEE E E E E 154 Parameters and ExpresSions ccccceeeeeesteeeeeeeees 154 EXampless lt 2ssstiitia date Sethian 8 ieee aed ete 154 Chapter6 Device Library and Parts Management Using Parts BrowSer eeccecseeeseeeeeeneeeeseeeeeeneeeeeeees 157 Parts Management Installing Models eee 158 OV6INVIEW nee aia Se Sea 158 PROCCC UC saninin ete neia nan nE iain 158 Full Model Installation Procedure seee 158 Removing Model Libraries ccececeeeeeeeeeee 161 Parts Management Advanced TOpics eseeees 161 Associating Multiple Models with Symbols 161 Embedded Association 163 Catalog FES nig ei etai 164 Importing Models to a Schematic cee 165 SUNY TOPICS ninien ated eii a 165 LIB Con
5. 10m AC 1 0 restail R2 USUB Transfer function frequency sweep The results Series qode gain Gain from V2 to output Common mode Gain from V1 to Output 100k 1M 10M 100M Frequency Hertz 190 1G Chapter 7 Analysis Modes All of the above waveforms were created with a single analysis Pole zero Pole zero analysis is a small signal analysis mode that as the name implies locates the poles and zeros of a circuit Note that circuits containing transmission lines or any of the Philips compact models are not supported IMPORTANT Pole zero analysis is an unsupported mode This means that we cannot provide assistance in its use nor will we be able to resolve any problems found with it We may withdraw Pole zero analysis from future versions of the product Setting up a Pole zero Analysis Place a control of the following form in the F11 window PZ NI N2 N3 N4 CUR VOL POL ZER PZ Where N N2 are the input nodes and N3 N4 are the output nodes CUR means the transfer function is of the type output voltage input current while VOL means it is output voltage input voltage Usually the last parameter would be PZ which instructs the simulator to find both poles and zeros The alternatives instruct it to find one or the other This may be used if the simulator aborts because it didn t converge on poles or on zeros at least it can be instructed to find the other
6. mG Sel Current mouse mode Magnification 93 User s Manual 94 The Elements of a Symbol Schematic symbols are composed of a combination of the following elements All symbols that represent an electrical device would comprise all of these elements Symbols used purely for annotation would not need pins and may not need one or other of the remaining elements either The schematic caption for example is a symbol that consists purely of properties Segments These make up the visible body of the symbol They include straight line segments and arc segments Pins These define electrical connections to the device 7 Properties Properties have a name and a value and are used to define the behaviour of the device represented by the symbol They can also be used for annotation for example a label or a caption Creating a New Symbol Select the command shell menu File Symbol Editor New Symbol This will open a symbol editor window as shown above Now create the elements of the symbol as described above Details are provided in the following sections Editing an Existing Symbol Select the command shell menu File Symbol Editor Symbol Manager and select the symbol you wish to edit See Symbol Library Manager on page 114 for details If you wish to edit a symbol that is placed on an open schematic select the symbol on the schematic then choose popup menu Edit Symbol Drawing Straight
7. Using symbolic constants SIMetrix has a facility to define path names using symbolic constants This system allows absolute locations for files to be defined using a single value and thus making it easy to change that location See Symbolic Path Names on page 321 for further details Chapter 4 Schematic Editor Connecting Busses in a Hierarchy Overview Bus connections can be passed through a hierarchy in much the same way as normal single wire connections Bus connections are defined by the underlying schematic The symbol representing the schematic does not require any special treatment Creating Bus Connections Using the Bottom Up Method 1 Enter the schematic in the usual way 2 To define a bus connection place the part Hierarchy Place Module Bus Port instead of the usual Module Port Select the device and press F7 to define the port name and bus size i e the number of wires in the bus 3 Save schematic as a Component 4 Select menu Hierarchy Open Create Symbol for Schematic 5 Edit symbol if required then save Changing the Bus Offset in the Parent Schematic The bus connection in the parent schematic has a size that is determined by the module port in the child schematic However the offset that is the first wire it connects to in the bus in the parent can be changed on a per instance basis To do this proceed as follows 1 Select the label next to the bus pin This will be of the form A B where A
8. Viewing Results Select the command shell menu Simulator List Pole zero results The poles and zeros will be listed in complex form Example An example circuit that is already setup is provided in Examples Pole zero simple_amp sxsch Also provided is another circuit containing a Laplace block defined from the results of the pole zero analysis This circuit can be found at Examples Pole zero verify_pz sxsch The example demonstrate a method of verifying the results and also an application for pole zero analysis The application is a method of modelling a complex circuit as a small signal block First run a pole zero analysis to locate the poles and zeros then build the laplace transform from them The laplace transform can then be entered into the Laplace block Note that pole zero analysis does not provide the gain of the circuit This will need to be evaluated separately perhaps using transfer function analysis Sensitivity This control instructs the simulator to perform a DC sensitivity analysis In this analysis mode a DC operating point is first calculated then the linearised sensitivity of the specified circuit voltage or current to every model and device parameter is evaluated The results are output to a file SENS TXT by default but can be changed with SENSFILE option and they are also placed in a new data group The latter allows 191 User s Manual the data to be viewed in the message window type Display at the command
9. Returns the real part of the complex argument Ref real complex Returns the reference or x values of the argument 309 User s Manual 310 Rms real Returns a vector of the accumulative RMS value of the input Unlike RMS1 this function returns a vector which can be plotted RMS1 real real real Vector Start x value Default start of vector End x value Default end of vector Returns the root mean square value of the supplied vector between the ranges specified by arguments 2 and 3 If the values supplied for argument 2 and or 3 do not lie on sample points second order interpolation will be used to estimate y values at those points rnd real Returns a vector with each element a random value between 0 and the absolute value of the argument s corresponding element RootSumOfSquares real real real Vector Start x value Default start of vector End x value Default end of vector Similar to RMS1 function but returns the root of the sum without performing an average sign real Returns if argument is greater than 0 otherwise returns 0 sin real complex Return sine of argument in radians Use sin_deg if the argument is in degrees sqrt real complex Returns the square root of the argument If the argument is real and negative an error will result If however the argument is complex a complex result will be returned SumNoise real real real Identical to RootSumOfS
10. The smart wiring algorithm use an heuristic algorithm that finds as many routes as possible then chooses the best one based on a number of criteria The criteria used in the selection include the number of corners the number of wires crossed the number of property labels crossed and its overall length It attempts to find the most aesthetically pleasing route but as this is somewhat subjective it may not necessarily find the route you may have chosen manually However in our tests we have found that it usually finds the best route for situations where there are no more than 2 or 3 corners required In developing the algorithm we paid particular attention to common scenarios found in analog design such as routing the output of an opamp back to its inverting input and you should find that these common scenarios work well Smart Wiring Options There is two option to control the smart wiring algorithm Firstly you can disable the smart wiring algorithm altogether in which case the smart wiring procedure will place wires in a similar fashion to the manual wiring methods Secondly there is an option that controls whether or not the smart wiring algorithm is allowed to route wires through existing wires that are connected to the start and end points By default this option is on i e the smart algorithm is allowed to route through connected wires If the option is off the algorithm will not allow any wires in the route to connect to any existin
11. This is not the case with the other device in the model library This is an opamp and is defined as a subcircuit This is a module made up of other components in this case BJTs diodes resistors and current sources SIMetrix can t tell what type of device this is It knows that it has five terminals and it knows where the electrical model is located in the file system but it doesn t know what schematic symbol to use for this model SIMetrix will ask you for this information when you try and place it Follow this procedure 1 Repeat the steps 1 5 above but instead select the SXOA1000 device instead of the SXN1000 Notice that when you select the device in the right hand side you see the message SIMetrix does not know what symbol to use for this model Press Place to resolve Chapter 2 Quick Start 2 After pressing the Place button you should see the following box e Associate Symbol with Model SXOA1000 STEP 1 Select a suitable category for this part If you can t find one press New Category Unassigned and enter a new category of your choice STEP 2 Select a suitable symbol for this part Select a symbol from the drop down box or press Auto Create Symbol to create a new one AD567 If selecting an existing symbol you must make Pin order sure that the pin order matches the model definition shown below Press Help for assistance If you use Auto Create Symbol the pin order will not need
12. Transient Analysis cceeeeseeeeeeeeeeeeeeenneeeeeeeeenneeeee 201 Setting up a Transient Analysis ceeee 202 Periodic Operating Point POP 203 Setting up a POP Analysis 0 0 0 0 ee ceeeeeeeeeeeeeereeees 204 AC Analysis neiaa a tai 205 Setting up an AC Analysis 0000 ei eeeeeeeeereeeeeneees 205 SIMPLIS Options eee eeeceeeeeeseeeeeeneeeeeneeeeenaeeeeenees 205 Multi step and Monte Carlo Analyses ceseeeeeees 206 OVENVIEW E E hdeeeeesetescd Goi Mawes eaten 206 Comparison Between S iMetrix and SIMPLIS 206 Setting up a SIMPLIS Multi step Parameter Analysis206 Setting Up a SIMPLIS Monte Carlo Analysis 208 Tolerances and Distribution Functions 0 208 Performance Analysis and Histograms 209 Initial Condition Back annotation 0 ec eeeeeeeeeteeeerees 209 OVGINVIEW 8 iene ide i ei 209 How to Back annotate a Schematic ee 210 Disable Enable Initial Conditions eee 210 Back annotation Errors c cccceseeseeeeeeeeeeeeeeees 210 Editing Back annotated Initial Conditions 210 How Does it Work ccccceececeeeeeeeeeeeeeseteeeeeeeees 210 Hierarchical Blocks and Subcircuits 0 0 0 211 Chapter9 Graphs Probes and Data Analysis Elements of the Graph Window ccceesseesteeeeneees 212 Main Window ceeecceeesseceeneeeeneeeeeeneeeseaeeenneeeeeaa 212 Windows and Tabbed Sheets 212 Graph T
13. You can only edit the names of pins one at a time but you can edit the attributes of a group of pins in a single operation First select all of the pins you wish to edit Selecting is done in the same manner as for the schematic except note that you can select the pins themselves or the pin names either will do Now press F7 or select popup menu Edit Property Pin Arc You can change any of the pins attributes except its name and the change will be applied to all selected pins Moving Pins or Pin Names Moving any item in the symbol editor is done the same way as in the schematic Note however that pin names are attached to the pins If you move a pin its name moves with it You can move the name on its own by making sure that only the name is selected and not the pin Defining Pin Order The symbol s pin order is important if you are defining a symbol for use with a sub circuit or primitive simulator device If it is a sub circuit the symbol s pin order must Chapter 4 Schematic Editor match the order in which the corresponding nodes are defined in the SUBCKT control If the symbol is a primitive device then it must follow the order defined in section Summary of Simulator Devices on page 122 Pin order is unimportant for hierarchical blocks To define the symbol s pin order select menu Property Pin Edit Pin Order Use the up and down buttons to reorder the pins as appropriate Adding XSpice Pin Attributes Some XSPICE
14. are aborted if any individual command reports an error If on a warning rather than an error is given if an unknown device model parameter is found The simulation will continue if there are only warnings but will not if there are errors Default sxappdatapath user Location and base name without extension of user catalog file used by versions 5 2 and earlier This file is used to populate the current user catalog file Default false If true the revision value is not written to ASCII schematic files For backward compatibility If set the Welcome dialog box is opened on startup User interface support Options dialog Options dialog Options dialog No Check box in Welcome dialog Chapter 13 Sundry Topics Name Type Description User interface support PassUnres Template Boolean Default false No If true unresolved template unsupported values in netlists will be passed literally Default behaviour is no output Precision Numeric Default 10 No Precision of numeric values displayed using Show command PrintOptions Text Options set in print dialog Print dialog PrintWireWidth Numeric Default 5 No Width in pixels of schematic wires when printed ProbeStartDelay Numeric Default 1 Options Delay after start of dialog simulation run before fixed probe graphs are first opened ProbeUpdatePeriod Numeric Default 0 5 seconds Options Update period for fixed dialog probe grap
15. 0 ee eeeseeeeeeeeeneeeeeeaes 312 Chapter 12 Monte Carlo Analysis An Example o c csececceqeeceteccensecesesdeetensessdesonencrsterspeneetes 313 Component Tolerance Specification ec eee 315 Setting Device Tolerances cccceeeeeeeeeeeees 315 Model Tolerances sssini vinnin 316 Matching Devices cccccececceeeeeeeeeeeeeeeeeeeeeeeeees 316 Random Distribution eee eeeeceeeseeeeeeeeeeeneeeeeee 317 Running Monte Carlo ececeeseeeeeeeeeeeeeeeennaeeeeeeees 317 OVE IVIGW EEE E 317 User s Manual Chapter 13 14 Setting up a Single Step Monte Carlo Sweep 317 Setting up a Multi Step Monte Carlo Run 318 Running a Monte Carlo Analysis 318 Setting the Seed Value 318 Analysing Monte Carlo Results 00 eeceeeseeeesteeeeneees 319 Plots is eon er a N erea 319 Creating Histograms eneee 320 Sundry Topics O EEEE E 321 Defio Mairs ineitn r inper cuter ede 321 Configuration File Example secese 322 Using Symbolic Names eee eeeseeeeeeeeeeeneeeeeees 322 SlIMetrix Command Line Parameters eee 323 Using Startup ini atcerei 324 Configuration Settings ee eeeseeeeeseeeeeeeeeeesneeeeenes 324 OVE IVIOW E E 324 Default Configuration Location 324 Application Data Directory 325 Specifying Other Locations for Config Settings 325 OPT OMS casei fas cs ants oaeiae ecteip bean tects araa aes eae 325 OVOIVIOW iiinis iine aei Heelies ede ciel
16. Continuous Fourier does not require the data to be interpolated and does not suffer from aliasing The problem with continuous Fourier is that compared to the FFT it is a slow algorithm and in many cases an FFT with a very large number of interpolated points can be calculated more quickly and give just as accurate a result However in cases where a signal has a very large high frequency content such as narrow pulses this method is superior and it is recommended that it is used in preference to the FFT in such situations The continuous Fourier technique has the additional advantage that it can be applied with greater confidence as the aliasing errors will not be present It does have its own source of error due to the fact that simulated data itself is not truly continuous but represented by unevenly spaced points with no information about what lies between the points This error can be minimised by ensuring that close simulation tolerances are used See the Convergence and Accuracy chapter of the Simulator Reference Manual for details Because each frequency component is calculated individually the calculation time is affected by the values entered in Frequency Display See below Plot Phase or Magnitude The default is to plot the magnitude of the Fourier spectrum Select Phase if you require a plot of phase or dB if you need the magnitude in dBs Frequency Display Resolution Hz Available only for the continuous Fourier
17. If checked the instance of the symbol owning the property can be selected by clicking in the property text It is recommended that this option is off unless the symbol has no body e g a pure text item If checked it will not be possible to edit or delete the property on a schematic instance of the symbol When this is not checked the size of the font is adjusted for best readability and does not necessarily scale exactly with the zoom magnification When the box is checked the font size follows the magnification in a linear fashion If selected the name of the property as well as its value will be displayed The value may contain expressions enclosed by and keywords enclosed by lt and gt and property names enclosed 99 User s Manual 100 by These items will each be substituted with their resolved value to obtain the property text that is actually displayed Expressions may contain the usual arithmetic operators and may also use functions as defined in the script reference manual Property names enclosed with are substituted with that property s value Keywords may be lt date gt lt time gt lt version gt lt if gt lt ifd gt and lt t gt lt date gt lt time gt resolve to date and time in local format and lt version gt resolves to an integer value which is incremented each time a schematic is saved The keywords lt if gt lt ifd gt and lt t gt behave in
18. Menu Cursors Hide Show Select allows you to selectively hide or show some cursors Freezing Cursors You can freeze the cursors so that they can t be moved accidentally Select menu Cursors Freeze Unfreeze Aligning Cursors Select menu Cursors Align to align the two cursors so that they have the same y position Changing Cursor Style The crosshair style is the default but there is an alternative style where each cursor is a small cross Select menu Cursors Set style to change This is the same style used with versions 3 1 and earlier Additional Cursors SIMetrix has the ability to display any number of cursors not just the standard two To Add an Additional Cursor Select menu Add Additional Cursor 2 Enter a suitable label for the cursor This is displayed at the bottom of the graph and to avoid clutter we recommend that you use a short label such as a single letter 3 Select to which other cursor you wish the new cursor to be referenced for both horizontal and vertical dimensions Select none if you do not wish it to be referenced to any currently displayed cursor Note that you may reference further additional cursors to this one if desired Chapter 9 Graphs Probes and Data Analysis 4 Press Ok The new cursor will be initially displayed at the start of the x axis and attached to the first curve on the sheet You may subsequently move it as desired To Remove Additional Cursors 1 Select
19. Overview The SIMetrix environment provides a facility to run automatic multiple SIMPLIS analyses Two modes are available namely parameter step and Monte Carlo In parameter step mode the run is repeated while setting a parameter value at each step The parameter may be used within any expression to describe a device or model value In Monte Carlo mode runs are simply repeated the specified number of times with random distribution functions enabled Distribution functions return unity in normal analysis modes but in Monte Carlo mode they return a random number according to a specified tolerance and distribution Any model or device parameter may be defined in terms of such functions allowing an analysis of manufacturing yields to be performed Comparison Between S IMetrix and SIMPLIS The multi step analysis modes offered in SIMetrix simulation mode achieve the same end result as the SIMPLIS multi step modes but their method of implementation is quite different SIMetrix multi step analyses are implemented within the simulator while the SIMPLIS multi step analyses are implemented by the front end using the scripting language The different approaches trade off speed with flexibility The approach used for SIMPLIS is more flexible while that used for SIMetrix is faster Setting up a SIMPLIS Multi step Parameter Analysis An Example We will begin with an example and will use one of the supplied example schematics First open the schemat
20. Single Ended Current In device pin Single Ended Current AC coupled in device pin Single Ended Current In wire Single Ended Current dB Single Ended Current Phase Single Ended Current Fourier Single Ended Current Nyquist Single Ended Current Normalised dB 219 User s Manual 220 Function Single Ended Current Group delay Differential Current Actual Differential Current dB Differential Current Phase Differential Current Fourier Differential Current Nyquist Differential Current Normalised dB Differential Current Group delay Power Impedance Output noise noise analysis only Input noise noise analysis only Device noise noise analysis only Arbitrary expressions and XY plots Notes on Probe Functions Impedance You may plot the AC impedance at a circuit node using Probe More Probe Functions This only works in AC analysis This works by calculating V I at the device pin selected Device Power Device power is available from Probe Power In Device This works by calculating the sum of VI products at each pin of the device Power is not stored during the simulation However once you have plotted the power in a device once the result is stored with the vector name device_name pwr E g if you plot the power in a resistor R3 its power vector will be called R3 pwr You can use this as part of an expression in any future plot Note that because SIMetrix is able to
21. micron advanced rtn or simplis_if Each feature must be checked in individually What Is Simetrix SIMetrix is a mixed signal circuit simulator designed for ease and speed of use It is based on two publicly available programs namely SPICE developed by the CAD IC group at the department of Electrical Engineering and Computer Sciences University of California at Berkeley and XSPICE developed by the Computer Science and Information Technology Laboratory Georgia Tech Research Institute Georgia Institute of Technology XSPICE itself was developed from SPICE3C1 Although originally derived from these programs only about 30 of the overall application code can be traced to them A large part of the simulator code is either new or has been rewritten in order to provide new analysis features and to resolve convergence problems In addition SIMetrix includes schematic entry and waveform analysis features that owe nothing to the original SPICE program Features Closely coupled direct matrix analog and event driven digital simulator Fully integrated hierarchical schematic editor simulator and graphical post processor Superior convergence for both DC and transient analyses Pseudo transient analysis algorithm solves difficult operating points while enhanced transient analysis algorithm virtually eliminates transient analysis failures g Advanced swept analyses for AC DC Noise and transfer function 6 different modes available
22. or if the models were installed more than 30 days ago select All User Models You should see the models you have installed listed on the right hand side Select the device you wish to place the press Place At this point one of two things will happen Either A schematic symbol will appear possibly after a short delay for you to place on the schematic sheet If so no further action is needed after placing the symbol OR If SIMetrix is unable to identify a suitable schematic symbol for the model the associate models and symbols dialog box will open See next step The following dialog box will be displayed a Associate Symbol with Model SXOA1000 STEP 1 Select a suitable category for this part Choose Category for SX0A1000 If you can t find one press New Category Unassigned New Category and enter a new category of your choice e STEP 2 Select a suitable symbol for this part Define Symbol for SXOA1000 Select a symbol from the drop down box or press Auto Create Symbol to create a new one AD567 Auto Create Symbol If selecting an existing symbol you must make Pin order 4 ED ae sure that the pin order matches the model ieee as definition shown below Press Help for I et assistance E If you use Auto Create Symbol the pin order L FA a nae will not need to be changed Electrical Model SXOA1000 From C Program Files sIMetrix53 examples Tutorial3
23. will output to data txt the vectors vout rl_p and qli c The values will be output in a form compatible OpenGroup text Vector Names In the above example the vector names are vout rl_p and ql c If you simulate a schematic the names used for voltage signals are the same as the node names in the netlist which in turn are assigned by the schematic s netlist generator To find out what these names are place the mouse cursor on the node of interest on the schematic then press control S The node name and therefore the vector name will be displayed in the command shell A similar procedure can be used for currents Place the mouse cursor on the device pin of interest and press control P Launching Other Applications Data import and export makes it possible to process simulation data using other applications SIMetrix has a facility to launch other programs using the Shell command You could therefore write a script to export data process it with your own program then read the processed data back in for plotting To do this you must specify the wait switch for the Shell command to force SIMetrix to wait until the external application has finished E g Shell wait procdata exe will launch the program procdata exe and will not return until procdata exe has closed Chapter 9 Graphs Probes and Data Analysis Data Files Text Format SIMetrix has the ability to read in data in text form using the OpenGroup command page 294 This ma
24. Both the examples shown in Sweep Modes on page 176 are AC analyses The following is a frequency sweep which is the traditional AC analysis mode This was performed on the circuit shown on page 178 with restail 1k i Frequency sweep of diff amp circuit 4 2 gt zo 5 400m 200m 10k 100k 1M 10M 100M 1G Frequency Hertz Noise Analysis Like AC analysis AC Noise analysis is a small signal mode The circuit is treated as linear about it s DC operating point and the contribution of all noisy devices to a designated output is computed The total noise at that output is also calculated and optionally the noise referred back to an input source may also be computed Like DC AC and Transfer Function it is a swept mode and can be operated in any of the 6 modes described in Sweep Modes on page 176 With some of these modes e g sweeping a resistor value it will be necessary for the DC operating point to be recalculated at each point while with others such as frequency sweep it is only necessary to calculate it at the start of the run Note that it is not necessary to apply an AC specification to any source including the optional input referred source as it is with standard SPICE and many if not all of its derivatives Setting up an AC Noise analysis 1 Select menu Simulator Choose Analysis 2 Select Noise check box on the right 183 User s Manual 184 3 Select Noi
25. ButterworthHP order cut off Butterworth high pass ChebyshevLP order cut off Chebyshev low pass passband_ripple ChebyshevHP order cut off Chebyshev high pass passband_ripple Where order Integer specifying order of filter There is no maximum limit but in practice orders larger than about 50 tend to give accuracy problems cut off 3dB Frequency in Hertz passband_ripple Chebyshev only Passband ripple spec in dB Arbitrary Non linear Passive Devices Each of these will place a component which looks exactly like its linear counterpart The difference is that when you try and edit its value with F7 or menu Edit Part you will be prompted to enter an expression In the case of the resistor and capacitor this Chapter 5 Components relates its value to the applied voltage and for inductor the expression relates its inductance to its current For resistors and capacitors the terminal voltage is referred in the equation as V N1 and for inductors the device s current is referred to as I V1 Creating Models Overview SIMetrix version 5 1 introduced a new soft recovery diode model for use in power electronics circuits As this model is not a SPICE standard there are no models available from device manufacturers or other sources So we therefore also developed a soft recovery diode parameter extractor that allows the creation of soft recovery diode models from data sheet values The parameter extraction
26. DefMenu Composed of strings separated by pipe symbol First name must be one of the following SHELL Command shell menu SCHEM Schematic popup menu SIMETRIX Schematic popup menu S Metrix mode only SIMPLIS schematic popup menu SIMPLIS mode only GRAPH Graph popup menu GRAPHMAIN Graph fixed menu SCHEMMAIN Schematic main menu SIMETRIXMAIN Schematic main menu SIMetrix mode only SIMPLISMAIN Schematic main menu SIMPLIS mode only SYMBOL Symbol editor popup menu SYMBOLMAIN Symbol editor fixed menu This must be followed by at least two separated values for main menus and at least one separated value for popup menus Each name describes one level in the menu hierarchy Use the amp symbol to define an underlined ALT key access letter To define a menu separator use the item text Note that if a menu name contains spaces it must be enclosed in quotation marks A boolean expression specifying under what circumstances the menu should be enabled The menu text turns grey when disabled If omitted the menu will always be enabled For details see DefMenu description in the Script Reference Manual 293 User s Manual 294 Notes Changes to a schematic or symbol editor main menu will not affect currently open windows For the changes to take effect close the schematic symbol editor window and open a new one DelMenu DelMenu bypos position menuname Deletes specified menu positi
27. Digital only Wildcard filter Use to match one or more characters Use to match a single character This allows you to select what is displayed in the available vectors dialog This is useful when simulating large circuits and the number of vectors is very large Sub circuit Filter All Vectors at all levels are displayed Top level Only vectors for the top level are displayed Select sub circuit All sub circuit references will be displayed in the list box Select one of these Only vectors local to that sub circuit will be displayed in Available Vector list Signal Type All List all signal types Voltages Only Only voltages will be listed Currents Only Only currents will be listed Digital Only Only digital vectors will be listed Wildcard filter Enter a character string containing and or to filter vector names matches 1 or more occurrences of any character and matches any single character Some examples X matches anything X1 matches any signal name that starts with the three letters X1 X matches any name that starts with an X and with a for the third letter 230 q10 c Ul vout Curve Label Chapter 9 Graphs Probes and Data Analysis matches any name ending with q10 c i e the current into any transistor called q10 matches any name ending with U1 C11 i e any node called vout in a subcircuit with reference U1 Enter text string to label curve Ax
28. Edit Add Free Text respectively Note you can use the enter key to add a new line The actual fonts used can be changed with File Options Font Note the fonts are global and not stored with the schematic Assigning Component References Standard Behaviour As you place components on a schematic they are automatically assigned a component reference R1 Q42 C11 etc These references are assigned in sequence and breaks in the sequence are reused So if you place resistors on the schematic R1 R2 R3 and R4 then delete R2 the next resistor placed will use the reference R2 that has become available Setting Start Value By default auto assigned references start at 1 You can change this using the AnnoMinSuffix option variable see page 332 For example type this at the command line Set AnnoMinSuffix 100 Auto assigned component references will now begin with 100 Chapter 4 Schematic Editor Assigning By Position You can reassign component references so that they are allocated by their position on the schematic To do this select menu Edit Assign References By Position Checking the Schematic The schematic menu Simulator Check performs a number of checks First a netlist of the circuit is created During this process the following potential errors will be reported E Unconnected pins Dangling wires 3 Implicit connections e g two terminal symbols with the same name Name translations This is for b
29. In the specialised method a special script is called which edits one or more properties of the schematic instance With a capacitor for example the VALUE property is edited so that the IC parameter is specified or modified Something similar is done for Chapter 8 SIMPLIS Analysis Modes inductors This action is done using a special script specified by the INIT SCRIPT property In the case of the capacitor the script ic_reactive is called The advantage of the specialised method is that the device can be modified in a manner that is consistent with its existing user interface Capacitors already have user editable initial conditions and the application of back annotated initial conditions is compatible with this The disadvantage of the specialised method is that a method of applying the back annotated value needs to be developed for every different type of device This would not be acceptable for most users who develop their own symbols The generic method overcomes this difficulty The generic method modifies the properties so that additional netlist lines are created containing the INIT simulator command that defines the initial conditions To achieve this the SIMPLIS_TEMPLATE property needs to be modified and as long as this isn t protected the generic method will always work Hierarchical Blocks and Subcircuits All back annotated initial conditions are applied at the top level and no child schematics or subcircuits will be mod
30. In this case the trace will always have the same colour Chapter 9 Graphs Probes and Data Analysis Plot on completion only If checked the curve will not be created until the analysis is finished Otherwise they will be updated at an interval specified in the Options dialog File Options General see Options on page 325 Axis Scales Sheet PS Edit Probe K Probe Options Axis Scales Axis Labels Xs YAris O Ln O Lo O Lin O Log Auto No change No change O Auto scale Auto scale Defined Defined X Axis Y Axis X and Y axis parameters Lin Log Auto Specify whether you want X Axis to be linear or logarithmic If Auto is selected the axis X or Y will be set to log if the x values are logarithmically spaced For the Y axis it is also necessary that the curve values are positive for a log axis to be selected No Change Keep axis scales how they are Only relevant if adding to an existing graph Defined Set axis to scales defined in Min and Max boxes Axis Labels Sheet This sheet has four edit boxes allowing you to specify x and y axis labels as well as their units If any box is left blank a default value will be used or will remain unchanged if the axis already has a defined label Fixed Bus Probe Options Select device and press F7 in the usual manner For details about bus probe options please see Bus Probe Options on page 227 217 User s Manual Using Fixed
31. Probe update times Plots created from fixed probes are updated on a regular basis This controls how frequently and when it starts Period Update period in seconds Start Start delay in seconds Temporary data file delete Simulation data is stored in data files that are placed in the temporary data directory see file locations below These options control when these data files are deleted 327 User s Manual 328 Sizes Cursor readout Histogram style Never Temporary files are never deleted but will be overwritten in subsequent sessions Not recommended unless you only ever do short simulations When SIMetrix starts All temporary files are deleted when SIMetrix starts When SIMetrix closes All temporary files are deleted when SIMetrix is shut down While using SIMetrix you can recover earlier simulation runs Normally only the 3 most recent are kept but earlier ones can be recovered from the TEMPDATA directory using File Load Data When data is no longer needed This is the most aggressive delete method and is recommended if you do many long runs or and have limited disc space By default the 3 most recent runs are kept but with the other options above the data files are not deleted when the data is not needed but links to the data in them are released See explanation below If this option is set the data files are deleted as soon as they become out of date optimising use of disc space at the ex
32. Real time noise analysis allowing noise simulation of oscillators and sampled data systems s Support for BSIM3 BSIM4 and MOS9 devices Compatible with Star Hspice model files 27 User s Manual Cross probing of voltage current and device power from schematic Current and power available for sub circuits Monte Carlo analysis including comprehensive tolerance specification features Full featured scripting language allowing customised waveform analysis and automated simulation d Incremental plotting of results as simulation proceeds Functional modelling with arbitrary non linear source and arbitrary linear s domain transfer function Arbitrary logic block for definition of any digital device using descriptive language Supports synchronous asynchronous and combinational logic as well as ROMS and RAMs 7 Models for saturable magnetic components including support for air gaps User definable fixed and popup menus and key definitions What is SIMPLIS 28 SIMPLIS is a circuit simulator designed for rapid modelling of switching power systems An acronym for SIMulation for Piecewise LInear System it is supplied with the premium version of SIMetrix namely SIMetrix SIMPLIS SIMPLIS is a component level simulator like SPICE but is typically 10 to 50 times faster when simulating switching circuits It achieves its speed by modelling devices using a series of straight line segments rather than solving n
33. UpdateClosedSchematics 233 OUT CAT 164 Overshoot calculating 250 252 function 274 P parallel template property keyword 112 Parameters 154 list file output 194 passing through hierarchy 85 passing through subcircuits 152 start up 323 sweeping 177 with multi step analysis 196 params property 105 Parts browser 157 PassUnresTemplate option variable 339 Path names symbolic 321 Peak calculating 248 Peak Peak calculating 248 PeakToPeak function 275 Period function 275 Periodic operating point 203 205 ph function 309 Phase function 309 plotting 68 214 219 phase_rad function 309 pinlist template property keyword 109 pinnames template property keyword 109 Pins global 84 Plotting 361 User s Manual arbitrary expressions 228 noise analysis 221 results from earlier run 239 see also Probing transfer function analysis 221 X Y 229 Pole zero analysis 191 viewing results 191 POP 203 205 Potentiometer 138 Precision option variable 339 PrintOptions option variable 339 PrintWireWidth option variable 339 ProbeStartDelay option variable 339 ProbeUpdatePeriod option variable 339 Probing 66 69 212 213 234 arbitrary expressions 69 228 busses 226 device power 220 fixed 66 214 218 after run has started 218 changing update delay and period 218 327 current 67 differential voltage 67 69 in hierarchy 218 list of types 214 options 215 persistence 215 voltage 67 fixed vs random 213 fourier phase 224 fourie
34. may only take a single curve As their name suggests they are intended for digital traces but can be used for analog signals if required Check the Use Separate Graph box if you wish a new graph sheet to be used for the probe You may also supply a graph name This works in the same way as axis name see above It is not a label but a means of identification Any other probes using the same graph name will have their curves directed to the same graph sheet Specifies for which analyses the probe is enabled Note other analysis modes such as noise and transfer function are not included because these don t support schematic cross probing of current or voltage If the schematic is in SIMPLIS mode SIMetrix SIMPLIS product only the analysis POP will show instead of DC Sweep Display order digital curves Colour Enter a string to control display order for digital curves Normally digital curves are ordered according to their title The value supplied here will be used instead if not empty To force the curve to be placed above other curves that don t use this value prefix the name with The character has a low ASCII value Conversely use to force curve to be displayed after other curves If Use default is checked the colour will be chosen automatically in a manner that tries to minimise duplicate colours on the same graph Alternatively uncheck this box then press Edit to select a colour of your choice
35. number of points further Usually an interpolation order of 2 is a suitable value but you should reduce this to 1 if analysing signals with abrupt edges If analysing a smooth signal such as a sinusoid useful improvements can be gained by increasing the order to 3 Advanced Options Pressing the Advanced Options button will open this dialog box 225 User s Manual 226 E Advanced Fourier Data span Window Ou i Rectangular O Specify Hanning Start 0 Hamming End 5u Blackman Data Span Usually the entire simulated time span is used for the fourier analysis To specify a smaller time interval click Specify and enter the start and end times Note that if you specify a fundamental frequency the time may be modified so that a whole number of cycles is used This will occur whether or not you explicitly specify an interval Window A window function is applied to the time domain signal to minimise spectral leakage See above The choice of window is a compromise The trade off is between the bandwidth of the main spectral component or lobe and the amplitude of the side lobes The rectangular window which is in effect no window has the narrowest main lobe but substantial side lobes The Blackman window has the widest main lobe and the smallest side lobes Hanning and Hamming are something in between and have similar main lobe widths but the side lobes differ in the way they fall aw
36. specified then the group will be named Chapter 11 Command and Function Reference textn where n is chosen to make the name unique ReadLogicCompatibility ReadLogicCompatibility filename Reads a file to define the compatibility relationship between logic families For an example of a compatibility table see the file COMPAT TXT which you will find in the SCRIPT directory This file is actually identical to the built in definitions except for the UNIV family which cannot be redefined Please refer to the Digital Simulation chapter of the Simulator Reference Manual for full details on logic compatibility tables File Format The file format consists of the following sections Header In Out resolution table In In resolution table Out Out resolution table Header The names of all the logic families listed in one line The names must not use the underscore _ character In Out resolution table A table with the number of rows and columns equal to the number of logic families listed in the header The columns represent outputs and the rows inputs The entry in the table specifies the compatibility between the output and the input when connected to each other The entry may be one of three values Fully compatible Not compatible but would usually function Warn user but allow simulation to continue Not compatible and would never function Abort simulation In In resolution table A table with the number o
37. 1 al Detine core Units Ae hoo aj O Select core type ETRE mm Manual entry O cm ig 10 3 inches Core material 3C81 v O metres Ue 1k 3 Primary inductance 125 664mH ee Saturation current 35 8099m4 2 Specify the number of windings required for primary and secondary in the Configuration section If you just want a single inductor set primary turns to and secondaries to 0 3 Specify turns ratios in the Define Windings section You can select the winding to define using the Select Winding drop down box then enter the required ratio to primary 1 in the edit box below it 4 Specify the number of turns for the primary and coupling factor The coupling factor is the same for all windings You can define different coupling factors for each winding by adding ideal inductors in series with one or more windings In some instances it may be necessary to add coupled inductors in series This is explained in more detail in Coupling Factor on page 136 5 Specify the core characteristics in the Define Core section A number of standard core sets are pre programmed and can be selected from the Select Core Type list at the top If the part you wish to use is not in the list or if you wish to use a variant with a say different air gap you can manually enter the characteristics by clicking on the Manual Entry check box The values you need to enter are Effective Area Effective Length Relative Permeabili
38. 13 Sundry Topics Allow route through connected is an option for the smart wiring algorithm that allows it select routes that pass through existing wires that are already connected to the source or target destinations Classic Double click action behaves the same as for versions 4 5 and earlier Edit selected component Double clicking a symbol in the schematic invokes the value editor Same as pressing F7 Controls how wires are treated during move operations See Edit Modes on page 76 for full details Width in mm of printed axis Width in mm of printed grid lines Width in mm of printed curves When printing on monochrome printers or if Use markers for colour is selected curves are differentiated using different line styles solid dashed etc and marker shapes circles squares etc For a large number of curves both methods are used but for just a few you can use this option to state your preference Prefer line styles printed curves will first be differentiated using line styles Prefer curve markers Printed curves will first be differentiated using curve markers Use markers for colour Even if printing to a colour printer curves will still be printed using markers and variable line styles to differentiate them They will also be printed in colour This is useful when creating on line documents e g using Adobe Acrobat Distiller which might subsequently be viewed on line or printed out Graph Probe Data Analysis
39. 3644V Current and Voltage plotted on separate Axes PSU Waveforms Selected Jes File Edit Cursors Annotate Curves Axes View Measure Plot PRAA DH ER EER SURE Re m IL3 P m 51 P trant I L3 P KL3 P sA SsiPiv 1 98 2 2 02 2 04 2 06 2 08 24 TimekSecs 20Secsidiv x 1 95767k5ecs y 15 064 Current and Voltage plotted on separate Grids 236 Chapter 9 Graphs Probes and Data Analysis AutoAxis Feature When you plot a new curve on an existing graph SIMetrix will select or if necessary create a compatible axis for that curve The decision is made on the basis of the curve s Units i e voltage current etc The rules it follows are 1 Ifthe currently selected axis or grid shown by black axis line has the same units as curve to be plotted or if it has undefined units designated by a on label that axis will be used 2 Ifany other axis or grid has compatible units i e same as curve or undefined that axis will be used 3 Ifno axes exist with compatible units a new axis not grid will be created to accommodate the curve The above works for all plots made using random probes For plots created with fixed probes the above is the default behaviour but this can be changed See Fixed Probes on page 214 for more details For plots created using the Curve command at the command line the AutoA
40. 74 copying across schematics 73 deleting wires 72 disconnecting wires 54 72 duplicating items 72 labelling nets 80 move single component 72 moving labels 72 74 placing components 71 rotate mirror or flip a component 54 71 undo 73 undo setting level 326 wiring 72 getting started 53 grid hiding 326 hierarchical 80 ascending 82 bottom up method 81 connecting busses 83 creating blocks 80 descending 82 global nets 84 global pins 84 navigating 81 passing parameters 85 probing 218 233 running simulation 65 364 top down method 80 importing models 165 modes 70 net names displaying 80 user defined 80 preferences 79 component placement options 79 toolbar 79 properties 90 102 decscript 105 editing in schematic 106 handle 105 incscript 105 lot 105 mapping 105 match 105 model 104 151 netname 105 params 105 ref 104 151 restoring 106 schematic_path 105 scterm 105 simulator 105 template 105 tol 105 value 104 151 valuescript 105 selecting 71 components only 73 multiple 73 wires only 73 symbols adding properties 97 changing search order 116 copying 116 creating 94 creating from script 102 defining pins 95 drawing arcs 94 drawing segments 94 editing 94 editing properties 100 Index 365 User s Manual graphical editor 93 how they are stored 121 installing 115 library manager 114 pin order 96 properties 90 102 renaming 116 symbol generator 88 uninstalling
41. A i j 2 o 5 TimekSecs 20Secsidiv x 2 07761kSecs y 16 36444 Note that the legend panel can be resized With most systems a resize handle is clearly visible on the lower edge but with the standard Windows XP theme e g the above picture this is not the case Windows and Tabbed Sheets Normally new graphs are created within the same window as a tabbed sheet A row of tabs will appear at the top of the graph window allowing you select which graph you wish to view You can also create a new graph window using the menu Probe New Graph Window This will create an empty window to which you may add new graphs 212 Chapter 9 Graphs Probes and Data Analysis Graph Toolbar Display 3dB High Pass Display 3dB Low Pass Move curve to Display Average Cycle new axis grid Display RMS Cycle Name Gunes Display Fall Time Hide selected curves Display Rise Time Show Selected Curves PRIA ADRE E E E AUTER Undo Graph T Create New a Fit Height Create New Axis Fit Widt Erase Axis Fit Page Graph toolbar The above shows the function of each of the buttons on the graph toolbar These are referred to in the following sections Probes Fixed vs Random Much of this section and some of the next have already been covered in Plotting Simulation Results on page 66 It is repeated here for convenience SIMetrix provides two approaches to creating plots of simulated results
42. A aes irf540ns IRF610S IRF640S a t Pe n mi gt C Program Files SIMetrix53 support models masfet Ib Select the appropriate category on the left then the part number on the right If you are not sure what category the component is in select the All Devices category which you will find at the bottom of the category list If you are looking for a part that you installed as opposed to a part supplied with SIMetrix then you will find it in the All User Models category as well as the All Devices category If installed within the last 30 days you will also find it under Recently Added Models To reduce the number of devices displayed to a manageable level you can specify a filter You can use the wild cards and here will match 1 or more of any character while will match any single character So on its own will match any string and so all devices will be displayed But IRF will display any device that starts with the three letters IRF IRF will display any device beginning with IRF and followed by three and only three characters Numbered Components in SIMPLIS This section applies only to the SIMetrix SIMPLIS product SIMPLIS works in a quite different way to SIMetrix SPICE and as a result its models for semiconductor devices are completely different For that reason the selection of 126 Chapter 5 Components devices available from Place From Mo
43. Associating Multiple Models with Symbols on page 161 Passing Parameters You can pass parameters to a subcircuit This subject is covered in detail in the Simulator Reference Manual To specify the parameters for a sub circuit device in a schematic you must enter the values manually using shift F7 and placing a between the sub circuit name and the parameter list E g suppose you wished to specify the parameters FREQ 12k Q 15 To enter these select the sub circuit press shift F7 and append the sub circuit name with FREQ 12k Q 15 Note for information about passing parameters to a hierarchical block please refer to Passing Parameters Through a Hierarchy on page 85 Chapter 5 Components Special Components Initial Conditions Initial conditions force a node to a fixed voltage or current during the calculation of the DC bias point There are two types of initial condition namely soft and hard Soft initial conditions apply a voltage through a fixed resistance Hard initial conditions apply a voltage directly without any resistance To Place a Soft Initial Condition 1 Select menu Place Connectors Initial Condition 2 Place device at the desired location then select and press F7 Enter a suitable voltage To Place a Hard Initial Condition 1 Select menu Place From Symbol Library 2 Select device Connections Ics and Nodesets Initial Condition Hard 3 Place device at the desired location then select an
44. Cursors Remove Additional Cursors 2 Select the cursor or cursors to be removed These are identified by their labels Cursor Readout There are a number of options as to how the cursors absolute and relative positions are displayed Initially all values are displayed as dimensions on the graph This can be altered in a number of ways You can opt to have just the absolute or just relative readings displayed E The actual format of the graph readout can be customised E g extra text can be added perhaps something like Delay xxxnS where xxx is the relative reading The values can optionally be displayed in the status bar with or without the graph readings Editing Style or and Format of Cursor Dimension Double click on one of the displayed values of the cursor dimension The following dialog will open A Edit Crosshair Dimension B Properties Edt Label Style Label 1 x1 Show Absolute Show Difference Label 2 x2 Automatic Internal Label 3 xdlitt Eztemal Font Items enclosed with are symbolic Edit Font values See help for details Edit values as described below Label The labels are the three values displayed on the dimension Label 1 is the value displayed above the reference cursor label 2 is the value displayed above the main cursor and label 3 is the value displayed as the difference x1 x2 and xdiff are symbolic values that will be substituted with t
45. Data Group menu item Although only three groups are held at a time the data is actually stored on a disc file which will not necessarily have been deleted If you wish to access an old run use File Load Data and retrieve the data from the TEMPDATA directory created under the SIMetrix install directory The file will have the same name as the group appended with SXDAT In the case of monte carlo analyses it will be named MCn SXDAT Whether or not the data file is still available depends on a preference setting See Graph Probe Data Analysis on page 327 for details Combining Results from Different Runs There are occasions when you wish to say plot the difference between a node voltage for different runs To do this in SIMetrix you need to type a command at the command line This will be of the form Plot vector1 vector2 for the example of plotting the difference vector and vector2 are the names of the signals However as the two signals come from different runs we need a method of identifying the run This is done by prefixing the name with the group name followed by a colon The group name is an analysis type name tran ac op dc noise tf or sens followed by a number The signal name can be obtained from the schematic For voltages put the cursor over the node and press control S For currents put the cursor on a device pin and press control P The group name is displayed in the simulator progress box when the simula
46. GraphMainButtons Graph window toolbar 345 User s Manual Startup Auto Configuration 346 Overview When SIMetrix is started for the first time it automatically sets up its configuration to default values Details of this process are provided in the following sections There are a number of settings that can be made to control this process and these are also explained What is Set Up During this phase the following is set up Installs system supplied symbol libraries Installs system supplied model libraries Migrates preference settings from earlier installed versions if available Associates file extensions with the operating system Windows only Gv ae IN a Sets up default window positions according to the system screen resolution only if preference settings not migrated in 3 6 Define default values for various fonts only if preference settings not migrated in 3 Auto Configuration Options Configuration settings are stored in a file called base sxprj See Configuration Settings on page 324 for details of where this file is located Auto configuration writes values to this file but will also read values from this file to decide how it will proceed In the usual sequence of events for installing and setting up SIMetrix this file will not actually exist when auto configuration occurs In this case auto configuration uses default values for the settings it tries to read However if you are a system administ
47. Now enter a after this then click on the pin of the E1 This is what should be in the box R4_N R3_N 5 Close box You should see something like this 267 User s Manual 268 Mean 2 85301 Std Dev 30 3897m Frequency counts 2 78 2 8 2 82 2 84 2 86 2 88 2 9 2 92 Voltage V 20mV div This is a histogram showing the distribution of the gain of the amplifier at 100kHz Goal Functions A range of functions are available to process curve data Some of these are primitive and others use the user defined function mechanism Primitive functions are compiled into the binary executable file while user defined functions are defined as scripts and are installed at functions at start up User defined functions can be modified and you may also define your own For more information refer to the Script Reference Manual This is available as a PDF file on the install CD A hardcopy version is also available for an additional charge The functions described here aren t the only functions that may be used in the expression for performance analysis They are simply the ones that can convert the array data that the simulator generates into a single value with some useful meaning There are many other functions that process simulation vectors to produce another vector for example log sqrt sin cos and many more These are defined in Function Reference on page 301 Of particular interest is the Tr
48. Place From Model Library and select your desired device Once the symbol has been selected using the mouse move the image of the component to your desired location then press the left mouse button This will fix the component to the schematic Depending on preference settings command shell menu File Options General schematic tab you may now be presented with another copy of the symbol for placement Use left key as before to place press right key to cancel Selecting a Single Component Most operations require items to be selected When an item component or wire is selected it changes colour to blue To select a single component just left click it Selecting an Area To select all items within a rectangular area of the schematic press the left mouse key in an empty area of the sheet and hold down while dragging mouse to opposite corner of rectangle A rectangular box should be drawn as you move the mouse Note that if the initial cursor position is too close to a wire junction or component a move operation will be carried out instead of selection To Change Value or Device Type for a Component First select it then select schematic popup Edit Part or press F7 Alternatively you can just double click the device Note that the double click behaviour is new for version 5 1 and may be disabled for backward compatibility See Using the Options Dialog on page 326 for details A dialog box appropriate for the type of com
49. Probes in Hierarchical Designs Fixed probes may successfully be used in hierarchical designs If placed in a child schematic a plot will be produced for all instances of that child and the labels for each curve will be prefixed with the child reference Adding Fixed Probes After a Run has Started When you add a fixed probe after a run has started the graph of the probed point opens soon after resuming the simulation This doesn t apply to differential voltage probes To do this 1 Pause simulation 2 Place a probe on the circuit in the normal way 3 Resume simulation Changing Update Period and Start Delay The update period of all fixed probes can be changed from the Options dialog box Select command shell menu File Options General and click on the Graph Probe Data analysis tab In the Probe update times seconds box there are two values that can be edited Period is the update period and Start is the delay after the simulation begins before the curves are first created Random Probes 218 General Behaviour A wide range of functions are available from the schematic Probe and Probe AC Noise menus With a few exceptions detailed below all random probe functions have the following behaviour If there are no graph windows open one will be created If a graph window is open and the currently displayed sheet has a compatible x axis to what you are probing the new curve will be added to that sheet E g if the curr
50. Rotated Justification Hidden Vertical Chapter 4 Schematic Editor automatically outside the symbol s border according to the options specified in Normal and Rotated When absolute is selected the property is placed at a fixed position relative to the symbol body You can define the location interactively with the mouse When auto is selected the text is always horizontal when absolute is selected the text is vertical when the symbol is at a 90 degree rotation When auto is selected this specifies which side of the symbol the text is located when the symbol is in normal orientation When auto is selected this specifies which side of the symbol the text is located when the symbol is rotated 90 degrees Defines the reference point on the text when absolute is specified See diagram below for meaning of options The reference point is always at a fixed location with respect to the symbol body The position of the remainder of the text may vary with zoom level or font size Centre Property Text The property s value text will not be displayed in the schematic Top Base line If checked the property will be displayed vertically This option is only available if absolute location is selected Property Attributes Font style Selectable Protected Linear Show Name Resolve symbolic Select one of eight font styles The actual font definition is defined by the Font dialog box See page 348 for details
51. SIMetrix or SIMetrix SIMPLIS license In cases where the license file is not automatically installed such as on Linux systems you will be prompted to find a license file with a dialog similar to the following Chapter 1 Introduction License File Required standalone License Details 4 license file is required to run this version of SlMetrix Push this button if you already have a license file If you have not yet obtained a license file please email support catena uk com providing the following information Host ID MACO00c296bfe51 Purchasing information PO Number date of purchase reseller if applicable This information has been copied to the system clipboard Close The above screen captured image was taken from a SusE Linux system The layout will be similar for Windows and other Linux distributions although the style may be quite different If you have already received a license file perhaps by Email then simply press Install License and locate the license file on your machine SIMetrix will copy this file to the correct location On Linux stand alone systems you will normally find the license file on the install CD at mnt cdrom license If you do not yet have a license file please email support catena uk com providing the Host ID and Serial Number information supplied Standalone Licensing for Remote X Servers Linux only Standalone SIMetrix licenses cannot be used on a remote
52. Select the menu File Open Schematic Select the schematic file TUTORIAL which you should find in the folder EXAMPLES TUTORIALS See Examples and Tutorials Where are They on page 32 Select Open to open this file A schematic window will open with the following circuit This is a simple feedback amplifier designed to amplify a 100mV pulse up to around 500mV The basic requirement of the design is that the pulse shape should be preserved DC precision is important but is not critical The above is our first 33 User s Manual 34 attempt at a design but has not yet been optimised This example circuit has been setup to be ready to run 2 To start the simulation select from the schematic window Simulator Run or press F9 The simulation will not take long on a modern machine less than half a second You will see a graph of the output voltage appear 60 501 40 301 Amplifier Output mV 201 0 2 4 6 8 10 Time uSecs 2uSecs div As can be seen our amplifier doesn t work all that well There are two problems 1 There is substantial ringing on the rising edge probably caused by the capacitative load 2 The falling edge is somewhat sluggish The sluggish falling edge is caused by the absence of any standing current in the output emitter follower Q3 To rectify this we will place a resistor from the emitter to the 5V rail The resulting s
53. Temporary Data Whether or not there will be any files available to opened depends on the temporary data file delete options See Graph Probe Data Analysis on page 327 for information about these options The error The process cannot access the file because it is being used by another process means that the temporary data file is still in use Unless the file is in use by another instance of SIMetrix you will be able to use its data by selecting its associated group Use menu Graphs and Data Analysis Change Data Group Chapter 9 Graphs Probes and Data Analysis Performance Analysis and Histograms Overview When running multi step analyses which generate multiple curves it is often useful to be able to plot some characteristic of each curve against the stepped value For example suppose you wished to investigate the load response of a power supply circuit and wanted to plot the fall in output voltage vs transient current load To do this you would set up a transient analysis to repeat a number of times with a varying load current See Multi step Analyses on page 194 to learn how to do this After the run is complete you can plot a complete set of curves take cursor measurements and manually produce a plot of voltage drop vs load current This is of course is quite a time consuming and error prone activity Fortunately SIMetrix has a means of automating this procedure A range of functions sometimes known as goal f
54. The analysis definition must specify the component reference for the device The following types of device may be used Device Value swept Capacitor Capacitance Diode Area Voltage controlled voltage Gain source Current controlled current Gain source Voltage controlled current Transconductance source Chapter 7 Analysis Modes Device Value swept Current controlled voltage Transresistance source Current source Current JFET Area Inductor Inductance Bipolar Transistor Area Resistor Resistance Lossless Transmission Line Impedance Voltage source Voltage GaAs FET Area Temperature Global circuit temperature is swept Model Parameter Similar to device sweep except applied to a named model parameter Both the model name and the parameter name must be specified Special Note It is recommended that any model parameter being swept is also specified in the MODEL parameter list In most cases it isn t actually necessary but there are a few instances such as for terminal resistance parameters where it is necessary Parameter A user named variable that can be referenced in any number of expressions used to define model or device parameters Here is an example See Examples Sweep AC_Param sxsch 177 User s Manual 5V Gy AC 10 restail R1 5v S U SUB This is a simple long tailed pair The above circuit resistors R1 and R2 have been given the values restail res
55. User s Manual The contents of usr lib simetrix v5 3 may not be relocated If disk space on the partition holding usr local is scarce then you can move the directory and drop a symbolic link in its place Do not under any circumstances be tempted to move the contents of asr lib simetrix v5 3 to a global library directory such as usr lib SIMetrix will probably work fine but other applications could break in particular the KDE desktop environment Uninstalling Linux Version There is no uninstall program supplied with Linux versions To remove simply delete the folder where you installed it This is usually usr local simetrix_xx where xx is the version Files are also installed to usr local lib simetrix x x where x x is the version You should only remove these files if you are removing all versions of SIMetrix on your system In addition to the standard program files SIMetrix puts some files in HOME simetrix These can be removed if you are removing all versions of SIMetrix from your system Licensing 18 Overview Essentially there are two classes of license namely stand alone licenses controlled by a single license file and network licenses controlled by a license server Installing Stand Alone License Files Stand alone license files are usually pre burned on the SIMetrix CD and on Windows systems are automatically installed during the setup process If this is the case no action needs to be taken to setup a
56. User Name Enter the name as you wish it to be displayed in the dialog box opened with the schematic menu Parts All Symbols Define Symbol Internal Name For a new symbol an internal name will automatically be entered when you type the User Name In most cases you can leave it at that However the internal name must be unique across the whole model library so there may be situations where you will need to change it Define Symbol Category Enter a category to determine how the symbol will be listed in the dialog box opened with the schematic menu Place From Symbol Library Sub categories are separated using a semi colon Note that you can easily move symbols to different categories using the symbol library manager So if you are unsure at this stage what category to use you can place it in a temporary category and move it later Define Symbol All references to symbol automatically updated If this is checked any changes you make to a symbol will automatically be applied to any instance of it in existing schematics whether they are open or not If it is not checked instances of the symbol will not be updated until the Update Symbols menu is selected in the schematic Copies of all symbols used by a schematic are stored locally within the schematic and that local version will only be updated if this box is checked See How Symbols are Stored on page 121 for further details 101 User s Manual Save to Libra
57. Write bias info and save state Performs both operations described in 1 and 2 above Creating Snapshots on Demand You can create a snapshot of a transient run after it has started by executing the SaveSnapShot script command Proceed as follows 1 Pause the current transient analysis or allow it to finish normally You must not abort the run as this destroys all internal simulation data Type at the command line the edit box below the menu bar in the command shell window SaveSnapShot That is all that is needed You can now start a new small signal analysis using the snapshot created Applying Snapshots to a Small Signal Analysis Poe e Select menu Simulator Choose Analysis Select AC TF or Noise analysis Press Define Multi step Analysis for the required analysis mode Select Snapshot mode The analysis will be repeated for all available snapshots Chapter 7 Analysis Modes Important Note Snapshot data can only be applied to an identical circuit to the one that created the snapshot data So you must make sure that any components needed for a small signal analysis that uses snapshot data are already present in the circuit before the transient run starts In particular of course you must make sure that an AC source is present An error message will be output if there are any topological differences between the circuit that generated the snapshot data and the circuit that uses it If there are only component or
58. a module port use schematic menu Hierarchy Place Module Port 2 Save the schematic as a component Select menu Save As then select Components from Save as type list Creating Symbol for Schematic 1 Select Hierarchy Open Create Symbol for Schematic 2 A graphical symbol editor window will be opened with a default symbol generated from the number orientation and names of the module ports on the schematic 3 The symbol created can be saved straight away or you can edit it to suit your requirements To save it in the symbol editor window select the menu File Save You will not usually need to change any of the settings in the dialog Just press Ok to close Navigating Hierarchical designs There are a number of means of navigating hierarchical designs You can go up or down one level or you can jump straight to the top level or root 81 User s Manual 82 Descending into a Block 1 Select the block then either press Control E or select Hierarchy Descend Into 2 Ifschematic attached to the block is already open it will be brought into view If it isn t it will be opened Note that the schematic will now be associated with the block that you entered This is important if you have more than one block attached to the same schematic and you intend to plot curves from it after a simulation This is explained more fully in the section on simulating hierarchical designs Ascending to Parent Schematic 1 Selec
59. and Data Analysis If xEnd is specified Y2 y value at xEnd otherwise Y2 minimum y value in data Implemented by built in script uf_fall See install CD for source Frequency Frequency data threshold Finds the average frequency of data Returns n 1 x x Where n the number of positive crossings of threshold x the x value of the nth positive crossing of threshold x the x value of the first positive crossing of threshold If threshold is not specified a default value of ymax ymin 2 is used where ymax is the largest value in data and ymin is the smallest value Implemented by built in script uf_frequency See install CD for source HPBW HPBW lt data db_down Finds high pass bandwidth Y max db_down Returns the value of X1 as shown in the above diagram Y max is the y value at the maximum point X max is the x value at the maximum point 273 User s Manual 274 X1 is the x value of the first point on the curve that crosses Y max db_down starting at X max and scanning right to left Note that data is assumed to be raw simulation data and may be complex It must not be in dBs Implemented by built in script uf_hpbw See install CD for source LPBW LPBW lt data db_down Finds low pass bandwidth X max x1 1 Y max db_down Returns the value of X1 as shown in the above diagram Y max is the y value at the maximum point X max is the x value at the maximu
60. and must not be specified if dual mode operation is required The following dialog will be displayed when you edit a capacitor or inductor 137 User s Manual 138 tl Choose Component Value Device Value Initial Conditions Base 1 Series Open circuit Enable For Analysis Decade 1n O E6 Initial voltage Op E12 7 m Transient O E24 Result 1r j The device value is edited in the same manner as for resistors You can also supply an initial condition which defines how the device behaves while a DC operating point is calculated For capacitors you can either specify that the device is open circuit or alternatively you can specify a fixed voltage For inductors the device can be treated as a short circuit or you can define a constant current Important note to experienced SPICE users The initial condition values above do not require the UIC or Skip DC bias point option to be set This implementation of initial condition is a new feature not found in standard SPICE If an initial condition for a capacitor is defined it will behave like a voltage source during the DC operating point calculation Similarly an inductor will behave like a current source if it has an initial condition defined Potentiometer The potentiometer may be used in both SIMetrix and SIMPLIS modes To place select the menu Place Passives Potentiometer This device can be edited in the usual manner with F7 Edit Part popup Th
61. are one of the schematic editor s most important concepts They are actually used for a number of purposes but the most importantly they are used to determine how a schematic device behaves during simulation A property tells the simulator what type of device it is resistor BJT sub circuit etc another property specifies a device s value or model name and for a hierarchical block a property specifies the file location of the underlying schematic For most applications you only need to understand the meaning of ref value and model properties These are explained below but also in Properties on page 90 It is also useful but not essential to understand the schematic_path property used in hierarchical blocks Chapter 4 Schematic Editor What is a Property A Property is an item of text that is attached to a schematic component to specify some circuit parameter such as a component reference e g R23 value e g 2 2K or model name e g BC547 All properties have a name a value and a number of attributes A property s value may be displayed on the schematic The attributes determine how the value is displayed with the exception of the protected attribute which determines whether a property is allowed to be modified A property can have any name as long as does not have spaces in it and any value However certain property names have a special meaning and impart a particular functionality on the component that owns it These
62. at PRINT step The simulator generates data at a variable time step according to circuit activity If Output all data is checked all this data is output If Output at PRINT step is checked the data is output at a fixed time step regardless of the activity in the circuit The actual interval is set by the PRINT step This is explained below If the Output at PRINT step option is checked the simulator is forced to perform an additional step at the required interval for the data output The fixed time step interval data is not generated by interpolation as is the case with generic SPICE and other products derived from it Start data output No simulation data will be output until this time is reached PRINT step PRINT is a simulator command that can be specified in the netlist to enable the output of tabulated data in the list file See Simulator Reference Manual for details of PRINT The value specified here controls the interval used for the tabulated output provided by PRINT but the same value is also used to determine the data output interval if Output at PRINT step is specified see above Real Time Noise See page 187 Monte Carlo and Multi step Analysis See page 194 Advanced Options Opens a dialog as shown below 171 User s Manual 172 e Transient Advanced Options K Time step Max time step 20u Min time step 20f Default Integration method Miscellaneous Trapezoidal integration
63. be opened run in an existing instance of SIMetrix if there is one That is a new instance will not be started unless none are already running n Inhibits the display of the splash screen Inactive for version 5 1 as this does not display a splash screen c config_location This identifies where SIMetrix stores its configuration settings config_location should be of the form PATH file_pathname 323 User s Manual file_pathname identifies the location of a file to store the configuration settings You may use any of the system constants defined in Definition on page 321 in this definition of file_pathname E g EXEPATH for the executable directory See Configuration Settings below for details of configuration settings The REG syntax available with earlier versions is no longer supported f features Specifies which features are enabled See Mixed Feature Licenses on page 26 for more information about this option Using startup ini Start up parameters can also be specified in a file called startup ini On Windows this must be located in the same directory as SIMetrix exe On Linux the file must be located at HOME simetrix startup ini The format of the file is as follows StartUp settings settings can be any combination of the following StartupScript startup_script equivalent to s on command line UsePrevinst equivalent to i on command line InhibitSplash equivalent to n on
64. behaviour You may need to use this if using a non standard XP theme Default sxappdatapath user_v2 Location and base name without extension of the user catalog file Alternative location for user scripts See Script Reference Manual for more information Path of directory where the user s symbol libraries are stored Default sxappdatapath SysSymbols Location of symbol libraries containing edits to system symbols Default false If true a small graph cursor will be used instead of the full crosshair No Options dialog No Cursors Cursor Style 343 User s Manual 344 Name VertTextMode WarnSubControls WireWidth WorkingCatalog unsupported File Extension Type Text Boolean Numeric Text Description User interface support Default Alt No Controls vertical text display when copying graphs to the Windows clipboard Default setting has been found to be reliable and it isn t usually necessary to change it If you find a target application does not display the y axis labels correctly try values of Normal use a different method to rotate text Hide hides vertical text or Horiz displays vertical text horizontally Default false No If true a warning will be issued if unexpected simulator commands are found in subcircuits Width in pixels of No schematic lines Default 1 Default sxappdatapath No out Location and base
65. box Placing Symbol If a schematic sheet is open you can place a symbol on it directly from the library manager by pressing the Place button Note that this will close the dialog box Editing System Symbol Libraries The system symbol libraries are listed in the file SystemLib sx st located in the symbol libraries folder The libraries are treated specially when written to e g when editing any symbol in the library System symbol libraries are protected from being edited directly You can still edit the system symbols but the changes are stored separately in an ASCII file located in a directory in the application data area This scheme protects such changes from being lost when the system symbol libraries are updated during a service update The system symbol libraries are stored in a directory defined by the SymbolsDir option variable see page 341 On Windows this is typically located at C Program Files SIMetrixXX support symbollibs and on Linux usr local simetrix_xx share symbol libs The directory where system library edits are stored is defined by the UserSystemSymbolDir option variable see page 343 PSpice Schematics Translation An optional extra feature of SIMetrix is the ability to read schematic files created by the PSpice Schematics program Note that it cannot read Orcad Capture files Configuring the Translator Before using this facility it must be configured This is simply a matter of specifying the loca
66. by a E g U Filter C1 10n alpha 1 freq 10k 156 Chapter 6 Device Library and Parts Management Chapter 6 Device Library and Parts Management Overview The electrical characteristics for semiconductor devices such as transistors and for more complex devices such as operational amplifiers are not built in to the simulator program but are defined in separate library files These are text files containing MODEL and SUBCKT controls Some libraries have been supplied with SIMetrix but you can obtain others from device manufacturers usually at no cost and other model vendors You can also create them yourself using a text editor Many vendor libraries may be downloaded from the Internet Our World Wide Web site carries a page with links to vendor sites URL is http www catena uk com site support models html This section explains how to use install and manage parts libraries Important The library and parts management systems described in this chapter work with discrete devices defined using subcircuits and MODEL statements It currently does not support process corner selection and process binning used by many models supplied by integrated circuit process foundries See Using Schematic Editor for CMOS IC Design on page 119 for details on how to handle such libraries Using Parts Browser The parts browser provides a convenient method of selecting a component Parts are arranged in categories to allow for rapid s
67. by comparing file dates All index files are stored in app_data_dir INDEXES where app data dir is the location of the application data directory See Application Data Directory for the location of this directory The files are named SXn sxidx where n is some number Note that if you add a new model file to a directory while SIMetrix is running SIMetrix won t know of the new file and any relevant indexes won t be updated In this situation select the menu File Model Library Rebuild Catalog to update the indexes Duplicate Model Names Models of some common parts are available from different sources Sometimes these have different names e g LF356 and LF356 NS the latter available from the National Semiconductor library In some cases the model names from different sources are identical This poses a problem as models have to be uniquely identified by their name Chapter 6 Device Library and Parts Management SIMetrix has a built in utility that can automatically rename models with duplicate names The devices are renamed by adding a user specified suffix to the model name The rename utility is not accessible via the menus but must be invoked by typing a command at the command line Proceed as follows 1 First ensure that all the model library files you wish to process are installed as global libraries 2 Make backup copies of your model files This is optional the utility makes backups anyway 3 Type at the command line i
68. case the following priorities apply 1 User supplied association e g using the associate symbols and models dialog takes precedence over embedded association 2 Embedded association takes precedence over pre defined association Pre defined association is what is stored in the ALL CAT catalog file supplied with SIMetrix Catalog Files The data for model and symbol associations are stored in catalog files There are three catalog files as follows ALL CAT USER_V2 CAT OUT CAT Resides in SIMetrix root directory Stores catalog data supplied with SlMetrix SIMetrix never modifies this file Resides in the application data directory see Application Data Directory on page 325 Stores catalog data supplied by the user Data in this file overrides data in ALL CAT The Associate Models dialog box writes to this file In SIMetrix versions 5 2 and earlier this file was called USER CAT SIMetrix will automatically import data from USER CAT to USER_V2 CAT if USER CAT is present Resides in application data directory see Application Data Directory on page 325 This is what is actually used by the parts browser to select and place components It is generated by the associate model dialog box from information in ALL CAT USER_V2 CAT and installed models It will also be automatically created by the parts browser if it does not already exist You can also force it to be rebuilt at any time by selecting menu File
69. command line ConfigLoc config_location equivalent to c on command line Features features equivalent to f on command line Configuration Settings 324 Overview SIMetrix in common with most applications needs to store a number of values that affect the operation of the program These are known as configuration settings Included among these are the locations of installed symbol libraries installed model libraries font preferences colour preferences and default window positions Default Configuration Location By default SIMetrix stores configuration settings in a single file This file is located at simetrix_app_data_dir vXX Base sxprj Replace XX with the version number E g 51 for version 5 1x See Application Data Directory below for location of simetrix_app_data_dir Chapter 13 Sundry Topics Application Data Directory SIMetrix stores a number of files in its application data directory On the Linux platform this is simply at HOME simetrix On Windows the directory is at this location sys_application_data_dir Catena Software SIMetrix Where sys_application_data_dir is a system defined location With full versions of SIMetrix you can locate this directory by typing this command at the command line Show TranslateLogicalPath sappdatapath The following table shows typical locations for all supported Windows systems Operating Path System Windows 2000 C Documents and Settings username Ap
70. data systems and oscillators for which AC noise analysis is not appropriate Real time noise is not available with all versions of the product Contact sales for details Setting Up a Real Time Noise Analysis 1 2s 3 Select menu Simulator Choose Analysis Select Transient check box on the right Select Transient tab at the top Enter parameters as described in the following sections Set up transient analysis parameters as detailed on page 170 Check Enable real time noise Select Define to set up real time noise parameters Enter values as explained below 187 User s Manual Interval This specifies the sampling interval of the noise generators You should set this to a maximum of about 1 3 of the highest noise frequency of interest Note that the interval also forces a maximum time step so short intervals can result in long simulation times Start time The time at which the noise generators are switched on Defaults to 0 Stop time The time at which the noise generators are switched off This defaults to the stop time of the transient run If you think you may wish to restart the transient run after it has completed and you wish the noise generators to continue to be enabled after the restart then you must specify this time beyond the initial stop time before starting the analysis You should avoid however using inappropriately large values for this stop time as this may noticeably slow the simulation an
71. devices can be defined with a set of simulator parameters However not all devices are implemented directly by the simulator It does not for example have a operational amplifier device built in These components are constructed from a number of other components into a subcircuit The devices built in to the simulator are described in the Simulator Devices chapter of the Simulator Reference Manual Numbered Components Numbered components may be accessed via the Parts Browser Select menu Place From Model Library to open it This is what you will see 125 User s Manual Fl select Device pe tan la RFS20NS IR IRF540S IRF611 IGBTs RF520S inf5402 IRF612 Instrumentation Amplifiers RFD IRESI FRIE Tarnen RF522 IRF542 inf6156 Miscellaneous RF523 IRF543 IRF620 MOSFETs dual IRF530 irf5801 IRF620 1R N channel JFET l RFS30 IR inf5802 IRF620F NMOS RF530_SS inf5852 IRF620S NPN RFS30FI inf5m3205 IRF621 snes RF530N inf5m3415 IRF622 P channel JFET RF530N 1R if5m3710 IRF623 PMOS RF530NS irf5n3205 IRF624 RFS30NS IR irf5n3415 IRF630 fo ee Oe enone RF530S if5n3710 IRF630 R ie inf530v inf5nj3315 IRF630FI f Bre RF531 inf5nj540 IRF630S t WIS g RF532 inf5ni248 IRF631 o Fos RF533 ifSy31n20 IRF632 t MER te RF540 inf5y3315cm IRF633 TET RFS40 1R inf5y3710cm IRF640 t sori ot RF540FI irf5y5400m IRF640 1R er RF540N IRF610 IRF640FI t gat 23 RF540N 1R IRF610 1R itf640ns P oF
72. devices support vector connections and or variable type connections These are designated in the netlist with the characters and and are explained in the Digital Simulation chapter of the Simulator Reference Manual You can add these to a symbol by prefixing the appropriate pin name with the same characters as required in the netlist E g to start a vector connection at a pin named IN1 enter the pin name IN1 To close a vector connection at pin IN3 use pin name IN3 Similarly to change a connection whose default type is v i e a single ended voltage to a differential current type id prefix the first pin name with id and a space E g pin name VIN would become id VIN Examples of the use of vector connections in symbols can be found with any of the digital gate symbols Defining Properties Properties define the behaviour of the symbol For full documentation on the use of properties see section Properties on page 102 In this section the methods of adding and editing properties in the symbol editor are described Adding a Single Property To add a property to a symbol select Property Pin Add Property You will see the following dialog box 97 User s Manual 98 A Add Property Name Value Text Location Property Attributes Auto Font style Default x Normal Left m C Selectable Allows symbol to be selected by clicking in property text Bisteted Lef
73. e the edit box below the menu bar in the command shell rename_libs 4 A list of currently installed libraries will be displayed Double click on any that you wish to be processed for renaming and supply a suffix The suffix must not contain spaces and should start with a non alphanumeric character such as or Note that only models found to have duplicates will be renamed SIMetrix will not rename unique models If you do not supply a suffix for a library no devices within it will be renamed 5 Press OK The operation can take a long time possibly a few minutes if the library is large On completion the message RENAME COMPLETE See RENAME LOG for details will be displayed in the command shell The RENAME LOG file will contain full details of the rename process This includes details of all models that were renamed Notes If the device being renamed is implemented as a subcircuit the rename utility will copy any symbol model association for that device with the new name Devices that are used locally i e within the model file itself will be excluded from the rename procedure These devices will not be renamed nor will they added to the list that is searched to identify duplicate names You can perform a test run which creates the log file but does not actually perform the renaming To do this type the command rename_libs_ check Note that messages output to the log file and to the command shell will report the re
74. ee 325 Using the Options Dialog 0 0 0 eeeeeeeeeteeeeeee 326 Using the Set and Unset commands eee 331 Startup Auto Configuration s e 346 OVGIVIEW kiaiii iriiri 346 What is Set Upi deresine aeae arire iiai erei 346 Auto Configuration Options eeeeeee 346 Installation CUStOMISING ee eee eeeeteeeeeeeeee 348 Colours and Font keia aait 348 COlOUIS tae eae eA ee 348 POMS E E EA 348 Using a Black Background sses 350 User Defined Key and Menu Definitions 0 350 Menu Short cuts ieee rererere 350 User Defined Toolbars and Buttons eee 350 Startup Scripties iaeiaiai 351 Chapter 1 Introduction Chapter 1 Introduction Installation Windows Version Installation If you are upgrading from an earlier version you must install to a new folder Your previous version will continue to function as before See below for information on upgrading Procedure Installing from CD Insert CD If AutoRun is enabled a simple dialog box should appear automatically If not execute SETUP EXE in the Setup directory of the CD You should always install SIMetrix to a local drive By modern standards it is a compact application occupying less than 40MBytes so therefore consumes negligible resources While SIMetrix will run satisfactorily from a remote network drive Upgrading If you are upgrading an earlier version of SIMetrix when you run SIMetrix 5 3 for the first time you will be asked if you w
75. enee deities al Editing AXES 1 2 40 ia eee Reordering Grids and Digital Axes Plotting the Results from a Previous Simulation 239 Combining Results from Different Runs 240 Curve Operations ecceeeseceeeeeeeeeeecenaeeesneeeensaeeeneaes 241 Selecting CUrVES 0 0 eens ceeeneeeneeeeesteeeeenaeeeeenaees 241 Deleting Curves cs ceccscnecssncrteedeeeneseenecdenesecndenees 241 Hiding and Showing Curves ceeeseeeseeeeeeeeee 241 Re titling CUVES isini eee eeeeteeeeeeeeeeneeeteaeeeeneeeenea 241 Highlighting Curves eeren 242 Graph Cursors 22 8 aide a a 242 OVEIVIOW einna een MA ee 242 Cursor Operations eeren 243 Additional Cursors eeeeeeeeeeeriesrrieerrieerisreene 244 Cursor Reado t iiit edd 245 Cursor Functions inainte ir 247 Curve Measurement ccecccesceeesereeeenneeeeeeeeeenaeeeeeaes 247 OVOGIVIEW ieir iarsi ira ie aiea 247 Available Measurements 247 Repeating the Same Measurement nsee 251 Notes on Curve Measurement Algorithms 251 Plots frOM CUIVES 0 0 cece eeeeeeseeeeeneeeeeneeteeeeeeeneeeeeaa 253 Graph Zooming and Scrolling 253 Anmotating a Graph ee eeee eee cenneeeseeeeeeeneeeeeneeeenneeees 254 Curve Maker Ss civier iini etie 254 Legend BOX ienien i onien ea a 256 Table of Contents Text BOX avastar eheslint enh aceeedvabesncensbemeiincs 257 Caption and Free Text cccccceeeeeeteeeeeeeeeeeeeees 257 Copying to the Clipboard 0 0
76. extension is omitted in the model FILE parameter this will be used Scripts Default extension for scripts if called without an extension Device models SPICE model files For future expansion currently unused Device catalogs Extension for device catalogs used by parts browser system Using the Set and Unset commands All options have a name and many also have a value These are set using the Set command page 297 and can be cleared with UnSet page 298 When an option is cleared it is restored to its default value A complete listing of available options with possible values is given below Note that option settings are persistent This means that their values are stored either in the INI file or in the system registry see Configuration Settings on page 324 and automatically restored at the start of each subsequent SIMetrix session List of Options Upper and lower case letters have been used for the option names in the following listing only for clarity Option names and their values are not in fact case sensitive Many of the options described below are supported by the Options dialog box in which case they are noted accordingly Unsupported Options Some options in the following list are marked as unsupported This means that they may be withdrawn in the future or their functionality changed 331 User s Manual 332 Name Type Description User interface support 700Extensions Boolean Schematic symbols
77. find the current in a sub circuit device or hierarchical block it can also calculate such a device s power Be aware however that as this power is calculated from the VI product of the device s pins the calculation may be inaccurate if the sub circuit uses global nodes Chapter 9 Graphs Probes and Data Analysis Plotting Noise Analysis Results Small signal noise analysis does not produce voltage and current values at nodes and in devices in the way that AC DC and transient analyses do Noise analysis calculates the overall noise at a single point and the contribution of every noisy device to that output noise Optionally the input referred noise may also be available To Plot Output Noise 1 Select menu Probe AC Noise Plot Output Noise To Plot Input Referred Noise 1 Select menu Probe AC Noise Plot Input Noise Note that you must specify an input source for input referred noise to be available See Noise Parameters on page 184 for details To Plot Device Noise 1 Select menu Probe AC Noise Probe Device Noise 2 Click on device of interest Note that noise results are only available for noisy devices such as resistors and semiconductor devices Plotting Transfer Function Analysis Results No cross probing is available with transfer function analysis Instead you must use the general purpose Define Curve dialog box With this approach you must select a vector name from a list Proceed as follows 1 Select menu Probe
78. flop Set reset flip flop clocked J K flip flop D type flip flop Toggle flip flop Latch Simple switch voltage controlled Simple switch current controlled Transistor switch voltage controlled Transistor switch current controlled VPWL Resistor IPWL Resistor PWL Capacitor PWL Inductor Saturable Inductors and Transformers SIMetrix is supplied with a number of models for inductors and transformers that correctly model saturation and for most models hysteresis As these components are nearly always custom designed there is no catalog of manufacturers parts as there is with semiconductor devices Consequently a little more information is needed to specify one of these devices This section describes the facilities available and a description of the models available Core Materials The available models cover a range of ferrite and MPP core materials for inductors and transformers with any number of windings The complete simulation model based on a library core model is generated by the user interface according to the winding specification entered Placing and Specifying Components 1 Select the menu Place Magnetics Saturable Transformer Inductor You will see the following dialog box 133 User s Manual 134 e Define Saturable Transformer Inductor Configuration Define windings Primaries 1 Aj Select winding Sec 1 1 M Primary tums 100 4 Secondaries 1 A Ratio to primary 1 1 s Coupling factor
79. for the nth time with a positive slope Chapter 9 Graphs Probes and Data Analysis XatNthYpct XatNthYpct data yValue n As XatNthY but with yValue specified as a percentage of the maximum and minimum values found in the data YatX YatX data x Value Returns the y value of the data at x value x Value YatXpct As YatX but with xValue specified as a percentage of the total x interval of the data Data Import and Export SIMetrix provides the capability to export simulation data to a file in text form and also to import data from a file in text form This makes it possible to process simulation data using another application such as a spreadsheet or custom program SIMetrix may also import data in SPICE3 raw file format and CSDF format Some other simulation products can output in one or both of these formats Importing SPICE3 Raw and CSDF Files 1 Select command shell menu File Data Load 2 In Files of type select SPICE3 Raw Files or CSDF Files as required 3 Select file to import SIMetrix will read the entire file and write its data out to a temporary sxdat file in the same way as it does when saving its own simulation data The data read from the raw file is buffered in RAM in order to maximise the efficiency of the saved data SIMetrix will use up to 10 of system RAM for this purpose Note that this feature is not available with SIMetrix Intro Importing Tabulated ASCII Data SIMetrix can import data in a
80. interval if there is a conflict Periodic Operating Point POP Periodic Operating Point POP finds a steady state operating point of switched systems that are periodically driven or self oscillating The predominant application of this analysis mode is to rapidly find the settled condition of a switching power supply without having to simulate the entire power up sequence This dramatically speeds up the analysis of design s behaviour under different load conditions For further details of POP analysis see the SIMPLIS Reference Manual 203 User s Manual 204 Setting up a POP Analysis 1 Select menu Simulator Choose Analysis 2 Select POP check box on the right 3 Select POP tab at the top Enter parameters as described in the following sections POP Parameters Triggering Use POP Trigger Schematic Device POP analysis requires a trigger signal to indicate the start of each periodic cycle The best way to define this is using a special schematic component To place this select menu Place Analog Functions POP Trigger You should check this box if you are using this component Trigger gate If you do not use the schematic POP trigger device see above you must specify a suitable component in this edit box Enter the full component reference of the device Trigger Condition The polarity of the trigger edge Conditions Max period You should set this to a value that is larger than the expected period of your circ
81. is placed on the schematic Devices currently supported are MOSFETs BJTs and diodes In the case of MOSFETs and Zener diodes the conversion is achieved by performing a sequence of simulations using the SIMetrix SPICE simulator This method is independent of the method of implementation of the device Chapter 1 Introduction Why Simulate Integrated circuit designers have been using analog simulation software for over two decades The difficulty of bread boarding and high production engineering costs have made the use of such software essential For discrete designers the case has not been so clear cut For them prototyping is straightforward inexpensive and generally provides an accurate assessment of how the final production version of a circuit will behave By contrast computer simulation has been seen as slow and prone to inaccuracies stemming from imperfect models In recent years however the simulation of discrete analog circuits has become more viable This has come about because of the almost relentless advances in CPU power the increased availability of device models from their manufacturers and the introduction of easy to use and affordable simulation tools such as SIMetrix The pressure to reduce product development time scales has meant that for many projects the traditional bread boarding phase is skipped altogether with or without simulation and circuit development is carried out on the first revisions of PCB The use of
82. made in block2 without them having to be passed via the parent block1 The above trivial example is supplied as an example See Examples Hierarchy Global Pins Creating Global Pins To define a global pin select the symbol editor menu Property Pin Global Pins Double click on the pin you wish to assign as global and select Yes Passing Parameters Through a Hierarchy To pass parameters through a hierarchy assign a PARAMS property then give it a value to assign each parameter you wish to pass e g PARAM1 10 PARAM2 57 See supplied example in folder Examples Hierarchy Passing Parameters Missing Hierarchical Blocks When a hierarchical schematic is opened SIMetrix needs to locate the component files that contain the symbols used for each hierarchical block If however the file for a particular component is missing or is in the wrong location then SIMetrix will not be able to display that component s symbol Unlike library symbols component symbols are not stored locally in the schematic file In order to make it possible to resolve the problem SIMetrix instead puts a place holder symbol in place of the missing symbol The place holder symbol is a diagonal cross Repairing Missing Components Ifa component is missing you can either edit the schematic to identify the new location of the component or you can move files around so that the components are once again in the expected locations To edit the schematic select th
83. method This is the frequency interval at which the spectral components are evaluated It cannot be less than 1 T where T is the time interval over which the spectrum is calculated Start Freq Hz Start frequency of the display Stop Freq Hz Stop frequency of the display Log X Axis Check this to specify a logarithmic x axis This will force a minimum value for the start frequency equal to 1 T where T is Chapter 9 Graphs Probes and Data Analysis the time interval being analysed Signal Info If the signal being analysed is repetitive and the frequency of that signal is known exactly then a much better result can be obtained if it is specified here Check the Know fundamental frequency box then enter the frequency The Fourier spectrum will be calculated using an integral number of complete cycles of the fundamental frequency This substantially reduces spectral leakage Spectral leakage occurs because both the Fourier algorithms work on an assumption that the signal being analysed is a repetition of the analysed time interval from t to t oo If the analysed time interval does not contain a whole number of cycles of the fundamental frequency this will be a poor approximation and the spectrum will be in error In practice this problem is minimised by using a window function applied to the signal prior to the Fourier calculation but using a whole number of cycles reduces the problem further Note that the fundamental frequency is not neces
84. mod line 14 al Opamp e e e i Inverting input l Non inv input pza EE Chapter 6 Device Library and Parts Management 5 Enter a suitable category for the part under Choose Category for xxx where xxx is your model name You can create a new category if desired by pressing New Category 6 Using the drop down box under Define Symbol for xxx select a suitable symbol for your model An image of the symbol will be displayed so you can check if it is appropriate If no suitable symbol is available press Auto Create Symbol and one will automatically be created You can edit this symbol later if required 7 Ifyou selected an existing symbol you must check that the pin order matches that of the model itself The model text is displayed under Electrical Model xxx If the pin order needs changing use the up and down arrow keys to rearrange the pins as appropriate 8 Press Ok then place symbol as usual Steps 4 to 8 above only need to be done once for each model Note If the message Unknown file type xxx is displayed when you drop a file it means that no valid SPICE models were found in the file It does not mean the file has the wrong extension SIMetrix will accept any extension for model files with the exception of the extensions used for schematic or graph files sch sxsch and sxgph Removing Model Libraries Select Model Library View Remove Libraries A dialog
85. model available as a standard part but you will not be able to subsequently modify it other than by re entering the specification manually If you choose this option you must specify a device name in the box below 4 Press Ok to place diode on the schematic If you selected Save to model library the model file for the device will also be created at this point The file will be saved in your user models directory On windows this is located at My Documents SIMetrix Models and on Linux it is at SHOME simetrix Models Soft Recovery Diode Specification The parameter extractor allows the specification of three important characteristics of the diode These are the DC forward bias voltage reverse recovery and capacitance Currently reverse leakage and breakdown characteristics are not modelled To specify the forward bias characteristics simply enter the coordinates of two points on the graph showing forward drop versus diode current which is found in most data sheets You should choose values at the extremes The low current value will essentially determine the value of the IS parameter while the high current value defines the series resistance of the device The reverse recovery characteristics are explained in the following diagram gt lt r dif dt IRM 37 IRM The values quoted in data sheets vary between manufacturers The value given for Tr is sometimes taken from the reverse peak rather than t
86. model parameter differences then the snapshot data may be accepted without error but at best the results will need careful interpretation and at worst will be completely erroneous Generally if you change a component that affects the DC operating point then the results will not be meaningful If you change only an AC value e g a capacitor value then the results will probably be valid How Snapshots are Stored The snapshot data is stored in a file which has the default name of netlist sxsnp where netlist is the name of the netlist used for the simulation When using the schematic editor this is usually design net so the usual name for the snapshot file is design sxsnp You can override this name using the SNAPSHOTFILE OPTIONS setting although there is rarely any reason to do this The snapshot file is automatically deleted at the start of every transient run The SaveSnapShot command always appends its data to the snapshot file so that any pre defined snapshots are preserved When snapshot data is applied to a subsequent small signal analysis the snapshot file is read and checked that it is valid for the circuit being analysed Applying Snapshots to a Small Signal Analysis 1 Select menu Simulator Choose Analysis 2 Press Define Multi step Analysis for the required analysis mode 3 Select Snapshot mode The above procedure will result in the small signal analysis being repeated for each snapshot currently available Operating
87. mouse mode will revert to normal select mode It is easier to demonstrate than explain You may wish to experiment with arc circle ellipse drawing to gain a feel of how the system operates You will note that full circles are displayed with a small filled square on opposite sides These are the select points You can pick either one and drag it to resize the circle Placing and Defining Pins Placing a Single Pin To place a single pin select Property Pin Place Pin Place this on the sheet by left clicking the mouse at your desired location Note that pins always snap to major grid points See diagram in section Symbol Editor Window on page 93 The first pin you place on the sheet will be called pin The signifies that the pin name will not be visible when the symbol is placed on a schematic Editing Pin Attributes To edit the attributes of the pin e g to change its name or visibility select either the pin or its label with the left mouse key then press F7 or select popup menu Edit Property Pin Arc This will display the following dialog PS Edit Pin Pin name P Text Location Justification Left Baseline Pin name will be hidden hee on schematic Text will be rotated C Vertical by 90 degress Attributes Font style Default Iw Pin name Must be unique within the symbol and may not contain spaces 95 User s Manual 96 If the symbol is to be used as a hiera
88. points to be generated These will be evenly spaced within the start and stop times Chapter 8 SIMPLIS Analysis Modes Advanced Pressing the Advanced button opens the following dialog is Transient Advanced Options Snapshot output Cancel Snapshot interval 0 xi 4 4e Max snapshots 11 Help Snapshot output SIMPLIS has the ability to save its internal state in order to allow a run to be repeated from a certain time point This allows a run to be continued from where it previously left off Similar to SIMetrix transient restart facility The internal saved states are known as snapshots SIMPLIS always saves a snapshot at the end of every run so if you start a new run of the same circuit with a start time Start Saving Data equal to the stop time of the previous run SIMPLIS will not need to rerun the start and instead will load the snapshot state SIMPLIS will do this automatically The entries in this dialog section allow you to specify the saving of snapshots at other times as well as the end of a run This might be useful if you wanted to restart a run at some before the end of the previous run Enable snapshot output Check this box to enable saving of snapshot data Snapshots are always saved at the end of a run Snapshot interval This is the minimum duration between snapshots Max snapshots This is the maximum number of snapshots that will be saved This setting overrides Snapshot
89. setting Select menu File Options General then in the Schematic sheet select Classic under the Double click mode section CMOS Transistor Symbols A new set of NMOS and PMOS schematic symbols for CMOS IC design have been developed which are simpler and easier to use The old symbols are still present but have been relocated to Obsolete gt Semiconductors gt MOSFETs IC Please see Using Schematic Editor for CMOS IC Design on page 119 for information on the new symbol design 31 User s Manual Chapter 2 Quick Start Tutorials Overview 32 This chapter covers a number of tutorials that will help you get started with SIMetrix Tutorial 1 is designed for total novices You may wish to skip to tutorial 2 if you already have experience with SPICE type programs Tutorial 2 assumes you have grasped the basics of using the schematic editor You don t have to worry about setting up analyses or the characteristics of any input stimulus such as V2 in tutorial 1 these procedures will be explained If you are an experienced circuit designer but have never used a circuit simulator before we recommend you read Simulation for the Novice below This will familiarise you with a few concepts about simulation that may be alien to you if you are used to traditional methods of evaluating circuits Examples and Tutorials Where are They In Linux the examples and tutorials reside in the examples tar file that forms part
90. should be set to the maximum current rating of the device The conversion process needed to create the SIMPLIS model is often able to look up this value in a database If not you will be prompted to enter a suitable value BJTs Model level This may be set to 1 or 2 1 runs faster while 2 provides more accurate results See diagrams below for model structures used Max Collector Current Set to specified maximum collector current for device MOSFETs Peak Operating current This should be set to the peak operating current expected during circuit operation The parameter extraction process will work out a suitable value which is often satisfactory Model level Values are 0001 0011 1032 0001 is the simplest and fastest while 1032 provides the greatest detail and is the slowest Zener Diodes Maximum Power Set this to the maximum rated power for the device The conversion process needed to create the SIMPLIS model is often able to look up this value in a database If not you will be prompted to enter a suitable value Chapter 5 Components SIMPLIS Models D1 O S LEVEL 0001 MOSFET D E T S LEVEL 0011 MOSFET 129 User s Manual i LEVEL 1032 MOSFET Cc O B0 IRBE Ay S1 LEVEL 1 BJT Model 130 Chapter 5 Components izalphaF X I IRBE je od RB izalphaR XI RBC ie LEVEL 2 BJT Model Generic Components As
91. signal will be at the Initial value until the delay period has elapsed 56 SIMPLIS is available with the SIMetrix SIMPLIS product Chapter 3 Getting Started 7 Note that some parameters can be specified in more than one way For example both frequency and period edit controls are supplied Changing one will cause the other to be updated appropriately The same applies to duty and width and the vertical controls in the lower half A Cosine wave shape combined with a positive delay and with Off until delay checked will only function correctly in SIMPLIS mode PWL Source This device can be used to describe a piece wise linear source A PWL source can describe any arbitrary wave shape in terms of time voltage or time current pairs To place a PWL source select menu Place Sources PWL Source or Place Sources PWL Current Source To edit the device select it and press F7 or Edit Part popup menu This will open the Edit PWL Dialog which allows you to enter time and voltage current values As well as entering values individually you can also paste them from the Windows clipboard by pressing the Paste button or control V The values can be copied to the clipboard using a text editor The values may be separated by spaces tabs commas or new lines PWL sources may be used in both SIMetrix and SIMPLIS modes When defined in this way PWL sources are limited to 256 points In SIMetrix mode much larger PWL sources may be defined See th
92. simulation on a circuit or parts of a circuit can help to eliminate errors in a circuit design prior to this stage and reduce the number of PCB revisions required before the final production version is reached Of course to be useful the simulation process must therefore not be too time consuming Computer simulation does however have many more uses There are some things you can do with a simulator which cannot be achieved with practical approaches You can remove parasitic elements you can make non invasive measurements that are impossible in real life or you can run components outside of their safe operating area These abilities make simulation a valuable tool for finding out why a particular design does not behave as expected If the problem can be reproduced on a simulator then its cause can be much more easily identified Even if a problem cannot be reproduced then this gives some clues It means that it is caused by something that is not modelled a wiring parasitic perhaps Simulation is extremely useful for testing ideas at the system level Sometimes it is not easy to test a concept because the hardware to implement it is very costly or time consuming to build It may even be that you don t know how to implement the idea in hardware at all The alternative is to design a model and simulate it with a computer Once it has been established that the concept is viable then attention can be given to its implementation If it proves not to be
93. special properties are described in the following table 103 User s Manual 104 Property name Function ref value model Component reference E g R23 All circuit devices must have this property and its value must be unique Component value or model name E g BC547 All circuit devices must have this property This may be confusing What is described here is a property of name value not the property s value Single letter to signify type of device For list of signifying letters for each device supported by simulator see Summary of Simulator Devices on page 122 If absent the first letter of the component reference will be used instead as for SPICE For example a device with a model property of value Q will always be a BUT regardless of its component reference model properties of X H and F have a special significance as follows X Subcircuit instance pinnames specifier will be added to inform simulator of the devices pin names The simulator will then choose names for device current vectors which will allow cross probing of currents from the schematic F Current controlled current source The standard SPICE CCCS is a two terminal device which uses a separate voltage source for the controlling current SIMetrix provides the facility to use a single four terminal device with pins 3 and 4 for the controlling current and pins 1 and 2 for the output Any symbol with four terminals and a mod
94. sweep the frequency over the range specified by Start frequency Stop frequency and Number of points or Points per decade if you select a decade sweep You will also need to enter some additional parameters Noise parameters Output node Use Terminal symbol to Pernod assign names optional for output and Source name optional ref optional nodes 61 User s Manual 62 An entry in the Output node box is compulsory It is the name of the circuit node as it appears in the netlist Usually the schematic s netlist generator chooses the node names but we recommend that when running a noise analysis that you assign a user defined name to your designated output node You can do this using a terminal symbol Place Connectors Terminal To find out more see Finding and Specifying Net Names on page 80 An entry in the Ref node box is optional It is the node to which the output node is referenced If omitted it is assumed to be ground An entry in the Source name box is optional If specified the noise referred back to it will be calculated Enter the component reference of the voltage or current source that is used as the input to your circuit Frequency sweep is just 1 of 6 modes available with Noise Analysis The Define button allows you to specify one of the others See Noise Analysis on page 183 for details DC Operating Point To specify a DC operating point analysis check the DCOP box on the right of the Choose
95. tabulated ASCII format allowing the display of data created by a spreadsheet program There is a no menu for this but this can be done using the OpenGroup command page 294 with the text switch E g at the command line type OpenGroup text data txt This will read in the file data txt and create a new group called text See Data Files Text Format on page 279 below for details of format 277 User s Manual 278 Note that if you create the file using another program such as a spreadsheet the above command may fail if the file is still open in the other application Closing the file in the other application will resolve this Exporting SPICE3 Raw Files SIMetrix can export all simulation data to a SPICE3 raw file This format may be accepted by third party waveform viewers To export a SPICE3 raw file proceed as follows 1 Select menu File Data Save 2 Under Save as type choose SPICE3 Raw Files Note that various applications use slightly different variants of this format By default SIMetrix outputs the data in a form that is the same as the standard unmodified SPICE3 program This can be modified using the option setting ExportRawFormat Use the Set command to set this value See Set on page 297 for details Set this value to spice3 spectre or other Exporting Data To export data use the Show command page 297 with the file switch E g Show file data txt vout rl_p ql c
96. template NODELIST lt NODELIST gt Replaced by the nodes connected to the device s pins PINLIST lt PINLIST gt Replaced by the symbol s pin names NODE lt NODE n gt Replaced by the individual node identified by n starting at 1 So node 1 is node name connected to the first pin on the symbol PINNAMES lt PINNAMES gt Equivalent to PINNAMES lt PINLIST gt except that no substitution takes place if the nopinnames switch is specified for the Netlist command NODENAME lt NODENAME gt This is not replaced by any text but signifies that the item following is a node name The netlist generator must be able to identify any text that is a node so that it can correctly substitute the name when required For example the following is the template definition of the N channel MOSFET with bulk connected to VSS Smodel ref lt nodelist gt lt nodename gt vss value If VSS were actually connected to ground the netlist generator would replace all nodes called VSS with 0 meaning ground If the lt nodename gt keyword were not present in the above the netlist generator would not be able to determine that VSS is a node and the substitution would not take place 109 User s Manual 110 SEP lt SEP gt Returns separator character used to separate the device letter and component reference This defaults to but can be changed at the Netlist command line See Netlist command syntax in the Script Ref
97. the command shell If you installed individual files you will see a message box asking you to confirm that you wish to continue Just click OK The model files are now installed If you drop folders a search will be made in those folders for SPICE models The Add Remove Models dialog will then be displayed as shown below F Select Libraries x Currently Selected Libraries C Program Files S Metrix50 support Models BB Ib C Program Files S IMetrix50 support Models BB mod C Program Files S IMetrix50 support Models Digital Ib Available Libraries D Sp 4D ClR D Sp Mx Old mod D Sp Mx mod D Sp Polpfet spu Select the items you wish to install in the lower box and transfer them to the upper box by pressing the Add button You can also change the order of the items in the upper box This affects the search order when a simulation is run Press Ok 159 User s Manual 160 You will see a message displayed in the command shell Making Device Catalog This may take some time please wait When finished the message Completed will be displayed The electrical model or models are now installed Placing New Model on Schematic 1 You can now place models installed using the parts browser Select schematic menu Place From Model Library You will see a dialog box similar to that shown on page 126 On the left hand side select category Recently Added Models
98. the same manner as the TEMPLATE property keywords of the same name See Template Property on page 105 for details Note that like template properties the resolution is performed in two passes with the property values being substituted first Adding Standard Properties Select menu Property Pin Add Standard Properties This prompts you for values for the ref value and model properties These properties are usually specified for all symbols with the exception of hierarchical blocks which do not require a Value property If you are using the SIMetrix SIMPLIS product you will also be prompted to supply a value for the SIMULATOR property See Properties You Need to Add on page 91 Editing a Property To edit a property select it then press F7 or select popup menu Edit Property Pin Arc This will open a dialog box very similar to the one described above but without the option to enter a property name Make the appropriate changes then press OK Saving Symbols To save the current symbol select menu File Save The following dialog will be displayed Chapter 4 Schematic Editor e Save Symbol X Define Symbol Save to UserName NPN 3 terminal Library file Intemal Name npn Component file Category Semiconductors BJTs i Current schematic file All references to symbol automatically updated File wApplication Data SIMetrix50 support SymbolLibs semiconductors sxslb Define Symbol
99. this box are stored for future retrieval Use the drop down box to select a previous entry X Expression for X data Only required for X Y plot and you must check X Y Plot box Expression entered in the same way as for Y data Available Vectors Lists values available for plotting This is for finding vectors that aren t on a schematic either because the simulation was made direct from a netlist or because the vector is for a voltage or current in a sub circuit You need to tell SIMetrix to save sub circuit currents and voltages using KEEP for details see page 198 of the Simulator Reference Manual Press Edit Filter to alter selection that is displayed See below The names displayed are the names of the vectors created by the simulator The names of node voltages are the same as the names of the nodes themselves The names for device currents are composed of device name followed by a followed by the pin name Note that some devices output internal node voltages which could get confused with pin currents E g ql base is the internal base voltage of q1 not the base current The base current would be ql b For the vector names output by a noise analysis refer to NOISE on page 206 of the Simulator Reference Manual Edit Filter Pressing the Edit Filter button opens 229 User s Manual A Edit Available Vectors Subcircuit filter Signal type All aa level Voltages only Select subcircuit Currents only
100. to as ALL CAT 335 User s Manual Name Type Description User interface support GridPrintWidth GroupPersistence HideSchematicGrid HighlightIncrement HistoCurveStyle InhibitAutoCD InvertCursors LibraryDiagnostics 336 Numeric Numeric Boolean Numeric Text Boolean Boolean Text Default 0 3mm Options Width of printed graph grid dialog lines in mm See also CurvePrintWidth Default 3 No Sets the number of groups that are kept before being deleted See Plotting the Results from a Previous Simulation on page 239 If set the schematic grid Options will be suppressed dialog Default 1 No Highlighted graph curves are thicker than normal curves by the amount specified by this option Default stepped Options Sets histogram curve style dialog The current working No directory is automatically changed to the displayed schematic when you switch schematic tabs Set this option to disable this feature Default false If true schematic and graph mouse cursors are modified to be suitable for use on a black background Default Full Options Possible values Partial dialog None and Full Affects progress information displayed during model library searching Chapter 13 Sundry Topics Name MaxVectorBufferSize MinGridHeight MinorGridPrintWidth MRUSize NewModelLifetime NoEditPinNamesWarning unsupported NolnitXaxisLimits No
101. to other applications such as word processors or drawing programs You can do this via the clipboard windows only see Copying to the Clipboard on page 78 or by writing out to a file To export schematic graphics to a file select the schematic menu File Save Picture then select the format of your choice using the Save as type drop down box The choices are l Windows Meta File EMF and WMF This is only available in Windows versions Nearly all windows applications that support graphics import will accept this format Note that this is a scalable format and therefore suitable for high resolution printing Chapter 4 Schematic Editor 2 Scalable Vector Graphics svg This is a relatively new format and is not supported by many applications However it is the only scalable format available in Linux 3 Bitmap default image size png jpg bmp These are available on all platforms are widely supported by graphics applications but these are not scalable formats and so do not offer good quality when printed using high resolution printers PNG is the default format if you do not choose a file extension and generally this is the format that provides the best image quality file size trade off To choose JPG JPEG format or BMP windows bitmap format you must explicitly enter jpg or bmp file extensions respectively With this option the image size will match the image size currently displayed on screen If you wish to spec
102. to search for it 2 Putin a separate file and pull in to the schematic with INC control see Simulator Reference Manual placed in simulator command F 11 window As 1 this will be read in unconditionally 3 Putin a library file and reference in schematic with LIB control see Simulator Reference Manual placed in simulator command F11 window Similar to 2 but more efficient if library has many models not used in the schematic Only the devices required will be read in 4 Put ina library file and install it using the procedure described in Full Model Installation Procedure on page 158 This will make the device globally available to all schematics You can also install it into the parts browser system These topics are covered in Device Library and Parts Management on page 157 and are also the subject of Tutorial 3 To place the device on the schematic find the symbol in schematic popup All Symbols and place in the normal way After it is placed select the device and press shift F7 and enter the subcircuit s name If you installed the device into the parts browser system as mentioned in choice 4 above you will be able to place the device by pressing control G and selecting the device from the appropriate category The parts browser system also provides a simple to use means of overcoming the problem mentioned above that occurs if the symbol s pin order does not match the subcircuit s node order This is explained
103. values 312 specifying the vertical value of the specified vector at the given x value Chapter 11 Command and Function Reference Function Reference Only a few of the approx 200 functions are documented here For the rest please refer to the Script Reference Manual This is available as a PDF file on the install CD A hardcopy version is also available for an additional charge The ones detailed here are the functions that accept and return numeric values and that could conceivably used for graph plots abs real complex Returns absolute value or magnitude of argument This function is identical to the mag function arg real complex Same as phase page 309 except the result wraps at 180 180 degrees arg_rad real complex Same as phase_rad page 309 except the result wraps at pi pi radians atan real complex Returns the arc tangent of its argument If degrees option is set return value is in degrees otherwise radians cos real complex Return cosine of argument in radians Use cos_deg if the argument is in degrees db real complex Returns 20 log10 mag argument diff real Returns the derivative of the argument with respect to its reference x values If the argument has no reference the function returns the derivative with respect to the argument s index in effect a vector containing the difference between successive values in the argument exp real complex Returns e raised to t
104. winding is strongly coupled to the secondary Such a transformer is likely to have a different coupling factor for the various windings You can use external leakage inductances to model coupling factor and this will provide some additional flexibility One approach is to set the user interface coupling factor to unity and model all non ideal coupling using external inductors In some cases it may be necessary to couple the leakage inductors Consider for example an E core with 4 windings one on each outer leg and two on the inner leg Each winding taken on its own would have approximately the same coupling to the core and so each would have the same leakage inductance But the two windings on the centre leg would be more closely coupled to each other than to the other windings To model this the leakage inductances for the centre windings could be coupled to each other using the mutual inductor method described in the next section Mutual Inductors You can specify coupling between any number of ideal inductors using the mutual inductor device There is no menu or schematic symbol for this It is defined by a line of text that must be added to the netlist See Manual Entry of Simulator Commands on page 65 The format for the mutual inductance line is Kxxxx inductor_1 inductor_2 coupling_factor Where inductor_1 Component reference of the first inductor to be coupled inductor_2 Component reference of the second inductor to be couple
105. you like including device power FFTs arbitrary expressions of simulation results and X Y plots such as Nyquist diagrams It is possible to set up fixed probes to plot arbitrary expressions of signals but this requires manually entering the underlying simulator command the GRAPH control There is no direct schematic support for this For details of the GRAPH control see the Command Reference chapter of the Simulator Reference Manual Fixed Probes There are several types of fixed probe Three of the commonly used probes are Chapter 3 Getting Started 1 Voltage Plots the voltage on a net 2 Current Plots the current in a device pin 3 Differential voltage Plots the voltage difference between two points They are simply schematic symbols with special properties When you place a fixed probe on the schematic the voltage or current at the point where you place the probe will be plotted each time you run the simulation The probes have a wide range of options which can be set by selecting the probe then pressing F7 These options are covered in detail in section Fixed Probes on page 214 There are more fixed probes available in addition to those described above See Fixed Probes on page 214 for details Fixed Voltage Probes You can place these on a schematic with the single hot key B or with one of the menus Probe Place Fixed Voltage Probe Place Probe Voltage Probe schematic popup Probe Voltage Hin
106. you update the license server to the latest flexlm version which is currently 9 5 Chapter 1 Introduction The files needed can be obtained from http www catena uk com Pages users html if you don t have the latest CD To update shutdown the license server then replace all the supplied files Once done the server may be restarted See Stopping and Starting the Service on page 21 for details for Windows You can find which version you are using with the Imutil utility Run lmutil lmver NEWTECH The result will be one of 7 0d 7 21 or 9 5 8 2a was also shipped specially to some users If the version you have is 7 0d then you must update as that version will not work with version 5 1 of SIMetrix If you are using 7 21 or 8 2a we recommend you update now as these versions will not function with future versions of SIMetrix Obtaining a License File Before we can issue you with a license file we need two pieces of information 1 The Ethernet address of the license server The Ethernet address is a 12 digit hexadecimal number and is associated with the Ethernet adapter in the server It is also known as the MAC address or sometimes the physical address 2 The computer hostname of the license server Please use the supplied utilities described below to find this information and not system utilities such as ifconfig and ipconfig The latter may return additional addresses that the license manager won t be able to see or
107. zoom level The font you select will be the size used for zoom magnification 1 0 as displayed in the status bar of the schematic Schematic used by bias annotation markers Schematic captions Popup menu Add Caption Schematic free text Popup menu Add Free Text Unassigned schematic fonts You can assign any of these fonts or in fact any of the other schematic fonts to any symbol property at the symbol definition stage You can also change the font assignment of any unprotected property on a schematic using the popup menu Edit Properties Window opened for viewing files such as the simulator list file or netlist file There are 8 fonts assigned for use on schematics This means that you can have up to eight different fonts on a schematic The actual definition of that font is defined in the Font dialog and stored with your user settings and is not stored in the schematic Only 349 User s Manual the name as in the list above is stored with the schematic property This means that if you give a schematic file to a colleague it may display differently on his machine depending on how the font options are set up So for this reason it is best to keep to the allocated purpose for each font Caption fonts should be large and possibly bold free text should be smaller etc etc Using a Black Background SIMetrix uses a white background for all its windows as is convention with GUI applications But it is possib
108. 0 eee eeeeeeeseeeeneeeenneeeeeeees 258 OVGIVIOW fica ones ein eee 258 Copy Data to the Clipboard ee eeeeeeeeeeeee 258 Copying Graphics to the Clipboard ee 258 Paste Data from the Clipboard 0 ee eeeeeeereeeees 259 Using the Internal Clipboard ee eeeeeeeeeeeeees 259 Exporting Graphics 0 0 0 eee eeeeeeeeeeeeeeeeeeeeeeeeeesaeeeeeneees 259 SAVING Graphs isiro oniiir 260 STIO EERTE ARTT 260 Restoring aeree er inae eea eaaa Saa EAEE 260 Viewing DC Operating Point Results eee 260 Schematic Annotation eener 260 Displaying Device Operating Point Info 2 10 261 List File Datas irinnorie tereny eit bets euaee 261 Other Methods of Obtaining Bias Data 0 261 Bias Annotation in SIMPLIS eee 261 Bias Annotation Display Precision ceeeee 261 Bias Annotation and Long Transient Runs 261 Saving Data iiio inea eied eie 262 Saving the Data of a Simulation eee 262 Restoring Simulation Data ee eeeseeeeeeeeeeee 262 Performance Analysis and Histograms 263 OVE VIEW siivosin ei EE cece bees cceped 263 EXAM Pl sce E attiacit doses E 263 Hist gr MS nssr er a ETa E 265 Goal Functions 0 0 ee eect cent eeeeeeeeeneeeeeneeeenaeeens 268 Data Import and Export eeceeeseeeeeeeeesneeeeenneeeeeeees 277 Importing SPICE3 Raw and CSDF Files 277 Importing Tabulated ASCII Data eee 277 Exporting SPICE3 Raw Files 278 Exporting Data Aisia i a en the 278 Launching
109. 1 gnd lt repeat idx NUM lt X idx idx idx 1 gnd section gt gt Chapter 4 Schematic Editor subckt section in out gnd R1 in out SRES C1 out gnd CAP S ends sends var_name in the above is set to idx If NUM were set to ten the line X idx idx idx 1 gnd section would be repeated 10 times with idx incrementing by one each time Note the semi colon at the end of the line This signifies that a new line must be created and is essential The end result of the above with NUM 10 RES 1k and CAP 1n is subckt ladder 1 11 gnd X1 1 2 gnd section X2 2 3 gnd section X3 3 4 gnd section X4 4 5 gnd section X5 5 6 gnd section X6 6 7 gnd section X7 7 8 gnd section X8 8 9 gnd section X9 9 10 gnd section X10 10 11 gnd section subckt section in out gnd Rl in out 1k C1 out gnd in ends ends Although it is legal to nest REPEAT keywords we recommend avoiding doing so as it can lead to unexpected results You can always use subcircuit definitions to each multi dimensional repeats and these are usually easier to understand The above example has multiple lines These can be entered using the Edit Properties dialog box The best way to define multiple line templates is to first enter them in a text editor and then copy and paste to the Edit Properties dialog SERIES lt SERIES num lt line gt gt Creates a series combination of the device described in line For example lt series series lt lt ref gt l
110. 116 Xspice pin attributes 97 toolbar editing 79 placement options 326 unselecting 73 in box 73 using for IC design 119 automatic area and perimeter calculation 120 window 70 worksheets adding and removing 79 zooming box 74 in 74 out 74 to fit 74 schematic_path property 105 SchematicEditMode option variable 340 SchematicExtension option variable 345 SchematicMoveMode option variable 340 SchematicReadOnly option variable 340 SchemDoubleClickScript option variable 340 ScriptDir option variable 322 340 ScriptExtension option variable 345 Scripts 282 location 329 options 330 startup 351 Scrolling graph 253 scterm property 105 Selecting schematic components and wires 71 Sensitivity analysis 191 sep template property keyword 110 series template property keyword 111 Set command 297 366 Index Settling time calculating 250 Show command 297 sign function 310 SimDataGroupDelete option variable 340 SIMPLIS Analysis modes AC 205 Periodic operating point POP 203 205 transient 201 analysis modes 201 options 205 primitive components 132 using SPICE models 127 SIMPLISComponentButtons option variable 341 SIMPLISPath option variable 341 Simulation modes 53 Simulator controls manual entry 65 Simulator options 192 simulator property 105 SIMXIDX n 166 sin function 310 Singular matrix 55 SnapshotExtension option variable 345 Snapshots SIMPLIS 203 sqrt function 310 STARTPATH system path 321 Startup script 351 START
111. 13 Chapter 3 Getting Started Setting Up a SIMPLIS Simulation SIMPLIS analyses are setup using the same menu as SIMetrix but you must first set the schematic to SIMPLIS mode See Simulation Modes SIMetrix or SIMPLIS on page 53 for details Select menu Simulator Choose Analysis You will see the following dialog box i E Choose SIMPLIS Analysis B Periodic Operating Point AC Transient Select analysis 5 aa C EOR Analysis parameters e Stop time 1m s O4 7 Transient rajo 4 Z Defaut Fi Save options All Plot data output al Voltages Only ci plotting o 3 Default O ata Probes Only e ee 1m al Default Number of plot 1k F Default points Lal sate C Eorce New Analysis J Ge Gee SIMPLIS has three analysis modes namely Transient Periodic Operating Point POP and AC Transient is similar to SIMetrix transient analysis POP is a unique analysis mode that finds the steady state of a switching circuit AC finds the small signal response of a periodic system Transient Analysis To setup a basic transient analysis 1 Check the Transient box in the Select analysis section 2 Enter an appropriate stop time under Analysis parameters 3 Enter an appropriate selection under Save Options Its usually best to select All This will instruct SIMPLIS to save all data for subsequent plotting In most cases the above is all you need to do For information on the remai
112. 2 is the second and so on Voltages are referred to by the label V Nn Again n identifies the actual voltage input in the same manner as for current In the example above the expression shown V n1 V n2 I V1 multiplies a voltage and current together This could be used to monitor the power in a two terminal device as shown in the following schematic v n1 V n2 1 V1 ARB2 YVI outp ARB2 OUTP M1 C Pulse 0 1 0 1m 1m k N4 OUTN N2 l In the above ARB2 is the device created from the Non linear Transfer Function menu ARB2 OUTP will carry a voltage equal to the power dissipation in R1 144 Chapter 5 Components Laplace Transfer Function Selecting the menu Place Analog Behavioural Laplace Transfer Function brings up the following dialog Define Laplace Transfer Function Ea Definition Define output using variable 1 s2 1 1 s 1 Frequency scale factor 6 28k Device Type Inout Outout Transfer function Single ended voltage Single ended voltage Single ended current O Single ended current Impedance Wl Differential voltage Differential voltage Admittance I V Differential current Differential current The operation of the various controls is described below Definition Enter an expression using the S variable to define the frequency domain transfer function The above shows the example of a s
113. 2 x1 as shown in the above diagram Note that data is assumed to be raw simulation data and may be complex It must not be in dBs Implemented by built in script uf_bandwidth See install CD for source CentreFreq CenterFreq CentreFreq data db_down See diagram in BPBW Bandwidth above Function returns x1 x2 2 Both British and North American spellings of centre center are accepted Implemented by built in script uf_centre_freq See install CD for source Duty Duty data threshold 271 User s Manual 272 First ve crossing Firgt ve crossing of threshold X2 f threshold X1 of threshgld X3 Function returns X2 X1 X3 X1 X1 X2 and X3 are defined in the above graph Default value for threshold is Ymax Ymin 2 Where Ymax largest value in data and Ymin in smallest value in data Implemented by built in script uf_duty See install CD for source Fall Fall data xStart xEnd A Y1 Amplitude V y2 Function returns the 10 to 90 fall time of the first falling edge that occurs between xl and x2 The 10 point is at y threshold Y1 Y2 Y1 0 1 and the 90 point is at y threshold Y1 Y2 Y1 0 9 If xStart is specified X1 xStart otherwise X1 x value of first point in data If xEnd is specified X2 xEnd otherwise X2 x value of last point in data If xStart is specified Y 1 y value at xStart otherwise Y1 maximum y value in data Chapter 9 Graphs Probes
114. 65 5 Graph results See Plotting Simulation Results on page 66 The following paragraphs briefly describe these steps More details are given in other sections Simulation Modes SiMetrix or SIMPLIS If you have SIMetrix SIMPLIS you can set the schematic editor to one of two modes to select whether you are using the SIMetrix native SPICE simulator or the SIMPLIS simulator To choose the simulator mode select the menu File Select Simulator then select which simulator you wish to use If the schematic is not empty and you change modes the program will check that all parts entered on the sheet are compatible with the newly selected simulation mode as not all parts will work in both modes Any that are believed not to be compatible will be highlighted and a warning will be issued To clear the highlighting select Edit Unhighlight You will most likely need to replace those components but in some cases you may simply need to re enter the same component If you wish to enter a circuit that will work in both modes you should enter it in SIMPLIS mode and not use any of the components in the menu Place SIMPLIS Primitives Following this advice will not guarantee a circuit with dual mode simulation ability but will minimise the chance of placing a device that is compatible with only one of the simulators Using the Schematic Editor Creating a Schematic The schematic editor has been designed to be intuitive to use and you may not ne
115. Add Curve 2 Select a value from the Available Vectors drop down box Transfer Function Vector Names The vector names for transfer function will be of the form source_name V gain source_name Transconductance source_name Transresistance source_name Igain where source_name is the name of a voltage or current source The vectors Zout Yout or Zin may also be available These represent output impedance output admittance and input impedance respectively For more information see the Command Reference chapter of the Simulator Reference Manual 221 User s Manual 222 Fourier Analysis A Fourier spectrum of a signal can be obtained in a number of ways You have a choice of using the default settings for the calculation of the Fourier spectrum or you can customise the settings for each plot The following menus use the default settings Probe Fourier Probe Voltage Quick Probe More Probe Functions Graph menu Measure Plot Fourier of Curve Graph menu Measure Plot Fourier of Curve Cursor span The following prompt you to customise the settings Probe Fourier Probe Voltage Custom Probe Fourier Arbitrary Command shell menu Graphs and Data Fourier Default Settings The default fourier spectrum settings are Setting Default value Method Interpolated FFT Number of points Next integral power of two larger than number of points in signal Interpolation order 2 Span All data except Measur
116. Analysis Dialog Note that the DC operating point is calculated automatically for all the other analysis modes described above although for noise analysis the results are not stored After a DC operating point has been completed you can annotate your schematic with markers to display the voltages at each node Press control M on the schematic to place a single marker or select the popup menu Bias Annotation Auto Place Markers to automatically place markers on all nodes See Viewing DC Operating Point Results on page 260 for full details Other Analysis Modes Real time noise An extension of transient analysis which enables noise generators for noisy devices using the same equations used for small signal noise analysis See Real Time Noise on page 187 Transfer function Similar to AC but instead of calculating the response to a usually single input it calculates the response from all signal sources to a single output See Transfer Function on page 188 Sensitivity Calculates the sensitivity of a specified output to device and model parameters See Sensitivity on page 191 Pole zero Calculates the poles and zeros of the circuit See Pole zero on page 191 Multi step Analyses Transient AC DC Noise and Transfer Function analyses can be run in an auto repeat mode while stepping a user defined parameter See Multi step Analyses on page 194 Monte Carlo Analysis See Monte Carlo Analysis on page 3
117. C Skip DC bias point Gear integration Fast start The simulation will run at Default higher speed but less precision up to this time Time Step The simulator always chooses the time step it uses but it will not rise above the maximum time step specified here If the simulator needs to use a time step smaller than the minimum specified the simulation will abort Reduce this value if the simulation aborts with the message Time step too small This might happen for long runs on circuits that have very small time constants Integration Method Set this to Gear if you see an unexplained triangular ringing in the simulation results Always use Trapezoidal for resonant circuits A full discussion on integration methods is given in the Convergence and Accuracy chapter of the Simulator Reference Manual Skip DC bias point If checked the simulation will start with all nodes at zero volts Note that unless all voltage and current sources are specified to have zero output at time zero the simulation may fail to converge if this option is specified Fast start The accuracy of the simulation will be relaxed for the period specified This will speed up the run at the expense of precision This is a means of accelerating the process of finding a steady state in circuits such as oscillators and switching power supplies Its often of little interest how the steady state is reached so precision can be relaxed while f
118. Device tolerances can be applied to the following components Capacitors Resistors Inductors Fixed voltage sources Fixed current sources Voltage controlled voltage sources Voltage controlled current sources Current controlled voltage sources Current controlled current sources Lossless transmission lines applied to ZO parameter Device tolerance will be ignored for other devices Model Tolerances Refer to Monte Carlo Analysis on page 237 of the Simulator Reference Manual Matching Devices Some devices such as resistor networks are constructed in a manner that their tolerances track Such devices often have two specifications one is an absolute tolerance and the other a matching tolerance A thin film resistor network might have an absolute tolerance of 1 but a matching tolerance of 0 05 This means that the resistors will vary over a 1 range but will always be within 0 05 of each other To specify matched devices for Monte Carlo analysis two pieces of information are required Firstly the components that are matched to each other must be identified and secondly their matching tolerances need to be specified To Identify Matched Devices 7 Select the components you wish to match to each other Use control key to select multiple components gt Select menu item Monte Carlo Match Selected Devices You must now supply a lot name which must be unique You can use any alphanumeric name Matchin
119. Disconnected Select items as described above Select schematic menu Edit Detach menu item Move items to desired location then press left mouse key You can rotate flip mirror the items see above while doing so To Move Property Text Labels To move a components value select then press control F7 To move the reference use control F8 To move any other property select device then popup Properties Move In general we recommend that you move the component to make text visible rather than the property text See Notes on Property Text Position on page 74 for more details To Duplicate Items Select items as described above Press the button on the toolbar ea Move the items to your desired location then press left key to fix You can rotate flip mirror the items see above while doing so Chapter 4 Schematic Editor To Copy Across Schematics Select block you wish to copy Choose menu Edit Copy In second schematic choose Edit Paste To Delete Select items as described above Press the cut button X on the toolbar or the delete key Multiple Selection Individual items which do not lie within a single rectangle can be selected by holding down the control key while using the mouse to select the desired items as described above Selecting Wires Only Hold down shift key while performing select operation Holding Down the ALT Key while selecting will limit component selection to only devices that are w
120. If this process fails the service will be marked for deletion and will actually be deleted when the machine is next re booted Starting the License Manager Manually It is not compulsory to run the license manager as a service It can be run as a normal application However it won t be started automatically when the machine is started and also required a user to be logged on To start the license manager manually open a command prompt window then CD to the directory where you copied the files Type at the command line lmgrd c lt license_path gt z If z is specified the server will run in the current command prompt window otherwise a new window will be opened 21 User s Manual 22 Installing Network Licensing for Linux Copying Files 1 Create a suitable directory on your machine for the FLEXIm files The following assumes usr local flexlm but you can use any location 2 Create target directory cd usr local mkdir flexlm cd flexlm 3 Copy the license manager files from the CD These are at cdrom Flexlm linux cp mnt cdrom linux Flexlm linux flexlm tar 4 Extract from tar ball tar xf flexlm tar 5 Copy the license file we have supplied to a suitable location You may choose to use the same directory as the FLEXIm files Starting Stopping License Manager The following assumes that you have installed the license manager to usr local flexlm and the license file is in the same directory To s
121. Keys Type Numeric Numeric Numeric Numeric Numeric Boolean Boolean Boolean Description User interface support Default 32768 See the Simulator Reference Manual for a full explanation Minimum allowed height of Options graph grid dialog Default 0 05 Options Print width in mm of dialog graph s minor grid Default 4 Options Number of items in dialog File Reopen menu Default 30 Number of days that user installed models remain displayed in the Recently Added Models parts browser category Default false If true the warning given when using the Edit Pin Names button in the associate models dialog box is inhibited Default false Inverse of default value of the initxlims parameter of the GRAPH statement See Simulator Reference Manual for details If on the default key Options definitions will be disabled dialog Note this will not take affect until the next session of SiMetrix 337 User s Manual 338 Name NoMenu NoStopOnError NoStopOnUnknownParam OldUserCatalog unsupported OmitAsciiRevision unsupported Openintro Type Boolean Boolean Boolean Text Boolean Boolean Description If on the default menu definitions will be disabled and no menu bar will appear This will not take affect until the next session of SIMetrix If disabled scripts and multi command lines i e several commands on the same line separated by
122. Line Segments Drawing straight line segments in the symbol editor is very similar to drawing wires in the schematic editor You can do one of the following 1 Select Draw Segment Mode by pressing the button You can now draw segments using the left and right mouse buttons Press the button again to revert to normal mode 2 Ifyou have a three button mouse the middle button will start a new segment The left button will complete a segment and terminate the operation while the right button will terminate without completing the current segment 3 Enter Draw Segment Mode temporarily by pressing F3 4 Double click the left button to start a new segment Drawing Arcs Circles and Ellipses The basic method of drawing each of the curved elements is the same for each case Before drawing starts you must define the start finish angle and for ellipses the ratio of height to width The drawing operation itself defines the start and finish points For full circles and ellipses the start and finish points are on opposite sides Chapter 4 Schematic Editor Dedicated menus are supplied for starting a full circle half circle and quarter circle For everything else use Arcs Ellipse Arc When you have initiated the operation the cursor will change to a shape showing a pencil with a small circle You can now draw the curved segment by dragging the mouse with the left key When you release the mouse button the operation will be complete and the
123. Model Library Re build Catalog File Format Catalog files are text files Each line provides data about a single device in semi colon delimited fields The fields are as follows Field 1 Field 2 Field 3 Device name as it appears in browser This may optionally be followed by a comma followed by the number of terminals for the model Symbol name Model property X for subcircuits as appropriate for other Chapter 6 Device Library and Parts Management devices This field is empty in ALL CAT and USER_V2 CAT it is determined automatically from electrical model when OUT CAT is built Field 4 Category Field 5 Sub category currently not used Field 6 Pin mapping order Filed 7 Path name duplicate device names only When you select OK your edits will be written to the USER_V2 CAT file see above table This is in the same format as ALL CAT in the root folder ALL CAT is never modified Also another file is updated called OUT CAT This is the file used by the parts browser The process of building OUT CAT may take a few seconds if the model library is large Importing Models to a Schematic SIMetrix provides a means to automatically import all models needed for a schematic into that schematic The models are placed in the simulator command window opened with F11 see Manual Entry of Simulator Commands on page 65 Once the models are imported to a schematic it will no longer be necessary for SIMetrix to locate the
124. Other Applications eeeeees 278 Data Files Text Format 279 Chapter 10 The Command Shell COMMA LING fe iieiea i a 281 Command History c cccceeeeceeceeeeseeeeeeeeeseeneeeees 281 Message WINdOW cccccecceeeeeeeeeeeeeteseeeeeeees 281 Multiple commands on one line eee eee eee eee 282 SClIPtS wv ere a ee saw sina Mamas 282 Command Line Editing 0 0 ee eeeeeeeeeeenneeeeeneees 282 User s Manual Chapter 11 Maximum Line Length 282 Command Line Switches ceeeeeeeeeeeeeeees 282 Editing the Menu System eee eeeeeeeesneeeeneeeneeeeees 282 OVGEIVIOW ninin louise esterases fesse 282 PROCCCUIG 2a 2 45 s2c2estanidesns cosestarctaxadbexextickereesetsseeiinns 283 Message WINdOW ccceeeseeeeeeeenteeeeeeeeetneeeeneeeeennaees 285 Menu Reference ccccceceeeeeeececeeeceeneeeesesesneaeeeeetees 285 Keyboard sida eed Mie ne heii 285 Command and Function Reference Command SUMMAN uu ce eeeceeceeeeeeeeeenteeeeeeeeeeneeeneaes 290 Referente eere canteen enra e a a ats 290 DefKey nai ceietectee neha ciaeuccenevinnessterigbicecmueinesemanenees 290 D IMGMU E EET ETE 292 DeIM NU iise nti ebisra is 294 OpenGroup ses deel Mee 294 ReadLogicCompatibility 0 cece eeeeeeeeeeeeeeee 295 ROSCt se irede tinen he Ed eden teed 296 DAVERNS ipod pe te ee ae eh dees 296 S nine ara i Mee 297 SOW A E A aathents 297 Uns ti nieun eiaei ie ES 298 F n
125. Point To specify a DC operating point analysis check DCOP Note that an operating point is performed automatically for all analysis modes and this is only useful if it is the only analysis specified Operating point analysis does not have any additional parameters so there is no tab sheet for it See Also OP in Simulator Reference Manual Viewing DC Operating Point Results on page 260 175 User s Manual Sweep Modes 176 Each of the analysis modes DC AC AC Noise and Transfer Function are swept That is they repeat a single analysis point while varying some circuit parameter There are 6 different sweep modes that can be applied to these analyses These modes are also used to define multi step analyses which are explained on page 194 The 6 modes are Device Temperature Parameter Model parameter Frequency not applicable to DC Monte Carlo As well as 6 different modes there are 3 different sweep methods Linear Decade List Dialog support for the List method is only available for the definition of Multi step analyses The simulator also offers an Octal sweep method but this is not supported by the Choose Analysis Dialog Not all combinations of sweep mode and analysis are available with all versions of the product Contact sales for details Each of the sweep modes is explained in more detail below Device Sweep In this mode the principal value of a single device is swept
126. Press a button or F12 or popup Zoom Out to zoom out one level Zoom In Press a button or shift F 12 or popup Zoom In to zoom in one level Panning Use the scroll bars to pan schematic You may also use the left right up and down cursor keys to pan the schematic one grid square in the relevant direction and the Page up Page down control left cursor control right cursor to pan the schematic 10 grid squares Also the schematic will auto pan if either of the left or right mouse keys is held down when the cursor enters the a region of the schematic less than one grid square from the window edge It is only possible to pan the schematic when scroll bars are visible Notes on Property Text Position The SIMetrix schematic editor has been designed using a basic principle that it is better to move the component to make its property text visible rather than move the property That way the component s value and other properties will always have a consistent location relative to the symbol body and there will be no confusion as to which component it belongs If you have a situation where some device label property text clashes with another your first thought will probably be to move the label We ask you instead to think about Chapter 4 Schematic Editor moving the component that owns the label it s nearly always a better way In situations where the label is very long it might be better to hide it altogether If you find that moving
127. S E E TEE E E E 93 Symbol Editor Window sses 93 The Elements of a Symbol esenee 94 Creating a New Symbol 94 Editing an Existing Symbol 94 Drawing Straight Line Segments eee 94 Drawing Arcs Circles and Ellipses 94 Placing and Defining Pins eeeseeeeeeeeeteeeeenees 95 Defining Properties eecceeeseeeeneeeseneeeesteeeeeaaes 97 Saving SyMDOIS ee cece cesneeeeeeeeeeeneeeeeneeseeeeees 100 Creating a Symbol from a Script 102 PrOpertleS nai E i AA 102 OVE IVIGW aicci vest eiior naiiai e aai 102 What is a Property nscsiscssciiciininnii iiini 103 Template Property Editing Properties in a Schematic 0 eee 106 Restoring Properties ce eeeeeeeceeesreeseneeeeeeeeeeees 106 User s Manual Chapter 5 Template Property cccs5 cccsseeseecesestiecesseeeseveeneeeneeveres 106 OVEIVIOW 0 0 ee cecececcee cece aces ceeeeeeaeeeeeecesacaeeeesnstnaeeeeess 106 Template Property Format ccecceeeeeeeeeees 107 Template Scripts 2 c 0 4 c eee eee 114 Symbol Library Manager eee ee eeceeeseeeeeeeeeeesnteeeeaes 114 Op ration Sii ecg siete ieee i en 115 Editing System Symbol Libraries 0 0 00 117 PSpice Schematics Translation 117 Configuring the Translator 117 If you don t have PSPiCe ee eeeeeeeeeeeeeneeeeeee 118 Reading PSpice Schematics 118 Installing PSpice Libraries for Use with SlMetrix 118 What the Translator will do cecseeeeeeeeee
128. SIMetrix SPICE and Mixed Mode Simulation User s Manual Copyright 1992 2006 Catena Software Ltd Trademarks PSpice is a trademark of Cadence Design Systems Inc Hspice is a trademark of Synopsis Inc Contact Catena Software Ltd Terence House 24 London Road Thatcham RG18 4LQ United Kingdom Tel 44 1635 866395 Fax 44 1635 868322 Email info catena uk com Internet http www catena uk com Copyright Catena Software Ltd 1992 2006 SIMetrix 5 3 User s Manual 10 11 06 Catena Software Ltd is a member of the Catena group of companies See http www catena nl Table of Contents Table of Contents Chapter1 Introduction Installation teisiin etaa a aeai 15 General Information ceeeeeeeeeeesneeeeeneeeeneeeeaas 15 Uninstalling vss chiniiin aai 15 A Note for System Administrators 0 0 eee 16 Installation LINUX Version 17 To Install frOM CD terririiegenrni 17 Installing to Other Locations 00 eeeeeeeteeeereees 17 Uninstalling Linux Version cceeeeeeeeeeeeeeeeee 18 L IGONSING seers sede aa r nays dtd Gated edeett es 18 OVEIVIOW 32 5 bi ee hat becca rate ee eA seeks 18 Installing Stand Alone License Files 005 18 Network Licensing Overview cceeeeeseeeeneees 19 Installing Network Licensing for Windows 20 Installing Network Licensing for Linux 22 Starting SlMetrix Network Version 22 Using TCP Potts iinne ariii 23 Changing t
129. Schematic F10 New graph sheet F11 Open close simulator command window schem F12 Zoom out schem Zoom in schem graph symbol graph symbol editor 287 User s Manual 288 Key Unshifted Shift Control Alt Insert Paste Copy Delete Delete Cut Home Zoom full graph Zoom full selected schem symbol axis graph End Page Up Page Down Up Scroll up schem graph Increment Big scroll component up schem potentiometer schem Scroll up selected axis graph Down Scroll down schem Decrement Big scroll graph component down potentiometer schem schem Scroll down selected axis graph Left Scroll left schem Scroll left selected Big scroll graph axis graph left schem Right Scroll right schem Scroll right Big scroll graph selected axis right graph schem SPACE TAB Step main cursor Step reference cursor ESC Abort macro cancel operation or pause simulation Chapter 11 Command and Function Reference Chapter 11 Command and Function Reference There are about 380 functions and 210 commands available but only a few are covered in this chapter Details of all available functions and commands can be found in the Script Reference Manual This is available as a PDF file on the install CD A hardcopy version is also available for an additional charge Notation Symbols Used Square brackets These signify a command line parameter or switch which is optional Pipe symbol This
130. Such signals or stimuli are specified using a voltage or current source which is placed on the schematic in the usual way A number of different types of source are available These are described in the following sections Waveform Generator This is used to create a time domain signal for transient analysis This generator will work in both SIMetrix and SIMPLIS modes of operation To place one of these devices select menu Place Sources Waveform Generator for a voltage source or Place Sources Current Waveform Generator for a current source To specify the signal for the source select then choose the popup menu Edit Part or press F7 This will bring up the dialog box shown below A Edit Waveform Dialog Time Frequency Wave shape S Period 1000 Frequency 10k s suas Wwidh 50u Duw 50 z O Triangle Rise 0 a Equal rise and fall O Sawtooth Fall 0 a Default rise and fall O Sine z Cosine Delay 0 Use delay Pulse Damping 0 z Use phase One pulse Vertical Dne pulse exp Initial 0 Offset 500m 4 O Step Pulse 1 Al Amplitude 1 Aj CO Off until delay Select the wave shape on the right hand side then enter the parameters as appropriate The following notes provide details on some of the controls Damping describes an exponential decay factor for sinusoidal wave shapes The decay is governed by the expression ETETE e damping t s Off until delay if checked specifies that the
131. TF tab as required 2 Define the analysis as required 3 In the Monte Carlo and Multi step Analysis section check the Enable multi step box then press the Define button This will open Define Multi Step Analysis Sweep mode Step parameters Device Start value 1k Parameter Stop value 2k 2 Model parameter Number of steps 10 3 Temperature Decade Group curves Frequency Linear Monte Carlo List Snapshot Define List Parameters Device name Cancel if Parameter name ag oO Uv E 4 In the Sweep mode section select Monte Carlo 5 In the Step Parameters section enter the number of steps required Running a Monte Carlo Analysis Monte Carlo analyses are run in exactly the same way as other analyses Press F9 or equivalent menu Setting the Seed Value The random variations are created using a pseudo random number sequence The sequence can be seeded such that it always produces the same sequence of numbers for a given seed In Monte Carlo analysis the random number generator is seeded with a new value at the start of each run and this seed value is displayed in the log file It is also possible to fix the first seed that is used using the SEED option This makes it possible to repeat a run To do this note the seed value of the run of interest from the log file then set the seed as follows 1 Select schematic menu Simulator Choose Analysis 318 Chapter 12 Monte Carl
132. UP INI 324 StartUpDir option variable 341 StartupDir option variable 322 StartUpFile option variable 341 StatusUpdatePeriod option variable 341 step template property keyword 112 Stimulus 56 Subcircuits 149 calling from a schematic 151 creating from schematic 149 expanding 194 passing parameters 152 SumNoise function 310 Sweep modes 176 180 367 User s Manual Switch voltage controlled 140 with hysteresis 141 Switches command line 282 Symbol editor 93 SymbolExtension option variable 345 Symbolic path names 321 Symbols see Schematic symbols SymbolsDir option variable 323 341 System requirements 29 T tan function 311 TempDataDir option variable 322 341 Temperature setting 193 sweeping 177 with multi step analysis 196 template property 105 106 TEMPPATH 321 TextExtension option variable 345 Timestep too small error 172 tol property 105 Tolerance current 193 relative 193 voltage 193 Toolbar graph 213 schematic 70 configure 79 TotalVectorBufferSize option variable 341 TranscriptErrors option variable 342 Transfer function analysis 188 plotting results 221 Transformer ideal 135 non linear 133 Transient analysis 170 175 SIMPLIS 201 Transient snapshots 173 Transmission line lossy 139 Truncate function 311 Tutorial 32 368 Index U IC 138 ndo Graph Zoom 254 ndoBufferSize option variable 342 ninstalling 15 nitvec function 311 nselecting schematic items 73 nset command 298
133. Unknown category but you can also edit the association of known devices in other categories Once the category has been selected a list of devices in that category will be displayed in the list box below You should then select a device or devices to associate To select multiple devices hold the control key down while selecting Note that you will not be allowed to select multiple devices that have different numbers of pins To help you determine what type of device it is its electrical model is displayed in the window that covers most of the lower half of the dialog box You must now define the Category symbol and if necessary the pin order for the device This is done using the top right hand group of controls titled Choose Symbol Category Select an appropriate category and symbol Note that only compatible symbols that have the same number of pins as the selected device will be shown If an appropriate symbol is not available you instruct SIMetrix to create one for you by pressing the Auto Create Symbol button The symbol created will be functionally correct but of course its design and labelling may not be exactly what you would like You can edit the pin names of the new symbol by pressing Edit Pin Names If other changes are required you can edit the symbol using the graphical symbol editor at a later time Chapter 6 Device Library and Parts Management The next list box allows the pin order to be changed If you used the auto
134. X server If you wish to use SIMetrix on such systems you must use a network license Network Licensing Overview SIMetrix uses the FLEXIm license manager from Macrovision Full end user documentation on this product can be found in docs flexlm all htm mnt cdrom docs flexIm all htm on the installation CDROM However most of what you will need to know to setup the system is contained within this chapter To use the license manager a license server must be installed and started on a single machine on your network The machine must be running Windows NT4 Windows 2000 or Windows XP and use TCP IP as its transport protocol No other windows versions are currently supported SIMetrix only products that is without SIMPLIS may also be licensed from a Linux machine even if the application itself is running on Windows 19 User s Manual 20 At the time of preparing this manual Windows Vista had not been finally released If you wish to run the license server on Windows Vista please contact technical support for information on whether this OS is supported Before you can use the license server you will need a license file which we will supply you The license file locks the server to a particular machine identified by its Host ID which is either an Ethernet ID or optionally the ID of a FLEXid dongle Before we can provide you with the license file we need to know the Host ID of your license server See Obtaining a License File on
135. a specifies the start time for switching instance data while Start plotting data specifies when PSP begins It is perfectly valid to set Analysis parameters gt Start saving data to zero so that all switching instance data is saved but to set Start plotting data to some later time Here is an example to illustrate why you might want to do this Suppose you are simulating a large circuit to 100mS but you are only interested in the last 20mS i e 80mS to 100mS You could set Start saving data to 80mS to reduce the amount of data generated and also to speed up the run However after the run is complete you look at the data and realise that you need to see what is happening from the start of the run As no data at all was output from the start the only thing to do is to rerun the entire simulation If instead however you had set Start plotting data to 80mS but left Start saving data at 0 SIMPLIS will have saved the switching instance data and only the PSP process will be needed to create the final plot data SIMPLIS is smart and is able to detect when you run the same simulation as before but with only changes to data output required So if you rerun the simulation with Start plotting data set to zero SIMPLIS will only perform the PSP which is very much quicker than the whole simulation This is the time at which the process of creating plot data is stopped i e when the PSP operation see above completes The total number of
136. a model within the MODEL control Again see the Simulator Reference Manual for details 200 Chapter 8 SIMPLIS Analysis Modes Chapter 8 SIMPLIS Analysis Modes Overview The SIMPLIS simulator is supplied with the SIMetrix SIMPLIS product For information on SIMPLIS see What is SIMPLIS on page 28 In this chapter we explain the analysis modes available with the SIMPLIS simulator There is more information on SIMPLIS analysis modes including full details of the netlist commands required to invoke them in the SIMPLIS Reference Manual To setup a SIMPLIS simulation you must first set the schematic editor to SIMPLIS mode See Simulation Modes SIMetrix or SIMPLIS on page 53 for details To set up a SIMPLIS analysis select menu Simulator Choose Analysis You will see this dialog box e Choose SIMPLIS Analysis CET Periodic Operating Point AC Transient Select analysis F pop Analysis parameters Ae Stop time 1m a p o y v Iransieni Start saving z E 0 Default data x Save options All Plot data output z ae RY Voltages Only sed se 0 s Default O Probes Only Stop plotting a data 1m j Default Number of plot a points 1k j Default C Eorce New Analysis SIMPLIS offers three analysis modes namely Transient AC and Periodic Operating Point or POP These analysis modes are described in detail in the SIMPLIS Reference Manual The meaning of each of the controls is described in this chapte
137. ace Connectors Small Terminal To specify the net name select the terminal then press F7 and enter your choice of name Hierarchical Schematic Entry 80 Schematics can be organised into multiple levels in a hierarchy Typically the top level would contain a number of blocks each of which represents an underlying child schematic Each of the child schematics can in turn contain more blocks You can create a hierarchical schematic in one of two ways Top down method Blocks are created first to make a functional diagram The underlying schematic for each block is created afterwards Bottom up method Schematics are designed first then blocks are created to use with them From version 4 1 the schematic and its symbol can be stored within the same file The combined element is known as a component and is usually given the file extension SXCMP In earlier versions the symbol or block had to be stored in the symbol library while the schematic was stored as a separate file This method is still supported but we recommend using the component method for all new designs All the methods for creating hierarchical schematics described in this section use components Top Down Method Creating Component Symbol Select schematic menu Hierarchy Create New Symbol This will open the graphical symbol editor See page 88 for details Note that the symbol you create must be given a Chapter 4 Schematic Editor Ref property typically with the
138. ace the components and wires as shown above The probe labelled Output can be selected from either Place Probe Voltage Probe or Probe Place Fixed Voltage Probe or just by pressing B in the schematic editor After placing the output probe select it then press F7 to edit its label Enter this in the box titled Curve Label All the other options may be left at their defaults For the pulse source V2 you can use Place Sources Universal Source or the Universal Source tool bar button Select V2 and press F7 Edit the settings as shown below Chapter 2 Quick Start in Choose Source Pulse Sine Noise ac DC Text Enable DC Time Frequency C Enable AC Period 5u 2 Frequency 200k a a Pulse Width 1 95u j Duw ad 3 ra i Sine Rise 50n m Equal rise and fall i Fal 50n a O Noise x C Default rise and fall 2 E t Delay 0 a O Tex None Repetitive Single Pulse O Step Vertical Initial 0 4 Offset 25 s Pulse 5 2 Amplitude 5 This sets up a 200kHz 5V pulse source with 40 duty cycle and 50nS rise time 6 Set up the simulation by selecting the schematic menu Simulator Choose Analysis In the dialog box check Transient Usually we would set the Stop time but on this occasion the default 1mS is actually what we want Now select the Advanced Options button In the Integration method box select Gear integration This improves the simulation res
139. adout text Properties Tab The properties tab lists all available properties of the CrosshairDimension object This will probably only be of interest if you are writing custom scripts to manipulate cursor dimensions More information on this subject can be found in the Script Reference Manual This is available as a PDF file on the install CD A hardcopy version is also available for an additional charge Status Bar Readout You can optionally have the cursor read out in the status bar instead of or as well as the on graph dimension display Select menu Cursors Display Options and select option as required This will change the current display You can opt to have this preference used as the default Select command shell menu File Options General then Graph Probe Data Analysis tab Select appropriate option in Cursor readout section Show Curve Info The menu Cursors Show Curve Info will display in the command shell information about the curve which currently has the main cursor attached The following information is listed Curve name Source group The name of the simulation group that was current when the Chapter 9 Graphs Probes and Data Analysis curve was created Curve id Only required when accessing curves using script commands Run number If there are multiple curves generated by a Monte Carlo run this is a number that identifies the run number that created the curve This number can be used to plot the curve alo
140. ain axis The main axis is the first axis that is created on a graph For example with the following graph E PsU Waveforms Selected Woe File Edit Cursors Annotate Curves Axes View Measure Plot 19 QQ Game EER SAE Re O 3P M IR5 P on tran I L3 P 1001 a i 350 300 250 lt 200 150 100 50 4 ee A Pe 0 9 08 0 7 06 05 0 4 0 3 02 o4 1 98 2 2 02 2 04 2 06 2 08 24 TimekSecs 20Secsidiv x 1 96009kKSecs y 48 02274 If you attempt to delete the selected axis the lower one nothing will happen Instead you should move the two curves in the top axis to the lower one See above section on how to move curves Editing Axes You can edit axis scales label and units by selecting the graph popup menu Edit Axis This brings up the following dialog box 238 Chapter 9 Graphs Probes and Data Analysis ES Edit Axis Lin O Log O Auto No change Auto scale Defined Min 1 9 Y Axis Lin O Log Auto No change Auto scale Defined Min 13 5192 Max 20 1841 The function of the Axis scales sheet and axis labels sheet is similar to the sheets of the same name in the define curve dialog box See Plotting an Arbitrary Expression on page 228 for details Reordering Grids and Digital Axes You can change the vertical order of the analog grids and
141. al SOUrCe cccceceecceeeeeeeeceeeeeeeeeeeeeeeees 57 Analysis Modes cccceeesceeeeneeeeereeeesneeeeeeeeeeeeeeeeenneeenaa 58 OVGEIVIEW oai eie a ee aed 58 Using the Choose Analysis Dialog eeeee 58 Setting Up a SIMPLIS Simulation 00 ee 63 Manual Entry of Simulator Commands 0 65 Running the Simulator eee eeeeeeeeeesneeeeeeeeeeneeeeeeas 65 SIM triX i al eevee ees 65 SIM PENS ves cetiee cast de acted ceeaah careaste tine E aa ria S aA 66 Plotting Simulation Results 66 OVE VIC W iota teh lbs teases Deane cath Dac gendaeeeed ate ewan tadhs 66 Fixed ProbeS i siccusicteedees anes oa es baked 66 Random Probes ccccccsecceeeeeeeeeeeeeeeseaeeeeeeeees 67 Schematic Editor Schematic Windows and Sheets eee 70 Schematic Editor WiIndOW 00 ce eeceeeeeeeeereeeeeeeeeee 70 Editing Operations 71 WINO 828 earebioe Sigetes Toon iG seta Nan Dsante aas 75 Edit Modes 0 aie ie eee aan 76 BUS COnMections 00 0 eee eeeeeeeeeeeeeeneeeeteeeesneeeeeaes 77 Copying to the Clipboard 78 Annotating a Schematic s 78 Assigning Component References 78 Checking the Schematic 00 0 0 ee eeeeeeeeeeeeeeneeeeeee 79 Schematic Preferences eereerereer 79 Adding and Removing Worksheets 79 Finding and Specifying Net Names 80 Hierarchical Schematic Entry s e 80 Top Down Method ssseeseeesseeesrriesrrirerrinrnenes 80 Bottom up method seeeeeiessresrrieerrieerren
142. all 500n S Default rise and fall t Delay 0 s Lw None Repetitive Single Pulse Step Vertical Initial 0 Offset 500m 3 Pulse 1 2 Amplitude 1 Pulse sine noise and DC waveforms may be specified using the tab sheets of the same name You can also specify a Piece wise linear source exponential source or a single frequency FM source To enter one of these select the Text tab and enter the appropriate syntax for the source Please refer to Voltage source in the Simulator Reference Manual for more information on these sources The AC sheet is for AC analysis only With the universal source you can specify transient AC and DC specifications simultaneously This is not possible with any of the other sources Analysis Modes 58 Overview In this section we explain how to setup the most commonly used analysis modes in both SIMetrix and SIMPLIS SIMetrix SIMPLIS product only For more comprehensive details on analysis modes see Analysis Modes on page 168 for SIMetrix and SIMPLIS Analysis Modes on page 201 for SIMPLIS Using the Choose Analysis Dialog Analysis mode is setup by selecting the menu Simulator Choose Analysis In SIMetrix mode this displays the following dialog box Chapter 3 Getting Started Pal Choose Analysis Be Transient AC DC Noise TF Options SOA CI Transient Transient parameters Dae Stop time Im ia CI DC Sweep C Noise Data output o
143. all signal frequency domain analysis mode applied to a switching circuit Please refer to the SIMPLIS Reference Manual for full details of this analysis mode Note that AC analysis requires a POP analysis see above to be also defined Setting up an AC Analysis 1 Select menu Simulator Choose Analysis 2 Select AC check box on the right Note that the POP check box is automatically checked when AC is checked 3 Select AC tab at the top Enter parameters as described in the following sections AC Sweep Parameters Start frequency Stop frequency Enter the start frequency for the AC sweep Enter the stop frequency for the AC sweep Points per decade Number of points Decade Linear SIMPLIS Options Save options All Voltages only Probes only Other Options Force New Analysis Ifa decade sweep is selected enter the number of points required for each decade If a linear sweep is selected enter the total number of points for the analysis Select type of sweep If selected all voltages and currents will be saved If selected only node voltages will be saved If selected only voltages and currents that are explicitly probed will be output This tells SIMPLIS to ignore any state information that it may have stored and which could be used to speed up the run For example any stored snapshots see above will not be used if this is selected 205 User s Manual Multi step and Monte Carlo Analyses 206
144. also a right click popup menu with the usual edit commands Maximum Line Length There is a maximum number of characters that can be entered on the command line but this is very large The limit is related to the number of words as well as characters and is typically in excess of 2000 words It is possible to exceed this limit with braced substitutions where the result of an expression is placed in the command line Note that lines larger than 512 characters will not be inserted into the command history The drop down list box attached to command line Command Line Switches Many commands have switches These are always preceded by a and their meaning is specific to the command There are however four global switches which can be applied to any command These must always be placed immediately after the command and before any command specific switches Global switches are as follows e Forces command text to copied to command history ne Inhibits command text copying to command history quiet Inhibits error messages for that command This only stops error message being displayed A script will still be aborted if an error occurs but no message will be output noerr Stops scripts being aborted if there is an error The error message will still be displayed Editing the Menu System 282 Overview The menu system in SIMetrix may be edited by one of two methods 1 Using the script language You can either edit the menu sxscr s
145. also be used to label resulting curves Persistence If non zero curves created from the curve will have a limited lifetime The persistence value is the number of curves from a single probe that will be displayed at once the oldest being automatically deleted If set to zero they will never be deleted Axis Type Specifies the type of y axis to use for the curve Auto Select Will use main y axis unless its unit are incompatible E g plotting a current but the graph already has a voltage In that case a new y axis will be created alongside the main one 215 User s Manual 216 Graph Analyses See diagram in section Graph Layout Multiple Y Axis Graphs on page 235 If the signal is digital a digital axis see below will be used for this probe Use Separate Y axis Will always use its own separate y axis If you specify this you can optionally supply an axis name The value of the axis name is arbitrary and is used to identify the axis so that multiple fixed probes can specify the same one This name is not used as a label for display purposes but simply as a means of identification Axes can be labelled using the Axis Labels sheet See below Use Separate Grid Similar to above but uses a new grid that is stacked on top of main grid See diagram in section Graph Layout Multiple Y Axis Graphs on page 235 Digital Use a digital axis Digital axes are placed at the top of the window and are stacked Each one
146. aluated as complex and only the final result is converted to real So 20 log data will be plotted as mag 20 log data This is not the same as 20 log mag data when data is complex mag real complex magnitude real complex Returns the magnitude of the argument This function is identical to the abs function maxidx real complex Returns index of the array element in argument 1 with the largest magnitude Maxima real real string Vector Minimum value Default v0 Options array Possible values are xSort Sort output in order of x values nolnterp Don t interpolate Returns an array of values holding every maximum point in the supplied vector whose value is above argument 2 The value returned if noJnterp is not specified is obtained by fitting a parabola to the maximum and each point either side then calculating the x y location of the point with zero slope If no nterp is specified the peak values are those found in argument 1 without any interpolation The vector returned by this function has an attached reference which contains the x values of the maximum points If xSort is not specified the vector is arranged in order of descending y values i e largest y value first smallest last Otherwise they are organised in ascending x values 307 User s Manual 308 Maximum real complex real real Vector Start x value End x value Returns the largest value found in the vector in the interval d
147. ame as DataGroupDelete see page 334 when simulator is run independently l e not called from the front end User interface support Options dialog Options dialog Options dialog Chapter 13 Sundry Topics Name Type Description User interface support SIMPLISComponentButtons Text As ComponentButtons but Schematic for SIMPLIS operation Toolbar menu SIMPLISPath Text Default EXEPATH sim No plis exe Path of SIMPLIS binary StartUpDir Text Current directory set at Options start of session dialog StartUpFile Text Default Startup SXSCR Options Script that is automatically dialog run at start of each session StatusUpdatePeriod Numeric Default 0 2 seconds No Minimum delay in seconds between updates of simulator status window during run SymbolsDir Text Default SHAREPATH Option SymbolLibs dialog Path of directory where system symbol libraries are located TempDataDir Text Default TEMPPATH Options SIMetrixTempData dialog See Default Configuration Location on page 324 for definition of TEMPPATH Directory where temporary simulation data files are placed TotalVectorBufferSize Numeric See the Simulator Reference Manual for a full explanation 341 User s Manual 342 Name Type Description User interface support TranscriptErrors Boolean Default false If true incorrectly typed commands will be entered in the history box The drop down list in the comman
148. ame as graph popup Zoom Full Recovering an Earlier Zoom 9 Press the Undo Zoom toolbar button to recover earlier zoom or scroll positions Scrolling with the Keyboard up down left and right cursor keys will scroll the active graph Zooming Selected Axes When using the mouse to zoom graphs all curves on the same grid are normally zoomed together To zoom only the curve on the selected grid press and hold the shift key while selecting the zoom area with the mouse Notes If you add a new curve to a graph which has been zoomed the axes limits will not change to accommodate that curve if the new curve does not lie within the zoomed area you will not see it Selecting graph popup Zoom Full or pressing HOME key restores the graph to auto scaling and the limits will always adjust so that all curves are visible even ones subsequently added Zoom to Fit Y axis To zoom in the y axis only to fit the displayed x axis press the Fit Height toolbar A button Annotating a Graph 254 A number of objects are available to annotate graphs for documentation purposes These are Curve Marker A single arrow line and item of text to identify a curve or feature of a curve 5 Legend Box Box of text that lists all the names of curves currently displayed Text Box Box containing text message S Free Text Similar to text box but without border and background Caption As free text but designed for single line heading Cu
149. an expression See the Monte Carlo Analysis chapter of the Simulator Reference Manual for details Running Monte Carlo Overview There are actually two types of Monte Carlo analyses These are 1 Single step Monte Carlo sweep 2 Multi step Monte Carlo run 1 above is applicable to AC DC Noise and Transfer Function analyses 2 can be applied to the same analyses in addition to transient analysis An example of 1 can be seen on page 179 This was a run where the gain at a single frequency was calculated 1000 times with the Monte Carlo tolerances applied This used AC analysis with the Monte Carlo sweep mode one of the six modes available Only a single curve is created hence the name single step An example of 2 is the example at the beginning of this chapter Here a complete frequency sweep from 1kHz to 100kHz was repeated 100 times creating 100 curves Setting up a Single Step Monte Carlo Sweep l Select schematic menu Simulator Choose Analysis Select the AC DC Noise or TF tab as required 2 Inthe Sweep Parameters section press the Define button 3 In the Sweep Mode section select Monte Carlo 317 User s Manual 4 In the Parameters section enter the required value for the Number of points 5 For AC Noise and TF you must also supply a value for Frequency Setting up a Multi Step Monte Carlo Run 1 Select schematic menu Simulator Choose Analysis Select the AC DC Noise Transient or
150. and phase Bus plot Plots bus signal in logic Menu Probe Place Fixed analyser style Bus Probe These probes are simply schematic symbols with special properties When you place a fixed probe on the schematic the probed value at the point where you place the probe will be plotted each time you run the simulation 214 Chapter 9 Graphs Probes and Data Analysis Current probes must be placed directly over a component pin They will have no function if they are not and a warning message will be displayed Fixed Voltage and Current Probe Options These probe types have a large number of options allowing you to customise how you want the graph plotted For many applications the default settings are satisfactory In this section the full details of available probe options are described Select the probe and press F7 or menu Edit Part The following dialog will be displayed PS Edit Probe Probe Options Axis Scales Axis Labels Curve label Persistence a V1 pos 0 3 Axis type Graph Auto select C Use separate graph Use separate Y axis Graph name Use separate grid Ariens Digital Transient Axis name DC Sweep Display order digital curves AC sweep Arbitrary string to specify order Colour Use default Edit C Plot on completion only The elements of each tabbed sheet are explained below Probe Options Sheet Curve Label Text that will be displayed by the probe on the schematic and will
151. any primitive model or subcircuit In this method the SPICE device is measured using the SIMetrix simulator in a number of test circuits The results of these tests are then analysed and used to derive the final SIMPLIS model SPICE to SIMPLIS conversion takes place when you place the device on the schematic If Simulated parameter extraction is being used the message Extracting SIMPLIS model for Please wait will be displayed For MOSFETs this process usually takes less than about 0 5 seconds on a 1 5G P4 machine but can be much longer Note that Simulated parameter extraction is not guaranteed to succeed and can fail if the SPICE model is faulty or badly designed Additional Parameters Semiconductor devices converted for SIMPLIS operation have some additional parameters that may be edited after the device is placed This is done using the popup menu Edit Additional Parameters In general each device has two types of additional parameter These are LEVEL parameters which define the complexity of the model 127 User s Manual 128 used and LIMIT parameters which define operating limits for the device The latter are used to work out suitable coordinates for the piece wise linear approximation needed for SIMPLIS devices Model complexity defined by LEVEL parameters trade off accuracy for speed The following table explains the meaning of the parameters for each device Device Parameters Diodes Maximum current This
152. apter 3 Getting Started 1 Select AC sheet 2 Check the AC box under Select analysis 3 Enter parameters in Sweep Parameters section These have the same meaning as the equivalent SIMetrix analysis Manual Entry of Simulator Commands The analysis mode selected using Simulator Choose Analysis is stored in text form in the schematic s simulator command window If you wish it is possible to edit this directly Users familiar with the simulator s syntax may prefer this approach Note that the text entered in the simulator command window and the Choose Analysis dialog box settings remain synchronised so you can freely switch between the two methods To open the simulator command window select the schematic then press the F11 key It has a toggle action pressing it again will hide it If you have already selected an analysis mode using the Choose Analysis dialog box you will see the simulator controls already present The window has a popup menu selected with the right key The last item Edit file at cursor will open a text editor with the file name pointed to by the cursor or selected text item if there is one The simulator command window can be resized using the splitter bar between it and the schematic drawing area If you have SIMetrix SIMPLIS you should use the SIMULATOR control to mark SIMetrix and SIMPLIS entries If SIMULATOR SIMetrix is encountered all following lines will only work in SIMetrix mode and will be ignored b
153. arranges pin order This is a sequence of numbers each representing a symbol pin order The order of the numbers in the mapping is the order in which the schematic symbol pins placed on the netlist For example the LMC6762B comparator in the library is assigned a mapping of 1 2 5 3 4 The output on the comparator symbol is pin 5 but the model requires this to be the third node in the netlist entry Additional parameters for device appended to value If model property is X the keyword params prefixes the params property value Specifies a customised netlist entry for the device See Template Property on page 105 below for full details Specifies a script to be called when F7 or equivalent menu is selected Script to be called when the shift up key is pressed This is to increment a component s value Currently used for potentiometers and some passive devices As incscript but for shift down to decrement a device This property is automatically allocated to every instance and always has a unique value Because it is automatically added it is the only property that every schematic component is guaranteed to possess This property is protected and therefore cannot be edited Determines simulator compatibility See Properties You Need to Add on page 91 Template Property This is the subject of its own section See below 105 User s Manual Editing Properties in a Schematic Unprotected properties of a symbol pla
154. as Nyquist diagrams It is possible to set up fixed probes to plot arbitrary expressions of signals but this requires manually entering the underlying simulator command the GRAPH control There is no direct schematic support for this For more info on the GRAPH control see the Command Reference Chapter of the Simulator Reference Manual Fixed Probes There are 8 types of fixed probe as described in the following table Probe Type Description To Place Voltage Single ended voltage Hint If Menu Probe Place Fixed you place the probe Voltage Probe immediately on an existing schematic wire it will Hot key B automatically be given a meaningful name related to what it is connected to Current Device pin current A single Menu Probe Place Fixed terminal device to place over Current Probe a device pin Hot key U Inline current In line current This isa two Menu Probe Place Inline terminal device that probes Current Probe the current flowing through it Differential voltage Probe voltage between two Menu Probe Place Fixed points Diff Voltage Probe dB Probes db value of signal Menu Probe AC voltage Only useful in AC Noise Fixed dB Probe analysis Phase Probes phase of signal Menu Probe AC voltage Only useful in AC Noise Fixed phase Probe analysis Bode plot Plots db and phase of vout Menu Probe AC vin Connect to the input and Noise Bode Plot Probe output of a circuit to plot its gain
155. at for toolbar symbols onl Most Recent Files component Siner ch uf 15 4 C Defaut ebadedls tes Edit Mode Bias nnotation Precision O Classic 6 a Default Grow wire Enable smart wiring aM oO See Help for info Ml Wiring 3 Allow route through connected Grid Orthogonal M C Hide grid Schematic Sheet Undo Level Number of levels of schematic undo See Creating a Schematic on page 53 Placement When to auto repeat placement of schematic components If auto repeat is enabled a new symbol to be placed is automatically displayed after each placement This speeds the placement of many instances of the same device Most Recent Files Controls how many recently used files are displayed in the File Reopen menu Double click mode Selects action when double clicking a schematic instance Select Classic to retain pre version 5 0 behaviour whereby double clicking always starts a new wire Select Edit selected component for the default behaviour which is to invoke the device value editor Bias Annotation Precision Controls the precision of the schematic voltage and current bias annotation markers Grid Option to hide the schematic s grid Wiring Enable smart wiring enable the smart wiring algorithm See Wiring on page 75 for details about smart wiring 326 Double click mode Edit Mode Graph Printing Axis line width Grid line width Curve line width Curve identification Chapter
156. atch to within 0 2 The absolute tolerance is the lot tolerance This is how it can be implemented 1 Assign a random variable using the VAR preprocessor control You cannot use PARAM in SIMPLIS simulations E g VAR rvl UNIF 0 02 2 Give each resistor in the network a value of 1K rvl UNIF 0 002 rv will be updated on each Monte Carlo step but will always have the same value in each place where it is used Performance Analysis and Histograms Once a SIMPLIS multi step or Monte Carlo analysis is complete the data can be analysed in exactly the same way as for SIMetrix multi step analyses This includes the performance analysis and histogram features For more information see Performance Analysis and Histograms on page 263 Condition Back annotation Overview On each run SIMPLIS generates a file called the initial condition file This contains a sequence of SIMPLIS netlist commands that initialises a circuit to the state achieved at the end of the run This allows a new run to continue from where a previous run completed The initial condition file can be applied by including it in the netlist for a new run and in some instances this may be the most convenient method However it is also possible to annotate the schematic with the initial condition information This has some advantages 1 The initial conditions back annotated to top level capacitors and inductors will also be recognised in SIM
157. atic Windows and Sheets To Open a new schematic window select menu File New Schematic Window To Open a new schematic sheet select menu File New Schematic Sheet This will create a new sheet in the selected window If no schematic is open one will be created Selecting Simulator Mode If you have SIMetrix SIMPLIS and you wish to enter a schematic for simulation with SIMPLIS you should select SIMPLIS simulator mode To do this select menu File Select Simulator then select SIMPLIS Schematic Editor Window Cut File Operations Undo Duplicate Rotate Mirror Flip Zoom box outlin Select wiring mode Place components untitled a aN Ee Edt View Simulator paca Probe Eros Aeiio Hierarchy ee ae o ra yi 7 ae Sane A SHE HXCHEG AQ Zeit EEXeO unnamed ara Edit Part F7 Edit A P Ctrl Alt F tide show Value Descend Hierarct Ctrl E L Probe Voltage F4 elect gt C 1 Probe Current Display Device Bias Infc E Edit Propert Delete Proper Function of left Be ton Relative zoom level ge Move Text 70 Popup menu open using right mouse click Chapter 4 Schematic Editor Editing Operations To Place a Component If it is a simple device which only needs a value such as a resistor or capacitor select the appropriate symbol from the tool bar or Parts menu For other devices that require a part number it is easiest to use the parts browser Select menu
158. automatic path matching algorithm attempts to match a user symbol or one of the EXEPATH or DOCSPATH system symbols to a part of the path being processed If a match is found the path name will be stored with the symbolic value Component paths If a component is placed using the full path option the automatic path matching mechanism described above will be invoked For example suppose the user symbol CELLS has the value C Projects Proj1 Cells and the component with path C Projects Proj1 Cells celllib1 inv sxsch is placed using the full path method The actual value of the schematic_path property will become CELLS celllib l inv sxsch The matching of C Projects Proj1 Cells to CELLS is performed automatically Note that automatic path matching will not be invoked for components placed using the relative path method Global model library file paths Model files installed globally can use symbolic paths The automatic path matching mechanism described above will be invoked when models are installed So if the model file C SPICELIB OnSemi mod and the symbol MODELLIB has the value C SPICELIB the model file path will be saved as MODELLIB OnSemi mod Path option variables StartupDir ScriptDir BiScriptDir TempDataDir Chapter 13 Sundry Topics PSpiceIniPath DefaultLib SymbolsDir Automatic path matching is invoked whenever these values are set or modified Symbol file locations Schematic symbol file paths may be
159. automatically resolves to the curve s label If the curve name is edited with menu Curves Rename curve this value will reflect the change You can of course enter any text in this box You can also use expressions in the same manner as for cursor dimensions See Label on page 245 Text Alignment This is how the label is aligned to the arrowed line If set to automatic the alignment will be chosen to be the most appropriate for the relative position of the label and the arrowhead Uncheck automatic and select from the list to fix at a particular alignment 255 User s Manual 256 Font Press Edit Font to change font for text Other Properties Snap To Curve You can switch off the action that causes curve markers to always snap to a curve Select Properties tab then double click on SnapToCurve item Select Off You will now be able to move the curve marker to any location Legend Box Placing Select menu Annotate Add Legend Box A box listing all the curve names will appear at the top left of the graph Moving Place cursor inside the box and drag to new location Resizing You can alter the maximum height of the box by placing the mouse cursor on it s bottom edge and dragging The text in the box will automatically reposition to comply with the new maximum height Editing Properties Double click on the box or select then menu Annotate Edit Selected Object The following dialog will be opened e Edit Legend B
160. aved when you open that schematic it has a choice between its local copy of the symbol or the copy in the library Which it chooses depends on an option chosen when the symbol is saved When saving the symbol with the graphical editor you will see the check box All references to symbols automatically updated If this is checked then the schematic editor will always use the library symbol if present If not it will use its local copy If a schematic is using a local copy and you wish to update it to the current library version select the symbol or symbols then select the popup menu Update Symbol Note that all instances of the symbol will be updated It is not possible to have two versions of a symbol on the same schematic 121 User s Manual 122 Important Note Note that only the symbol geometry pin definitions and protected properties of a schematic instance will be changed when its symbol definition is edited Unprotected properties will remain as they are For example the standard NPN bipolar transistor symbol has an initial value property of Q2N2222 so when you place one of these on the schematic from the Place menu or tool bar this is the value first displayed This can of course be subsequently changed The initial value of Q2N2222 is defined in the NPN symbol However if you edit the symbol definition and change the initial value to something else say BC547 the value of the value property for any instances of that s
161. aving to pass the connection by connecting a terminal symbol Place Connectors Terminal and then assigning it the name VCC Global Pins Supposing you have two instances of a hierarchical block which you wish to connect to different supply rails To do this you would need to connect the supplies say VCC to pins at the top level with explicit i e non global connections at the lower levels So every child schematic at lower levels would also need VCC pins However it is sometime convenient to hide these connections When there is only one supply for an entire design this can be done using global nets However in the scenario we described above there are two versions of VCC so we would not be able to use a global net in this case A solution to this is to use a feature of SIMetrix called Global Pins Global pins are defined during symbol definition Once a pin is defined as global a net of the same name will be available in all child schematics at all levels without the need for it to be explicitly passed Example 5 12 oy oO block1 sxsch block1 sxsch vec U1 vec U2 b In Out In Out VEE VEE Sine 0 1 1k 0 0 k Jv 1K 1K R1 R2 12 cy Top level schematic 1K Pr i block2 sxsch PinBin1 a e Block 1 Chapter 4 Schematic Editor p at Pind B FVN Pin1 VEE Block 2 In the above example VCC and VEE connections have been
162. ay further from the main lobe Hamming starts smaller but doesn t decay whereas Hanning while starting off larger than Hamming decays as the frequency moves away from the central lobe Despite the great deal of research that has been completed on window functions for many applications the difference between Hanning Hamming and Blackman is not important and usually Hanning is a good compromise There are situations where a rectangular window can give significantly superior results This requires that the fundamental frequency is specified and also that the simulated signal is consistent over a large number of cycles The rectangular window however usually gives considerably poorer results and must be used with caution Probing Busses It is possible to probe a bus as long as all the signals on the bus are digital In this case a plot representing all the signals on the bus will be created Usually this will be a numeric display of the digital bus data but it is also possible to display the data as an analog waveform Chapter 9 Graphs Probes and Data Analysis To probe bus using default settings Use the schematic popup menu Probe Voltage or hot key F4 and probe the bus in the same way as you would a single wire This will plot a numeric trace using decimal values To probe bus using custom settings 1 Select menu Probe Voltage Bus 2 Click on desired bus 3 Enter the desired bus parameters as described in Bus Probe O
163. bol on your schematic To Draw Busses There is no special method of drawing busses Simply wire up bus rippers as you would any other component As soon as you connect to the bus pin of a bus ripper the colour and thickness of the wire will automatically change to signify that it is a bus 77 User s Manual 78 To Increase Reduce the Connections to a Bus If you wish to add connections to or delete connections from a bus ripper select the ripper device and press F7 or popup menu Edit Part The same dialog as above will be displayed Adjust the start and end indexes appropriately then close the box Connecting Busses in a Hierarchy See Connecting Busses in a Hierarchy on page 83 Copying to the Clipboard To copy schematics to the clipboard select the entire schematic then choose menu Edit Copy If you wish the schematic to be copied in black white select Edit Copy Monochromatic It is recommended that you zoom the schematic to fill the window prior to copying to the clipboard After copying to the clipboard the schematic can be pasted into another application such as a word processor Annotating a Schematic You can add a caption or free text to a schematic The only difference between them is the font style and justification Captions use a heavy font and are centre justified Free text use a smaller font and are left justified To place a caption or free text use the popup or fixed menus Edit Add Caption or
164. box similar to that shown above will be displayed but with the Available Libraries box empty Select the devices you wish to remove from the Selected Libraries box Parts Management Advanced Topics Associating Multiple Models with Symbols The procedure for installing model libraries above Full Model Installation Procedure on page 158 explains how to install the library and then if required associate each model individually as you place the device on the schematic In some situations you might wish to perform the association process in bulk that is for many devices at once To so this use the File Model Library Associate Models and Symbols menu This is what you will see 161 User s Manual 162 fal Associate Models and Symbols Select Devices Choose Category mm Unknown M Unassigned im Define Symbol ADS587 Auto Create Symbol Pin order 4 EJ E Edit Pin Names Electrical Model SXOA1000 From C Program Files SIMetrixS3 examples Tutorial3 mod line 14 a Opamp SR Negative SUP este Sh GIRS EU cout bef Inverting input Non inv input al Apply Changes Cancel Help Associate Model dialog box In the top left hand group you select the device or devices that you wish to associate The drop down box at the top has a list of categories Usually you would select a device or devices in the
165. ced on a schematic may be edited using the popup menu Edit Properties This first opens a dialog listing all properties owned by the device After selecting the property to edit a dialog box similar to the box described in Defining Properties on page 97 If the property you select is protected the dialog box will still open but you will not be able to change any of the settings Restoring Properties This is a method of restoring an instance s properties to the values and attributes of the original symbol This is especially useful in situations where a symbol has been edited to say add a new property and you wish that new property to be included on existing instances of that symbol To restore instances properties follow the instructions below 1 Select the instances whose properties you wish to restore 2 Select popup menu Restore Properties 3 There are two options New Properties Only will only add new properties to the selected instances That is any property that is present on the symbol definition but not on the schematic instance of it will be added All other properties will remain intact All Properties will restore all properties to that of the symbol definition This includes deleting any instance properties that are not in the symbol definition In effect this will restore the symbol as if it had just been placed using the Place From Symbol Library menu Note that REF properties will be automatically annotated
166. cellaneous sxslb tmixed_mode sxslb passives sxslb semiconductors sxslb sheet_text sxsib simplis sxslb create NPN cascode f sources sxsib Goa NPN darlington analog sxslb y NPN dual NPN dual 4 term current mirror JA NPN quad no substrate NPN quad with substrate PNP schottky aff PNP 3 terminal a PNP 4 terminal b TE PNP darlington p Delete Copy Create eetere ce j Internal name npn Edit Place Note that the box can be resized in the usual way The symbols available to the schematic editor are stored in library files which conventionally have the extension SXSLB Only symbols in installed libraries are available for placing a new part Note however that once a symbol is placed on a schematic a copy is stored locally so you can still view a schematic that uses symbols that are not installed The symbols in each file are grouped into categories using a tree structure as shown above in the Symbols box The manager allows you to install or uninstall library files to move symbols between files or categories to delete symbols to copy symbols and to create new categories You can also create new empty symbols ready for editing with the symbol editor Operations Installing Libraries Select the Add button and select a library file to install Note that if you have the PSpice translator option you can install PSpice symbol libra
167. cessarily perfect results in a wide range of cases To increase accuracy in the case described above start the analysis at a lower frequency this will lower the frequency at which the OdB reference is taken Plots from curves Two plots can be made directly from selected curves These are described below FFT of Selected Curve With a single curve selected from legend popup menu select Plot FFT of Selected Curve A new graph sheet will be opened with the FFT of the curve displayed To plot an FFT of the curve over the span defined by the cursor locations select Plot FFT of Selected Curve Cursor span Smoothed Curves With a single curve selected from legend popup menu select More Functions then under the Plot branch select LP Filter and choose a time constant Press OK and a new curve will be displayed showing a smoothed version of the original curve This system uses a first order digital IIR filter to perform the filtering action Graph Zooming and Scrolling Zooming with the Mouse To zoom in on a portion of a graph place the cursor at the top left of the area you wish to view press and hold the left mouse key then move cursor to bottom right of area and release left key The axes limits will be modified appropriately To view whole graph again select the graph popup Zoom Full or toolbar button Zooming with the Keyboard 253 User s Manual F12 to zoom out shift F12 to zoom in HOME returns graph to full view S
168. chematic is shown below Chapter 2 Quick Start Amolifier Output To make this modification proceed as follows 1 3 Press the Resistor button in the component toolbar Alternatively select the menu Place Passives Resistor Box shape or if you prefer Place Passives Resistor Z shape A resistor symbol will appear Place this in the location shown in the diagram above Click the left mouse button to fix it to the schematic You may now see another resistor symbol appear depending on how the system options are set Cancel this by clicking the right mouse button Now wire up the resistor There are a number of ways of doing this If you have a three button mouse or wheel mouse the easiest is to use the middle button or wheel Pressing it once will start a wire Pressing it again will fix it and start a new one Pressing the right button will terminate it If you have a two button mouse you can start wiring by pressing F3 followed by a left click or double clicking the left button A left click will now finish a wire a start a new one Right click will complete wiring operation You can also enter wiring mode by selecting the toolbar wire button 2 This puts schematic into a permanent wiring mode where the left key is always used for wiring Revert to normal mode by pressing the wire button again Re run the simulation by pressing F9 The graph will now be updated to 35 User s Manual Amplifier Outp
169. ck pins to schematic module ports If you are creating a symbol to use with an existing subcircuit from say a model library the netlist order must match the order in which the pins are defined for the subcircuit definition Symbol Pin Order The up down arrow keys allow you to modify the symbol pin order This is the relative position on the symbol that the pins will appear Pins higher up the list will appear higher on the symbol if defined as left or right or to the left if defined as top or bottom Modifying Pins 1 Select pin in list box 2 Change the characteristic you wish to modify Note that SIMetrix will not allow you to change the netlist order to a value that is already used 3 Press Modify Properties Properties defined for a symbol are actually the initial properties present when the symbol is first placed on a schematic These can be changed afterwards 1 To edit properties proceed as follows 2 Press Properties Tab The following will be displayed 90 Chapter 4 Schematic Editor A Symbol Definition x Name Catalog Style Pin Definition Properties Define property Name Location Initial Auto Right value Right C Protected O Eixed Visible Manage properties Value Value Auto right right Add Ref U Auto right right Model x Hidden Modify Delete Current Symbol New Symbol CESS 3 All schematic symbols must have a component reference ref prope
170. coupled Full RMS AC coupled Per Cycle RMS AC coupled Cursor span Mean Full Mean Per Cycle Mean Cursor span Peak Full Peak Cursor span Trough Full Trough Cursor span Peak Peak Full Peak Peak Cursor span Rise Time First edge 10 90 Access from menu RMS menu More Functions Toolbar menu RMS cycle menu More Functions menu More Functions menu More Functions menu More Functions menu More Functions menu Mean menu More Functions Toolbar menu Mean cycle menu More Functions menu More Functions menu Peak menu More Functions menu More Functions menu Trough menu More Functions menu More Functions menu More Functions menu More Functions Toolbar menu Rise Time menu More Functions Description RMS for full span RMS for each cycle RMS over span defined by cursor positions RMS of AC component only for full span RMS of AC component only for each cycle RMS of AC component only over span defined by cursor positions Mean for full span Mean for each cycle Mean over span defined by cursor positions Magnitude and location of peak for full span Magnitude and location of peak over span defined by cursor positions Magnitude and location of trough for full span Magnitude and location of trough over span defined by cursor positions Peak peak for f
171. create symbol described in the above paragraph you will not need to change the pin order Even if you used an existing symbol from the drop down box you probably won t need to change the default as most devices such as opamps and MOSFETs use a de facto standard pin order Usually you can check the pin order from the Electrical Model display at the bottom of the dialog box Many subcircuit definitions are preceded by text which identifies each connection to the sub circuit This must correspond exactly to the pin order of the symbol The names of symbol pins and the names used for the subcircuit terminations do not need to match only the order is important If the pin order does not match you can change it using the up and down arrow buttons Simply select a pin in the list box then move it up or down the list Note that the change will only apply to the device s you are currently editing other devices associated with the same symbol will be unaffected Once you have finished selecting the category symbol and pin mapping you must select the Apply Changes button Your edits will be lost if you don t but you will be warned about this before closing the box Embedded Association It is possible to embed association information within the model file itself This is useful if you wish to prepare a model to distribute to other users and wish to spare them the burden of performing the association process themselves Models with embedded association ca
172. cript that builds the menu system on program start or you can make additions by adding commands to the start up script Chapter 10 The Command Shell 2 Using the GUI based menu editor The first method offers the ultimate in flexibility but has a steep learning curve The second method is quite simple to use and is appropriate for simple changes to the menu system such as deleting unused menus or changing hot key definitions The following describes the second method For details about the first method please refer to the Script Reference Manual Procedure Select menu File Options Edit Menu This will open the following dialog box ite Edit Menu System TI Menu Name Accelerator Schematic SIMPLIS View Schematic Popup SIMetrix Remove Schematic Popup SIMPLIS Symbol Editor Add Separator Symbol Editor Popup Graph Popup Add Menu Graph Coe ce cee ee ee Add ltem Accelerator Hint Use Add Item to restore items deleted using Remove HFIP lee The above view shows the layout for SIMetrix SIMPLIS products For SIMetrix only products the top level menu choices will be slightly different The left hand pane shows the current menu system in a tree structured list The buttons on the right allow you to move delete or add new menu items and sub menus To Delete a Menu Item or Entire Sub menu Select the item you wish to delete on the left hand side then press Remove To subse
173. d coupling _factor Value between 0 and 1 which defines strength of coupling Note If more than 2 inductors are to be coupled there must be a K device to define every possible pair Examples Couple L1 and L2 together K12 Ll L2 0 98 Chapter 5 Components Couple L1 L2 and L3 K12 L1 L2 0 98 K23 L2 L3 0 98 K13 L1 L3 0 98 Resistors Capacitors and Inductors Resistors Resistors may be used in both SIMetrix and SIMPLIS modes Note that in SIMetrix mode a number of additional parameters may be specified These will not work with SIMPLIS and must not be specified if dual mode operation is required Select from Place Passives menu To edit value use F7 or select popup menu Edit Part menu as usual This will display the following dialog for resistors Choose Component Value Select Component Value Base 1 Series Decade 1k E6 E12 O E24 Result 1k A You can enter the value directly in the Result box or use the Base and Decade up down controls Additional Parameters Press Parameters button to edit additional parameter associated with the device such as temperature coefficients TC1 TC2 Refer to device in the Simulator Reference Manual for details of all device parameters Capacitors and Inductors Capacitors and inductors may be used in both SIMetrix and SIMPLIS modes Note that in SIMetrix mode a number of additional parameters may be specified These will not work with SIMPLIS
174. d in extreme cases could cause an out of memory condition See Also Real Time Noise analysis in the Simulator Reference Manual This includes the results of some comparisons between AC noise and real time noise Transfer Function 188 Transfer function analysis is similar to AC analysis in that it performs a swept small signal analysis However whereas AC analysis calculates the response at any circuit node from a usually single input source transfer function analysis calculates the individual responses from each source in the circuit to a single specified output node This allows for example the series mode gain common mode gain and power supply rejection of an amplifier to be measured in one analysis The same measurements could be performed using AC analysis but several of them would need to be run Transfer function mode also calculates output impedance or admittance and if an input source is specified input impedance Setting up a Transfer Function Analysis 1 Select menu Simulator Choose Analysis 2 Select TF check box on the right 3 Select TF tab at the top Enter parameters as described in the following sections Sweep Parameters Start value Stop value Defines sweep range stop and start values Points per decade Number of points Defines sweep range The number of points of the sweep is defined per decade Chapter 7 Analysis Modes for a decade sweep For a linear sweep you must enter the total number of p
175. d line that shows previously entered commands UndoBufferSize Numeric Default 10 Options Number of levels of dialog schematic undo See Creating a Schematic on page 53 UpdateClosedSchematics Boolean Allows SiMetrix to write to closed schematic if required See Closed Schematics on page 233 UpdateCurvesNoDeleteOld Boolean Default false Plot If true old curves are not Update deleted when using the Curve Update Curves feature Settings UpdateCurvesNoFixSelected Boolean Default false Plot If true update includes Update selected curves when Curve using the Update Curves Settings feature UseAltGraphPrintStyles Boolean Determines method of Options differentiating curves on dialog monochrome hardcopies See Graph Printing on page 327 UseGreekMu Boolean Default false No If true the u used to denote 10e 6 will be displayed as a greek pin graph axis labels Chapter 13 Sundry Topics Name Type Description User interface support UseNativeXpSplitters UserCatalog unsupported UserScriptDir UserSymbolsDir UserSystemSymbolDir UseSmallGraphCursor Boolean Text Text Text Text Boolean Default false The standard splitter bar in windows XP is flat and usually not visible In some SIMetrix windows the standard style has been bypassed in order to make these visible For example the legend panel in graphs Set this option to true to revert to standard XP
176. d party source This database is in the file ALL CAT which you will find in support directory under Windows and in the share directory under Linux The information you enter in the associate models dialog is stored in a file called USER_v2 CAT which you will find in the application data directory see Application Data Directory on page 325 You will also not need to perform the above procedure for many 2 and 3 terminal semiconductor parts even if they are not listed in the ALL CAT database SIMetrix runs a series of simulations on these models and attempts to determine what the device type is from their results If successful the association step demonstrated above will be skipped Finally there is a method of embedding association information within the model itself and such models will not require manual association The embedding method is described in Embedded Association on page 163 Chapter 3 Getting Started Chapter 3 Getting Started Overview This chapter describes the basic operation of SIMetrix and is aimed primarily at novice users The basic steps to simulate a circuit are as follows 1 Enter the circuit using the schematic editor See page 53 below 2 Add signal sources if relevant to your circuit See page 56 below 3 Specify analysis This includes what type of analysis and over what limits it should run See page 58 below 4 Run simulator See Running the Simulator on page
177. d press F7 Enter a suitable voltage Notes Soft initial conditions are implemented using the IC control and will also correctly apply an initial condition when Skip DC bias point is specified for a transient analysis The driving resistance for a soft initial condition is 1Q by default but can be altered using the ICRES simulator option To do this add OPTIONS ICRES nnn to the F11 window see Manual Entry of Simulator Commands on page 65 Hard Initial conditions are implemented using a voltage source with the DCOP parameter specified This feature is proprietary to SIMetrix and is not compatible with other SPICE simulators Refer to the Simulator Reference Manual for more information on voltage sources and the DCOP parameter Nodesets Nodesets are used to help convergence and also to coerce a particular state for circuits that have more than one possible DC solution More information about nodesets is given in the Simulator Reference Manual To Place a Nodeset 1 Select menu Place Connectors Nodeset 2 Place device at the desired location then select and press F7 Enter a suitable voltage 153 User s Manual Keeps Keeps form part of a system to limit the amount of data that is output during a simulation For some designs the data output can be too great to fit in the available disk space and in these situation the data output needs to be restricted For non hierachical designs the default is for all voltages and cu
178. d replace all instances But this is a simple task with a text editor operating on the ASCII file Saving in ASCII Format To save a schematic in the ASCII format use the menu File Save Special then select ASCII format Opening ASCII Schematics No special procedure is needed Just open the schematic in the usual way SIMetrix will detect that it is in the ASCII format automatically 87 User s Manual File Format Documentation for the install CD may be found at cd drive letter Docs File Formats schematic ascii format pdf Windows or cd mount point Docs File F ormats schematic ascii format pdf Linux Important The schematic will be saved in binary format as long as the following are satisfied 1 The ASCII format check box is not checked if using the Save Special menu 2 The file being saved does not already exist OR the file does exist and is not already a SIMetrix ASCII schematic So if you have an ASCII schematic and wish to convert it to binary the only method is to open it normally then save to a new file Creating Schematic Symbols Overview A large variety of schematic symbols are supplied with SIMetrix which should cover many uses However there will be occasions when you wish either to define your own new symbol perhaps to implement a hierarchical block or subcircuit or to modify one of the standard symbols This section describes how this can be done There are actually three different methods
179. del Library when in SIMPLIS mode will not be the same as in SIMetrix mode However SIMetrix is able to convert some SPICE models for use with SIMPLIS This conversion operation is performed behind the scenes and you don t necessarily need to know what is happening However it is very useful to understand the process that is being performed in order to understand the devices behaviour under SIMPLIS This conversion process is described in the next section SPICE to SIMPLIS Conversion SIMetrix is able to convert the following SPICE models types to SIMPLIS models Type Supported SPICE Conversion Method Implementation Diode Primitive model Parameter translation Zener Diode Primitive model or Simulated parameter extraction subcircuit BJT Primitive model Parameter translation MOSFET Primitive model or Simulated parameter extraction subcircuit Supported SPICE Implementation refers to the way the SPICE model must be implemented for the conversion operation to be supported SPICE models can be either primitive models using the MODEL control or can be sub circuits using SUBCKT ENDS Conversion Method describes the method used to perform the conversion Parameter translation is a simple process whereby the MODEL parameters are read from the model and used to compile a SIMPLIS model using a knowledge of the SPICE device equations Simulated parameter extraction is a more sophisticated and general purpose method that can be applied to
180. dge in waveform measured at 10 and 90 points Fall time of first falling edge in waveform measured at 20 and 80 points Fall time of first falling edge in waveform measured at user defined points Fall time of edge defined by cursor positions measured at 10 and 90 points Fall time of edge defined by cursor positions measured at 20 and 80 points Fall time of edge defined by cursor positions measured at user defined points Duty cycle measured over full span 249 User s Manual 250 Transient measurements Duty Cycle Cursor span Overshoot Absolute Auto Overshoot Relative Auto Overshoot Absolute Cursors define edge Overshoot Relative Cursors define edge Settling time 1 Settling time 0 1 Settling time 0 01 Settling time Custom Frequency Full Frequency Cursor span Distortion Full Distortion Cursor span AC measurements 3dB Low pass Access from menu More Functions menu More Functions menu More Functions menu More Functions menu More Functions menu More Functions menu More Functions menu More Functions menu More Functions menu Frequency menu More Functions menu More Functions menu More Functions menu More Functions Toolbar menu More Functions Description Duty cycle measured over span defined by cursor positions Maximum absolute value of
181. digital axes To change the analog grid order 1 Select Axes Reorder Grids 2 You will be presented with a list of currently displayed grids identified by their y axis title Use the up and down arrow buttons to arrange them in the order required then press Ok Note that the main axis the one at the bottom cannot be moved To change the digital axis order 1 Select menu Axes Reorder Digital Axes 2 Rearrange entries in list as described above for analog grids Plotting the Results from a Previous Simulation 1 Select the menu item Simulator Change Data Group 2 Select the name of the previous run or group that you require The current group will be highlighted Note that the AC analysis mode generates two groups One for the AC results and the other for the de operating point results Transient analysis will do the same if the start time is non zero 3 Plot the result you require in the normal way A word of warning If the schematic has undergone any modifications other than component value changes since the old simulation was completed some of the netnames may be different and the result plotted may not be of what you were expecting Note By default only the three most recent groups are kept This can be changed 239 User s Manual 240 using the GroupPersistence option using Set command see Set on page 297 or a particular group can be kept permanently using the Simulator Keep Current
182. div We will now plot the a graph of the voltage drop vs the load current This is the procedure 1 2 Select menu Probe Performance Analysis You will see a dialog box very similar to that shown in Plotting an Arbitrary Expression on page 228 In the expression box you must enter an expression that resolves to a single value for each curve For this example we use yatx vout 0 minimum vout yatx vout 0 returns the value of vout when time 0 minimum vout returns the minimum value found on the curve The end result is the drop in voltage when the load pulse occurs Press OK and the following curve should appear Chapter 9 Graphs Probes and Data Analysis 100 yatx vout 0 minimum vout V gt 3 8 eS 2m 10m 20m 40m 100m 200m 400m iload Histograms The procedure for histograms is the same except that you should use the menu Probe Histogram instead Here is another example This is a design for an active band pass filter using the simulated inductor method See Examples MonteCarlo 768Hz_bandpass sxsch We want to plot a histogram of the centre frequency of the filter 265 User s Manual 266 The example circuit has been set up to do 100 runs This won t take long to run less than 10 seconds on most machines This is the procedure Be O E Run the simulation using F9 or equivalent menu Select menu Probe Histogram Left click on the output
183. e Analog Device Reference in the Simulator Reference Manual for more information Power Supply Fixed Current Source Select menu Place Sources Power Supply or Place Sources DC Current Source to place a fixed voltage or current source These devices work in both SIMetrix and SIMPLIS modes AC Source The small signal analysis modes AC sweep and Transfer Function require AC sources for their input stimulus In SIMPLIS mode POP Periodic operating point also requires an AC source for its input To place an AC source select menu Place Sources AC Source for AC analysis or Place Sources AC Current Source Universal Source All of the sources described above can be used in both SIMetrix and SIMPLIS modes of operation In SIMetrix mode there is also a Universal source which provides the function of transient AC and DC sources all in one device In addition the Universal source may be used to create a random noise source To place a universal source select menu Place Sources Universal Source or Place Sources Universal Current Source 57 User s Manual To edit a universal source select the device and press F7 or popup menu Edit Part This will display the following dialog box A Choose Source Pulse Sine Noise ac oc Text Enable DC Time Frequency C Enable AC Period 1004 i Frequency 10k j Pulse Width 50u Duty 505 4 i O Sine Rise 500n S Equal rise and fall O Noise F
184. e 2 input Show voltage at transistor NAND node O Place Op amp Place 2 input OR P Place PNP Place digital Show pinname transistor pulse at cursor Q Repeat arc symbol editor R Place resistor Place 2 input Repeat last NOR probe S Place switch Show netname at cursor T Place Switch window transmission line U Place fixed current probe V Place voltage Place digital Paste source VCC Ww Place waveform Select Window generator X Place ideal Place 2 input Cut transformer XOR Y Place terminal Z Place zener Undo diode schematic 2 Place NMOS 4 term transistor 3 Place PMOS 4 term transistor 4 Place resistor z shape 5 Chapter 10 The Command Shell Key Unshifted Shift Control Shift Control 6 7 8 9 Key Unshifted Shift Control Alt F1 Help F2 Step script Pause script Resume script F3 Start wire schem More analysis functions graph F4 Probe Voltage Quit immediate Close window F5 Rotate schem symbol Cursor to previous Cursor to next peak peak graph graph F6 Mirror schem symbol Flip schem Cursor to next trough symbol editor graph Cursor to previous trough graph F7 Edit Part schem Edit literal value Move value Edit Ref cursor to next peak schem Ref MOS graph cursor to previous value Edit property pin arc peak graph symbol editor F8 Edit reference schem Ref cursor to Move ref Ref cursor to next trough previous trough graph graph F9 Start simulation Open Last
185. e Plot Fourier of Curve Cursor span which uses cursor span Custom Settings With menu Probe Fourier Probe Voltage Custom you will see the dialog below With the menus Probe Fourier Arbitrary or command shell menu Graphs and Data Fourier a dialog box similar to that shown in Plotting an Arbitrary Expression on page 228 will be displayed but will include a Fourier tab Click on the this tab to display the Fourier analysis options as shown below gt Chapter 9 Graphs Probes and Data Analysis Pal Define Fourier Plot Fourier Method FFI O Continuous Fourier Signal info C Know fundamental frequency Frequency 100 Plot Frequency display Magnitude Resolution Hz 100 Oa Start freg Hz 0 Phase Stop freg Hz 10k C Log X Axis m FFT interpolation The spectrum will be calculated using Num points 4096 an exact number of cycles of the fundamental frequency Order 2 Estimated calculation time 0 00369 Advanced Options Method SIMetrix offers two alternative methods to calculate the Fourier spectrum FFT and Continuous Fourier The simple rule is use FFT unless the signal being examined has very large high frequency components as would be the case for narrow sharp pulses When using Continuous Fourier keep an eye on the Estimated calculation time shown at the bottom right of the dialog A description of the two techniques and their pros and cons follows FFT Fa
186. e Status shown as Started On Windows 2000 and XP 1 Open the Windows Control Panel Chapter 1 Introduction 2 Select the Administrative Tools icon 3 Select the Services icon 4 You should see FLEXIm License Manager as one of the services with the Status shown as Started Stopping and Starting the Service Proceed as for Monitoring Service Select flexlm item then for Windows NT press Start or Stop button and for Windows 2000 XP right click then select appropriate menu item Service Installation Options The installs program has an option allowing the license file to be located in locations other then the directory containing the license manager You can also change the name and location of the log file and the name of the service The full syntax is installs n service_name c license_path 1 logfile_path service_name Name of service enclose name in quotation marks if it contains spaces The default is Flexlm license manager license_path File system path of license file Path is relative to current working directory logfile_path File system path of log file Path is relative to current working directory Removing the License Server Service To uninstall the license server open a command prompt window i e a DOS prompt then CD to the directory where you copied the license manager files Type at the command line installs r This will attempt to stop the license server before uninstalling it
187. e at this location This allows modification of the UI Changing this setting has no effect until you restart SIMetrix Start up Script Name of script that is automatically run on startup You can place custom menu or key definitions in this file Editor Text editor called by EditFile command as used by a number of menus Default is notepad 329 User s Manual 330 PSpice inifile Set this file location if you wish to use the PSpice Schematics translator See PSpice Schematics Translation on page 117 for more information System Symbols Location Directory location where the standard symbols are located User Symbols Location Directory where user symbol libraries are expected to be located Note you can place symbol libraries anywhere This directory is simply a location that some UI functions use as a default Shell Scripts Script Options Echo all messages If set all script lines will be displayed in the message window This will result in a great deal of output and will slow down the whole program operation Only set this if you are debugging your own scripts Don t abort scripts on error Normally scripts abort if an error is detected Check this box to disable this behaviour Keys disable The built in key definitions can be disabled allowing you to define your own See User Defined Key and Menu Definitions on page 350 for more info on how to do this Disable standard key definitions Disable key de
188. e place holder symbol then menu Hierarchy Replace Component 85 User s Manual Printing To relocate files use the system s file handling tools to move the component files then select menu Hierarchy Update Symbols Printing a Single Schematic Sheet 1 2 Select menu File Print If there is a graph window currently open See Graphs Probes and Data Analysis on page 212 you can choose to plot the schematic alongside the graph on the same sheet Select your choice in the Layout section In the Schematic box select an appropriate scale Fit area will fit the schematic to a particular area relative to the size of paper If multiple sheets are chosen a small overlap will be included Fixed grid means that the schematic s grid will be mapped to a fixed physical size on the paper The sizes are in inches 1 inch 25 4mm So 0 3 means that grid square on the displayed schematic will be 0 3 inches or 7 5mm on the printed sheet Printing a Hierarchical Schematic 1 2 3 Select menu File Print Hierarchy You will be presented with a complete list of schematics used in the current hierarchy Select the schematics you wish print and Ok Select options as appropriate then Ok File Operations 86 Saving For normal save operations use the File Save or File Save As menus To save all the sheets currently open use File Save All Exporting Schematic Graphics You may export schematic graphics
189. e rebuilds the current graph sheet using the latest available data This allows you to randomly probe a schematic and then update the curves with new results for a new simulation run The Plot Journal feature allows you to save the plots in the current graph sheet for later reconstruction This doesn t save the data it saves the vector names and expressions used to create the graph s curves In fact this is done by building a SIMetrix script to plot the curves Update Curves Make sure that no curves are selected then select graph menu Plot Update Curves The curves currently on the graph sheet will be redrawn using the current simulation data Although this would usually be the latest simulation run you can also use this feature to restore the curves back to those from an earlier run Use the Graphs and Data Change Data Group menu to select earlier data For more information see Plotting the Results from a Previous Simulation on page 239 Options By default all curves are redrawn that is the older ones are deleted You can change this behaviour so that older curves are kept Select menu Plot Update Curves Settings then uncheck the Delete old curves box If there are curves that you would like to remain fixed and so won t be updated simply select them first This behaviour can be overridden using the menu Plot Update Curves Settings Simply uncheck the Ignore selected curves box Plot Journals First create a
190. e world This is a module port symbol which can be found in the schematic menu Hierarchy Place Module Port Important do not use the normal Terminal symbol It is recommended that any model definitions are included in the subcircuit definition This makes the subcircuit self contained If you have referenced models in the device library you can import them into the schematic automatically using the schematic menu Simulator Import Models They will be placed in the simulator command window which can be opened by pressing F11 Alternatively you can enter them in the command window manually Stage 2 Netlist Circuit To create a subcircuit netlist select schematic menu Simulator Create Netlist as Subcircuit You will be first be prompted for a subcircuit name This name will also be used for the file name with extension MOD After entering the name you will be asked to specify the subcircuit pin order 150 Chapter 5 Components When you close this box the subcircuit will be created and its text will be displayed Calling a Sub circuit in a Schematic To call a sub circuit in a schematic you must choose or create a symbol for it The symbol must have the same number of pins and ideally it would also have the same pin order In other words the order of the nodes in the SUBCKT line would be the same as the pin order of the symbol The matching of SUBCKT node order and symbol pin order is n
191. eR 316 12 7766017 sourceR 3162 27766017 sourceR 1000 10 i z 1001 gt 101 1p taili Example 2 10u 100p The following circuit is a simple model of a full bridge switching amplifier used to deliver a controlled current into an inductance 250n MA L 100r Tan 12 48 Tez c1 O a e 22m R6 IRFP2 0 IRFP260 o eg rf 2 2 2 2 Al R2 A E IRFP2b0 IRFP260 2 2 Si P 2 2 R3 xX X R4 Ma at a4 p ys i Sources V2 and V3 have been defined to be dependent on a parameter named duty which specifies the duty cycle of the switching waveform See EXAMPLES BRIDGE BRIDGE sxsch 197 User s Manual This was setup to perform a multi step analysis with the parameter duty stepped from 0 1 to 0 9 This is the result duty 0 9 1 1 uty 0 7 lt z duly 0 5 rt g 5 S duty 0 3 4 duty F 0 1 1 0 0 2 0 4 0 6 0 8 1 1 2 14 1 6 1 8 2 Time mSecs 200ySecs div Safe Operating Area Testing 198 Overview Safe Operating Area SOA is not a separate analysis mode but a feature that can be enabled with DC or Transient analyses With SOA testing you can set maximum and minimum limits for any simulation quantity and the simulator will display when those limits are violated To use SOA testing you must do two things 1 Define the SOA limits for the models or d
192. earching To open parts browser select schematic menu Place From Model Library All devices for which models have been installed will be displayed and listed under an appropriate category If you can t find a device under the expected category select the All Devices category Every single device currently installed will be displayed here Note for large libraries you may have to wait a second or two to see the list of devices when selecting this category If you have installed your own models see Parts Management Installing Models below you will always find them listed under the category All User Models and if installed within the last 30 days under Recently Added Models If you select a part under All User Models or Recently Added Models you may be presented with the Associate Model dialog box This will happen if SIMetrix is unable to determine what symbol to use for the model This is explained in Placing New Model on Schematic on page 160 157 User s Manual Parts Management Installing Models 158 Overview The process of installing third party SPICE models has always been a fundamentally tricky one The difficulty has been associating the SPICE model which is the electrical definition of the device with the schematic symbol which is the pictorial representation of it A model provides an electrical description of the device but not what schemat
193. eate nodeset file to speed DC convergence Set option Displays the value of an expression Can be used to export data to a file in ASCII form Delete option DefKey Key_Label Command_string option_flag DefKey is used to define custom key strokes Key_Label Code to signify key to define See table below for list of possible labels All labels may be suffixed with one of the following SCHEM Key defined only when a schematic window is currently active GRAPH Key defined only when a graph window is currently active SHELL Key defined only when the command shell is currently active SYMBOL Key defined only when a symbol editor window is active If no suffix is provided the key definition will be active in all Chapter 11 Command and Function Reference windows Command string A command line command or commands to be executed when the specified key is pressed Multiple commands must be separated by semi colons Unless the command string has no spaces it must wholly enclosed in double quotation marks option_flag A number between 0 and 5 to specify the manner in which the command is executed These are as follows 0 Default Command is echoed and executed Any text already in command line is overwritten 5 Immediate mode Command is executed immediately even if another operation such as a simulation run or schematic editing operation is currently in progress For other options the command is n
194. econd order response See Laplace Expression below for details of the expression syntax Frequency scale factor Multiplier for frequency Device type Transfer function Expression defines output input Impedance V I Two terminal device expression defines voltage current Admittance I V Two terminal device expression defines current voltage Input Input configuration for transfer function Output Output configuration for transfer function 145 User s Manual 146 Laplace Expression When you close the box a symbol will be created according to the selections you make for device type input and output As seen in the above examples the transfer function of the device is defined by the model parameter LAPLACE This is a text string and must be enclosed in double quotation marks This may be any arithmetic expression containing the following elements Operators A means raise to power Only integral powers may be specified Constants Any decimal number following normal rules SPICE style engineering suffixes are accepted S Variable This can be raised to a power with or by simply placing a constant directly after it with no spaces E g s 2 is the same as s2 Filter response functions These are described in the following table Function Syntax Filter Response BesselLP order cut off Bessel low pass BesselHP order cut off Bessel high pass ButterworthLP order cut off Butterworth low pass
195. ed vector argument 1 crosses the given y value argument 2 in the direction specified by argument 4 If the vector never crosses the given value an empty result is returned The sampled input vector is interpolated to produce the final result Interpolation order is specified by argument 3 311 User s Manual 312 XY real real Returns a vector with y values of argument land x values of argument 2 This function provides a means of creating X Y plots using the GRAPH control See the Command Reference chapter of the Simulator Reference Manual for details YFromX real real real Input vector Y value Interpolation order Returns an array of values usually a single value specifying the vertical value of the specified vector argument 1 at the given x value argument 2 If the given x value is out of range an empty result is returned The sampled input vector is interpolated to produce the final result Interpolation order is specified by argument 3 Chapter 12 Monte Carlo Analysis Chapter 12 Monte Carlo Analysis Overview Monte Carlo analysis is a procedure to assess manufacturing yields by repeating simulation runs with varying applied random variations to component parameters The technique is very powerful and usually gives a more realistic result than worst case analysis which varies component values to their extremes in a manner which produces the worst possible result The implementation of Mo
196. ed functions mechanism They are defined as scripts but behave like functions Name Description Page BPBW data db_down Band pass bandwidth 270 Bandwidth data do_down Same as BPBW 270 CentreFreq data db_down Centre frequency 271 Duty data threshold Duty cycle of first pulse 271 Fall data start end Fall time 272 Frequency data threshold Average frequency 273 269 User s Manual Name Description Page HPBW data db_down High pass bandwidth 273 LPBW lt data db_down Low pass bandwidth 274 Overshoot data start end Overshoot 274 PeakToPeak data start Peak to Peak 275 end Period data threshold Period of first cycle 275 PulseWidth data threshold Pulse width of first cycle 279 Rise data start end Rise time 276 XatNthY data yValue n X value at the Nth Y crossing 276 XatNthYn data yValue n X value at the Nth Y crossing with 276 negative slope XatNthYp data yValue n X value at the Nth Y crossing with 276 positive slope XatNthYpct data yValue n X value at the Nth Y crossing y 277 value specified as a percentage YatX data xValue Y value at xValue 277 YatXpct data xValue Y value at xValue specified as a 277 percentage BPBW Bandwidth BPBW data db_down Finds the bandwidth of a band pass response This is illustrated by the following graph 270 Chapter 9 Graphs Probes and Data Analysis First 3dB crossing after peak x2 Function return x
197. ed to read too much about it Here we describe the less obvious procedures For full documentation see Schematic Editor on page 70 If you have SIMetrix SIMPLIS make sure you are in the correct mode before entering a schematic See above section 53 User s Manual 54 To Place a Component If it is a simple device which only needs a value such as a resistor or capacitor select the appropriate symbol from the tool bar or Place menu For other devices that require a part number it is easiest to use the parts browser Select menu Place From Model Library and select your desired device To Change Value or Device Type for a Component First select it then double click or select schematic popup Edit Part or press F7 Note that the double click behaviour first appeared in version 5 1 and may be disabled for backward compatibility See Using the Options Dialog on page 326 for details A dialog box appropriate for the type of component will be displayed For devices requiring a model name a list of available types will appear To Rotate Mirror or Flip a Component Use the rotate toolbar button C or key F5 to rotate a component You can repeat pressing this button key until the desired orientation is reached It sequences through all 8 possible orientations This operation can be performed while a component is being placed or while a block is being moved or copied see below You can also select a component or block t
198. eeeeeeeeeeeeeeeeeeeeeeenneeeeeeeees 308 Mean1 real real real 00 0 ee eeeseeeeeeeeeeseeeeeeaes 308 Minidx real COMPIeX eee eeeeeeeeeeeeeeeeeeeeeeeeenneeeees 308 Minima real real String esseceeeseeeeeeeeeees 308 Minimum real complex real real 00 309 Norm real COMPIeX eeecceeeeseeeseeteeeeneeseeeeeeenteeeee 309 ph real complex phase real complex 65 309 phase_rad real COMpleX ce eeeceeeeeeeeeerteeeeeeeee 309 Range real complex real real 1 309 re real complex real real complex ceeee 309 Ref real COMpleXx cce teeceeceeedenceresceeesectensseeeetees 309 Rms real icici ieeecsi eve eee 310 RMS1 real real real ccce 310 TNA real 2 rr esis ceececdeee de cetendeeneettelete donee steieess 310 RootSumOfSquares real real real 310 SIQM Oa casi ecestecdectecenestecstota aenn aare as 310 sin real complex 0 ee eeeeeeeeeeeeeeeeeeeeeesneeeeenaeeeeneeees 310 Sqrt real COMPIeX cee eceeeeeeeeeesteeeeeeeeeeseeeeeenteeeeeaes 310 SumNoise real real real cseceeeeeereeees 310 tan real COMPIeX ee eeeeeeeceeeeeeeeeeeeeeenteeeeeneeeeenees 311 Truncate real real reall 0 0 eeeeeeeeeseneeeeeeees 311 UnitVeC real c0 chicane eevee 311 v ector real iia ie i eee line ake 311 XFromyY real real real real 2 0 311 XY real reall ss sesh ele niel teeta 312 YFromX real real reall
199. efined by start x value and end x value If the vector is complex the operation will be performed on the magnitude of the vector mean real complex Returns the average of all values in supplied argument If the argument is complex the result will also be complex Mean1 real real real Vector Start x value Default start of vector End x value Default end of vector Returns the integral of the supplied vector between the ranges specified by arguments 2 and 3 divided by the span arg 3 arg 2 If the values supplied for argument 2 and or 3 do not lie on sample points second order interpolation will be used to estimate y values at those points minidx real complex Returns index of the array element in argument with the smallest magnitude Minima real real string Vector Maximum value Default 00 Options array Possible values are xSort Sort output in order of x values nolnterp Don t interpolate Returns array of values holding every minimum point in the supplied vector whose value is below argument 2 The value returned if no nterp is not specified is obtained by fitting a parabola to the minimum and each point either side then calculating the x y location of the point with zero slope If noJnterp is specified the values are those found in argument without any interpolation The vector returned by this function has an attached reference which contains the x values of the minimum points If xSo
200. el property of F will be treated as a such a device An additional voltage source will be created by the netlist generator and connected to pins 3 and 4 to be used as the controlling current H Current controlled voltage source As F above but has a voltage output For a list of valid device types and their signifying letters see Summary of Simulator Devices on page 122 In some respects the special behaviour of model property values X F and H is legacy from the past The recommended method of customising netlist output is to use the template property but this was not supported in very early versions of SIMetrix Chapter 4 Schematic Editor Property name Function netname scterm tol lot match schematic_path mapping params template valuescript incscript decscript handle simulator If this property is present on a symbol all nets connected to any of its pins will be named according to the value property The netname property is used by the Terminal component in the Symbols menu The Terminal component forces the net to which it is attached to have a user specified name The value of the netname property will be used in the absence of a value property Identifies the component as a Module Port These identify connections in hierarchical blocks These are used for Monte Carlo analysis to specify tolerances See page Path of schematic in hierarchical designs Re
201. en a simulation run gets out of date The file containing the data gets deleted at a time set by the above options not necessarily when the data is no longer needed As long as the file exists the data can be recovered by calling File Data Load or File Data Load Temporary Data which re builds the location data Model Library Library Diagnostics Determines whether messages are displayed when models are found in the library Model read in If the Don t abort on unknown parameters check box is cleared the simulation will abort if models are found that have parameters unsupported by SIMetrix File Locations Locations in your files system of various files and folders needed for correct operation of SIMetrix Scripts Location of script directory This directory is searched for any scripts you run Only change this setting if you are actually moving the script directory Changing this setting has no effect until you restart SIMetrix Start up Current working directory on start up Temp Data Location of temporary simulation data files Changing this setting has no effect until you restart SIMetrix Note that this should always be a local directory That is it must not be on a remote network partition Built in Scripts This is the first location that SIMetrix searches for scripts Much of the user interface is implemented with scripts and these are all internal to the program These can be overridden by placing scripts of the same nam
202. ense manager through a firewall The license manager communicates with the application using the TCP IP protocol the same protocol used for the Internet and virtually every LAN TCP communications always specify a port which is a number between and 64000 and identifies a kind of communication channel By default the FLEXIm license manager uses one of the ports in the range 27000 to 27009 and the application will scan through these in sequence In most situations the server will use port 27000 and as this is the first port to be scanned by the application everything will work fine In some situations the server might use another port usually because 27000 etc is already in use With the default settings this may cause a start up delay as SIMetrix searches for the correct port This problem mostly occurs when running under Windows In this situation specifying the exact port number at both ends will resolve this problem See below to find out how to do this If you are accessing the license manager through a firewall you will need to open up a suitable TCP port In this situation it is best to specify the exact port number so that only one port needs to be opened Specifying the License Server Port To specify the port used by the license server you must edit the license file Simply add the port number to the end of the SERVER line E g SERVER NT_SERV1 000CF1C97B71 27001 23 User s Manual 24 The above specifies
203. ent and voltage source current calculated at the most recent analysis point The values generated can be read back in as nodesets to initialise the de operating point solution nodeset If specified the values are output in the form of a nodeset command which can be read back in directly Only node voltages are output if this switch is specified Otherwise currents in voltage sources and inductors are also output filename File where output is written This command is intended as an aid to DC operating point convergence Sometimes the de operating point solution is known from a previous run but took a long time to calculate By applying the known solution voltages as nodesets prior to the operating point solution the new DC bias point will be found much more rapidly The method is tolerant of minor changes to the circuit The old solution may not be exact but if it is close this may be sufficient for the new solution to be found quickly Chapter 11 Command and Function Reference If SaveRhs is executed after an AC analysis the values output will be the real part only Set Set temp option_spec option_spec Defines an option temp If specified the option setting will be temporary and will be restored to its original value when control returns to the command line i e when all scripts have completed option_spec Can be one of two forms Form 1 option_name Form2 option_name option_value option_name can be any of
204. ently displayed graph is from a transient analysis and has an x axis of Time and you are also probing the results of a transient analysis then the new curve will be added to the displayed graph If however the displayed curve was from an AC analysis its x axis would be frequency which is incompatible In this case a new graph sheet will be created for the new curve If you want to force a new graph sheet to be created press F10 This will create an empty graph sheet The menus Probe Voltage New graph sheet Probe Current New graph sheet will always create a new graph Chapter 9 Graphs Probes and Data Analysis Functions The following table shows all available random probe functions Many of these can be found in the schematic s Probe menu while others are only available from Probe More Probe Functions Function Single Ended Voltage Single Ended Voltage AC coupled Single Ended Voltage dB Single Ended Voltage Phase Single Ended Voltage Fourier Single Ended Voltage Nyquist Single Ended Voltage Normalised dB Single Ended Voltage Group delay Differential Voltage Differential Voltage dB Differential Voltage Phase Differential Voltage Fourier Differential Voltage Nyquist Differential Voltage Normalised dB Differential Voltage Group delay Relative Voltage dB Relative Voltage Phase Relative Voltage Nyquist Relative Voltage Normalised dB Relative Voltage Group delay
205. erence Manual REF lt REF gt Returns the component reference of the device using the same rules that are used when the template property is not present The rules are if MODEL property is blank OR MODEL is a single character AND first letter of REF property equals MODEL property lt ref gt REF otherwise lt ref gt MODEL lt sep gt REF Where lt sep gt is the separator character This is usually but can be changed at the netlist command line See Netlist command syntax in the Script Reference Manual If lt REF gt is used for a series or parallel repeat sequence it will be appended with lt SEP gt lt STEP gt where lt STEP gt is the sequence number for the series parallel function See below REPEAT lt REPEAT var_name num lt line gt gt Repeats line num times var_name is incremented on each step var_name may be used in an expression to define device or node names The following example creates a subcircuit that define an RC ladder circuit with a variable number of sections defined by the property NUM The resistance of each section is defined by the property RES and the capacitance by the property CAP Note that as explained above templates are resolved in two passes In the first pass the property names enclosed by are substituted with their values while expressions and keywords are left untouched In the second pass the keywords and expressions are processed subckt ladder 1 SNUM
206. erminal bulk to VDD pmos_a3_vdd_new J W 1u L 1u pmos_a_new W 1u L 1u Q4 P channel 4 terminal In the Micron versions of SIMetrix these will by default be available from the component toolbar These symbols have the model name N1 for the N channel types and P1 for the P channel types These names can of course be changed after being 119 User s Manual 120 placed on the schematic but this would be time consuming to have to do each time To avoid having to do this you can do one of the following Modify your SPICE model files so the devices are always called N1 and P1 Modify the standard symbol so the model name corresponds to your SPICE models Create a new set of symbols for each process you use The best course of action is probably to create a new symbol for each process Once you have created the new symbols you can modify the toolbar buttons so that they call up your new symbols instead of the standard ones You must do this using the DefButton command which redefines toolbar buttons To make permanent changes the DefButton command should be put in the startup script Here is the procedure 1 Select command shell menu File Scripts Edit Startup If you are using Linux you might first need to define a suitable text editor for this menu to work The default is gedit 2 Enter a DefButton command for each toolbar button you wish to redefine For the MOS symbols the commands will be one or more co
207. etrix also supports another form of LIB used by model files designed for Hspice See the Simulator Reference Manual for details Drag and Drop to Schematic You can install a model file to a schematic by picking it up in windows explorer and dropping it onto the schematic window This will insert a LIB control see above with a path to the file you dropped This installs the model file to be local to that schematic Library Diagnostics When enabled library diagnostics display messages showing the progress of the location of device models To enable disable select File Options General then Model Library tab Local Models You can also enter a model or subcircuit definition in the schematic s F11 window However if you enter a model in this manner it will only be available to that schematic Library Indexing Mechanism This is a technique used to speed the search for models and subcircuits It is completely transparent and requires no action from the user SIMetrix creates an index file for each library specification it encounters either installed globally or referenced using LIB This index files contain details of the file locations of models and subcircuit definitions referenced by the library specification These index files can then be used for later simulation runs to speed the search for models and subcircuits Index files are automatically rebuilt if any of the library files referenced are modified Modifications are detected
208. etrix simulation mode 2 Back annotated initial conditions are attached to schematic instances and will be faithfully reproduced if for example a schematic block is copied and pasted to another schematic Please read all of the sections below on back annotation and ensure you correctly understand all the issues involved 209 User s Manual 210 How to Back annotate a Schematic Simply select menu Simulator Initial Conditions Back annotate You will notice a second or two of activity in the schematic and then the operation is complete You should note that SIMetrix SIMPLIS does not distinguish between initial conditions that are back annotated and initial conditions that are applied manually After running the back annotation algorithm you will not be able to restore the initial condition value to those set before You can however use Undo in the normal way and in fact the back annotation operation will be reversed with a single Undo operation Disable Enable Initial Conditions To disable initial conditions select menu Simulator Initial Conditions Disable Note that this will disable all initial conditions defined at the top level not just ones that are back annotated To re enable use the menu Simulator Initial Conditions Enable Back annotation Errors If you get the error message The following instances have initial condition values but do not support back annotation it means that the SIMPLIS_TEMPLATE property is pro
209. evices you are using 2 Enable and configure SOA testing Item 1 above is covered in detail in the Simulator Reference Manual see section titled SETSOA and also the LIMIT parameter described in the section titled MODEL Setting up simple limit tests using some simple schematic symbols is described below Defining Simple Limit Tests Schematic Symbols Three schematic symbols are provided that allow the definition of simple limit tests that report the following Chapter 7 Analysis Modes 1 Over and under voltage on a single node 2 Over and under current on a single device pin 3 Over and under differential voltage on a node pair Use the following menus to place these devices Place Probe Watch Voltage Place Probe Watch Current Place Probe Watch Differential Voltage Each of these symbols can be edited in the usual way Each has three parameters that specify 1 The minimum limit Use a large negative number e g 1e100 if you don t wish to specify a minimum limit 2 The maximum limit Use a large positive number e g 1e100 if you don t wish to specify a maximum limit 3 A label The default value is REF that will resolve to the device s component reference You can enter any literal value instead Setting Up SOA Testing 1 Select menu Simulator Choose Analysis 2 Select the SOA tab 3 Under SOA mode choose either Summary output or Full output In summary output mode only the first vio
210. explained in the overview generic components are devices that are defined by one or more parameters entered by the user after the component is placed The following generic components are available Device SIMPLIS Page support Saturable Inductors and Transformer No 133 Ideal Transformer Yes 135 Inductor Yes 137 Capacitor Yes 137 Resistor Yes 137 Potentiometer Yes 138 Transmission Line Lossless No 139 Transmission Line Lossy No 139 131 User s Manual Device SIMPLIS Page support Voltage source Yes 139 Current source Yes 139 Voltage controlled voltage source Yes 140 Voltage controlled current source Yes 140 Current controlled voltage source Yes 140 Current controlled current source Yes 140 Voltage controlled switch No 140 Voltage controlled switch with Hysteresis Yes 141 Device Page Non linear transfer function 143 Laplace transfer function 145 Non linear resistor 146 Non linear capacitor 146 Non linear inductor 146 Analog Digital converter 141 Digital Analog converter 141 Digital counter 142 Digital shift register 142 NAND NOR OR AND gates 142 Digital bus register 142 SIMPLIS Primitive Components The following components are only available with the SIMetrix SIMPLIS product and when in SIMPLIS They can all be found under the menu Place SIMPLIS Primitives For full details see the SIMPLIS Reference Manual 132 Chapter 5 Components Device Comparator Set reset flip
211. f netnames have never been created then they won t be updated during the run as by default SIMetrix will not update a closed file This problem can be resolved by giving SIMetrix permission to update schematic files that are closed To do this type at the command line Set UpdateClosedSchematics This only needs to be done once Note that you can only do this with the full versions of SIMetrix This problem won t arise if you always run every schematic at least once while it is open If you do this the netnames will be updated and you will be promted to save the schematic before closing it This wasn t the case with SIMetrix version 4 2 and earlier and the above problem is most common with schematics created with those earlier versions Multiple Instances An issue arises in the situation where there are multiple instances of a block attached to the same schematic Consider the following top level circuit u1 u2 VP fastammp sch yp fastamp sch 1 VINP VOUTP VINP VOUTP x T VINN VOUTN VINN VOUTN z e v3 VN VN 1K FN AC1 0 Pulbe O 10m 0 5n Sn 500 Tuy E1 R2 R1 1Meg 1Meg me keh oira ia c v2 233 User s Manual This has two instances of the block FASTAMP SCH U1 and U2 Suppose you wanted to plot the voltage of a node inside U1 The schematic FASTAMP SCH is open but to which block does it refer The answer is that it
212. f rows and columns equal to the number of logic families listed in the header Both column and rows represent inputs The table defines how inputs from different families are treated when they are connected The entry may be one of four values 295 User s Manual 296 Row take precedence Column takes precedence Doesn t matter Currently identical to ROW Incompatible inputs cannot be connected Out out resolution table A table with the number of rows and columns equal to the number of logic families listed in the header Both column and rows represent outputs The table defines how outputs from different families are treated when they are connected The entry may be one of four values Row take precedence Column takes precedence Doesn t matter Currently identical to ROW Incompatible outputs cannot be connected Reset Reset Frees memory associated with most recent simulation run It is not normally necessary to use this command unless available memory is low and is needed for plotting graphs or other applications Note that Reset does not delete the data generated by a simulation only the internal data structures set up to perform a run These are automatically deleted at the beginning of a new run Any graph curves created by fixed probes i e GRAPH controls will be updated when this command is executed SaveRhs SaveRhs nodeset filename Creates a file containing every node voltage inductor curr
213. finitions Note that many of the key assignments are defined as menu short cuts their name appears in the menu text These are not disabled by this option Does not take effect until you restart SIMetrix File Extensions Defines extensions used for the various files used by SIMetrix Note that the default settings for three file types have five letters rather than the usual three This is to avoid conflict with other applications where file associations are involved Some file servers on network systems do not support five letter extensions If you are using such a system you will need to change these settings For each setting the supported extensions are separated by a semi colon The first in the list is the default So for example the default schematic extension is sxsch so when you save a schematic without giving an extension it will automatically be given the extension sxsch Schematic Files Extensions used for schematic files Schematic Components Extensions used by schematic component files Data Files Extensions used for simulation data files Text files Supported extensions for text files File Scripts Edit File will Chapter 13 Sundry Topics list all files with these extensions Symbol Files Extension used for binary schematic symbol files This is for future expansion Currently this setting has no effect Logic Def Files Files used for logic definitions for the digital simulator s arbitrary logic block If the
214. for the 700 series semi custom arrays are enabled if this is set AlwaysUseMarkers Boolean Graphs are printed with Options markers even for colour dialog printers AnnoMinSuffix Numeric Default 1 Minimum suffix used for automatic generation of schematic component references AutoStartWire Boolean Default False Options Only effective if dialog AutoWireEnabled is False Selects mode whereby a wire is started when the cursor is brought close to a pin or wire termination This mode is on automatically when AutoWireEnabled is True AutoWireEnabled Boolean Default True Options Smart wiring is on if this is dialog True AWAllowRouteThruConnected Boolean Default True Options Controls whether the smart dialog wire algorithm is allowed to route wires through existing wires that connect to the destination or target AxisPrintWidth Numeric Default 0 5 Options Width of printed axis in dialog mm See also CurvePrintWidth and GridPrintWidth Chapter 13 Sundry Topics Name Type Description User interface support BiasAnnoPrecision Numeric Default 6 Options Precision of values dialog BiScriptDir BuildAssociations BuildModelLibs BuildPreferenceSettings BuildSymbolLibs CachePathSymbols unsupported CancelOnFocusLost Text Text Text Text Text Boolean Boolean displayed for schematic DC bias annotation This is the first location that Options SIMetrix searches for dialog scrip
215. frequency sweep it is only necessary to calculate it at the start of the run For AC analysis to be meaningful at there must be at least one voltage or current source on the circuit with an AC specification To find out how to set one up see Circuit Stimulus on page 56 Setting up an AC sweep 1 Select menu Simulator Choose Analysis 2 Select AC check box on the right 3 Select AC tab at the top Enter parameters as described in the following sections Sweep Parameters Start value Stop value Defines sweep range stop and start values Points per decade Number of points Defines sweep range The number of points of the sweep is defined per decade for a decade sweep For a linear sweep you must enter the total number of points Define Sets up desired sweep mode See Setting up a Swept Analysis on page 179 Monte Carlo and Multi step Analysis See page 194 Data output Check the Save all currents check box to enable the output of all current data including semiconductor devices If this box is not checked the current into devices such as transistors and diodes will not be saved In AC analysis the CPU time required to output data can be very significant relative to the solution time so you should be aware that checking this box may slow down the simulation significantly Note that this check box only affects AC analyses See Also AC in Simulator Reference Manual Chapter 7 Analysis Modes Example
216. from Version 4 5 Non linear Magnetics The non linear magnetics models and schematic support has been completely overhauled The models and GUI for the older system are still supported but the menus for them have been removed You can still create and edit devices using the old model but the procedure is different Instead of using the Place Passives Saturable use the Place From Symbol Library menu then choose one of the following Passives Inductor Saturable Passives gt Transformer Saturable Passives Transformer 2 Secs Saturable For new designs we recommend using the new system It supports an arbitrary number of windings and the models are more accurate Use menu Place Magnetics Saturable Transformer Inductor Chapter 1 Introduction Use of u Prefix in Graphs Graph axes are no longer labelled using the greek letter u to represent 10 and instead the letter u is used This is for compatibility with non English operating system versions Use the option variable UseGreekMu to change this so type at the command line Set UseGreekMu Upgrading from Version 5 0 Double Click to Edit Schematic Devices Double clicking a schematic instance will now invoke the editing action in the same way as the F7 key Double clicking outside an instance will start a new wire in the same manner as earlier versions You can revert to the old behaviour whereby double clicking always starts a new wire using an option
217. from a schematic The first approach is to fix voltage or current probes to the schematic before or during a run SIMetrix will then generate graphs of the selected voltages and or currents automatically Normally the graphs for fixed probes are opened and updated while the simulator is running The probes have a wide range of options which allow you to specify for example how the graphs are organised and when and how often they are updated These probes are known as fixed probes The second approach is to randomly probe the circuit after the run is complete You can also do this during a run by pausing first With this approach the graph will be created as you point the probe but will not be updated on a new run These probes are known as random probes You do not need to make any decisions on how you wish to probe your circuit before starting the run You can enter a circuit without any fixed probes run it then randomly probe afterwards Alternatively you can place a single fixed probe on an obvious point of interest then randomly probe to investigate the detailed behaviour of your circuit Note that you can add fixed probes after a run has started but the run must be paused first 213 User s Manual There are currently 8 types of fixed probe to suit a range of applications The random probing method allows you to plot anything you like including device power FFTs arbitrary expressions of simulation results and X Y plots such
218. g Auto No change No change Auto scale Defined Defined Min 0 Max 1 X Axis Y Axis Lin Log Auto Specify whether you want X Axis to be linear or logarithmic If Auto is selected the axis X or Y will be set to log if the x values are logarithmically spaced For the Y axis it is also necessary that the curve values are positive for a log axis to be selected No Change Keep axes how they are Only relevant if adding to an existing graph Auto scale Set limits to fit curves Defined Set to limits defined in Min and Max boxes Axis Labels Sheet This sheet has four edit boxes allowing you to specify x and y axis labels as well as their units If any box is left blank a default value will be used or will remain unchanged if the axis already has a defined label Chapter 9 Graphs Probes and Data Analysis Using Random Probes in Hierarchical Designs Random probes may successfully be employed in hierarchical designs There are however some complications that arise and these are explained below Closed Schematics Read the following if you find situations where cross probing inside hierarchical blocks sometimes fails to function The names used for cross probing are stored in the schematic itself and are saved to the schematic file These netnames are not assigned until the netlist is created and this doesn t usually happen until a simulation is run A problem arises however if the schematic is not open I
219. g in above example if PARALLEL property were empty or missing then no output will be made at all The example above can be used for any two terminal component There must however be a PARALLEL property present on the symbol STEP lt STEP gt Used with SERIES and PARALLEL keywords Returns sequence number IF lt IF test action1 action2 gt If test resolves to a non zero value action will be substituted otherwise action2 will be substituted Typically test would be an expression enclosed in curly braces and For example the following implements in a somewhat complex manner a series connection of resistors This should actually all be on one line Chapter 4 Schematic Editor lt REPEAT line SSERIES lt REF R line lt if line 1 lt lt NODE 1 gt gt S REF line gt lt if line 3SERIES lt lt NODE 2 gt gt S REF line 1 gt VALUE gt gt Note that usually each action should be enclosed with lt and gt They can be omitted if the action does not contain any keywords If in doubt put them in IFD lt IFD propname action1 action2 gt If propname is present and not blank action will be substituted otherwise action2 will be substituted Example lt ifd value lt value gt 1 gt In the above if the property value is present it will be substituted otherwise the value P will be substituted JOIN lt JOIN prop_name index gt This can only be used with insta
220. g Tolerances To specify device match tolerances proceed as follows Select the components you wish to match to each other Use control key to select multiple components 7 Select menu item Monte Carlo Set Match Tolerances Enter the desired tolerance Chapter 12 Monte Carlo Analysis If using device tolerance parameters note that any absolute tolerance specified must be the same for all devices within the same lot Any devices with the same lot name but different absolute tolerance will be treated as belonging to a different lot For example if a circuit has four resistors all with lot name RN1 but two of them have an absolute tolerance of 1 and the other two have an absolute tolerance of 2 the 1 resistors won t be matched to the 2 resistors The 1 resistors will however be matched to each other as will the 2 resistors This does not apply to match tolerances It s perfectly OK to have devices with different match tolerances within the same lot Random Distribution The default distribution for device tolerances is Gaussian with the tolerance representing a 30 spread This can be changed to rectangular using two simulator options These are MC_ABSOLUTE_ RECT If set absolute tolerances will have a rectangular distribution MC_MATCH_ RECT If set matching tolerances will have a rectangular distribution Distributions can be specified on a per component basis or even a per parameter basis by using distribution functions in
221. g is the same as for classic but when superimposed pins are separated a wire is created to maintain the electrical connection 3 Orthogonal As grow wire but wires are edited in a manner so that they are kept at right angles as much as possible The default setting is Classic To change to a new setting proceed as follows 1 Select command shell menu File Options General 2 In schematic tab in the Edit Mode section select the mode of your choice Note that this change will not affect currently open schematic sheets Bus Connections SIMetrix provides the Bus Ripper symbol to allow the connection of busses To Add a Bus Connector 1 Select the menu Place Connectors Bus Ripper or popup Connectors Bus Ripper This will display dialog E Define Bus Ripper Ripper parameters Bus Name optional Start index 0 s End index 3 Aj Style Top diag v Enter a bus name if you require it 2 Start index and end index define the wires within the bus that you wish to connect to Suppose you were connecting to a data bus called DATA and it was 16 bits wide If you wish to make a connection to the 4 bits from DATA8 to DATA11 you would enter 8 and 11 for the start and end index respectively The bus ripper doesn t care about the size of the bus to which it is connecting 3 Choose an appropriate style This only affects the appearance of the symbol not its functionality 4 Press OK then place the sym
222. g wire regardless of what it is connected to In general we recommend that the option is left switched To change the smart wiring options select menu File Options General The two wiring options are in the section titled Wiring Manual Wiring Procedure If you have a three button mouse you can start a wire by clicking the middle button Clicking the middle button a second time will complete the wire and start a new one Click the right button to terminate wiring If you have a two button mouse you can start a wire by pressing F3 or double clicking the left button Single clicking the left button will complete the wire and start a new one Click the right button to terminate wiring Alternatively press the Wire button on the toolbar Z You can start a wire by single clicking the left button otherwise continue as described above Press the Wire button again to cancel this mode Edit Modes SIMetrix has three alternative edit modes that affect how wires are treated during move operations and also the behaviour when superimposed connecting pins are separated These are 1 Classic This is a basic rubberbanding mode where wires are fixed at one end and follow the component at the selected end When superimposed pins are Chapter 4 Schematic Editor separated no wire is created between them This is the method used for all SIMetrix version up to and including release 5 2 hence the name classic 2 Grow wire The wire editin
223. gress of the SIMPLIS simulation will be displayed Please refer to the SIMPLIS Reference Manual for more information about this display SIMPLIS can be aborted by pressing the Abort button in the progress window SIMPLIS cannot however be paused and resumed Plotting Simulation Results 66 Overview SIMetrix provides two methods of creating plots of simulated results The first approach is to fix voltage or current probes to the schematic before or during a run SIMetrix will then generate graphs of the selected voltages and or currents automatically The probes have a wide range of options which allow you to specify for example how the graphs are organised and when and how often they are updated The second approach is to randomly probe the circuit after the run is complete You can also do this during a run by pausing first With this approach the graph will be created as you point the probe but will not be updated on a new run You do not need to make any decisions on how you wish to probe your circuit before starting the run You can enter a circuit without any fixed probes run it then randomly probe afterwards Alternatively you can place say a single fixed probe on an obvious point of interest then randomly probe to investigate the detailed behaviour of your circuit Fixed schematic probes are limited to single ended voltages and currents and differential voltages The random probing method allows you to plot anything
224. he Location of the License Server 24 License Server Version sessirnir 24 Obtaining a License File eeeeeeeeeeeeeeeeeeees 25 Using the License Server ccceeeeeeseeteeeeeetees 26 Whiat ls Simetrixes 2 2 cccccticcecgecbeedecide aenieei 27 What is SIMPLIS 20 0 eee eeeeeeeeeeeesneeeeeeeeenneeeeenaeeeeenees 28 Why Simulate 2 eee ee esneeeeeeeeeeneeeeeeneeeseeeeensaeeeenaaes 29 System Requirement 0 0 0 ececeeeeeeeeneeeeeneeeeeneeeeeeeeees 29 Operating SySteM oo ee rererere 29 FAPAWAMC keete inarin itning detainee iai naniii aia 30 Recommended System eneren 30 Upgrade Notesin iaa aa 30 Upgrading from Version 4 5 30 Upgrading from Version 5 0 31 Chapter 2 Quick Start Examples and Tutorials Where are They 32 Simulation for the Novice 32 Tutorial 1 A Simple Ready to Run Circuit 33 Tutorial 2 A Simple SMPS Circuit eee 41 Tutorial 3 Installing Third Party Models ee 49 User s Manual Chapter 3 Chapter 4 Getting Started Simulation Modes SIMetrix or SIMPLIS eee 53 Using the Schematic Editor oo eee eeeeeeeeeeeeeee 53 Creating a Schematic 53 Circuit RULES cceccccsceccecceee centred ceee dicen gt deesdieeeneeeeetecetedeed 55 Cifcuit Stimulus 2 1i3 4 88 a a a E 56 Waveform Generatol cccccccecceceeeeeeceeeeeeeeeeneees 56 PWL SOUrCE AE EAE E ETET 57 Power Supply Fixed Current Source n 57 VERS OIT KE e EEIT 57 Univers
225. he absolute position of the reference cursor the absolute position of the main cursor and the difference between them respectively You can add additional text to these For 245 User s Manual 246 example if you changed label 1 to Pulse Start x1 the value displayed for the position of the reference cursor would be prefixed with Pulse Start lt You can use expressions relating constants and symbolic values enclosed by Expressions must be enclosed in braces and For example the expression 1 oxdiff will cause the difference value to be displayed as a reciprocal This is useful if you wanted to display a frequency instead of a period You can use any arithmetic operator along with many of the functions described in the script reference manual in these expressions Style Show Absolute Clear check box to disable display of the absolute positions of the cursors Show Difference Clear check box to disable display of relative positions Automatic Internal External Style of dimension Internal means that the arrows will always be displayed between the cursors External means they will always be displayed outside the cursors In automatic mode the style will change according to the spacing and position Note if you clear both absolute and difference you will only be able to restore the display of the dimension by switching cursors off then on again Font Select font used for re
226. he power of argument If the argument is greater than 709 016 an overflow error occurs 301 User s Manual 302 fft real string Vector to be processed String specifying window type Possible values are Hanning default and None Performs a Fast Fourier Transform on supplied vector The number of points used is the next binary power higher than the length of argument 1 Excess points are zero filled Window used may be Hanning default or None Users should note that using this function applied to raw transient analysis data will not produce meaningful results as the values are unevenly spaced If you apply this function to simulation data you must either specify that the simulator outputs at fixed intervals select the Output at interval option in the Choose Analysis dialog box or you must interpolate the results using the Interp function see page 305 The FFT plotting menu items run a script which interpolate the data if it detects that the results are unevenly spaced Use of these menus does not require special consideration by the user Further information on FFTs can be found on page 222 FIR real real real Vector to be filtered Filter coefficients Initial conditions Default all zero Performs Finite Impulse Response digital filtering on supplied vector This function performs the operation Yn Xn Co Xn 1 C1 Xn2 C2 Where x is the input vector argument 1 c is the c
227. he zero crossing If this is the case you can calculate the time from the zero crossing to the reverse peak using the values for IRM and dIf dt and so arrive at the value of Tr as shown above Chapter 5 Components Some data sheets do not give the value of IRM In these cases the best that can be done is to enter an intelligent guess Capacitance is the measured value at zero bias Unfortunately this is not always quoted in data sheets in which case you can either enter zero which may speed simulation times or enter an estimated value Of course an alternative would be to measure the capacitance of an actual device Notes of Soft Recovery Diode Model The soft recovery diode does not use the standard SPICE model but a new model based on work at the University of Washington Full details of the model can be found in the Simulator Reference Manual Subcircuits Overview Subcircuits are a method of defining a circuit block which can be referenced any number of times by a single netlist line or schematic device Subcircuits are the method used to define many device models such as op amps It is also the underlying mechanism of the hierarchical schematic entry system You don t need to know anything about subcircuits unless you wish to define you own device models perhaps to build up a library of tested blocks for general distribution If you just wish to enter your circuit in a modular manner hierarchical schematic entry is probably the
228. hematic in the same way as you would one created by SIMetrix Installing PSpice Libraries for Use with SIMetrix You can install PSpice symbol libraries in the same way as SIMetrix symbol libraries This will make the symbols available for use with SIMetrix Note that the schematic translator only uses symbols in the PSpice libraries specified using the procedure described above What the Translator will do 1 The translator will convert symbols parts and wires and display them in a manner that is as close as reasonably possible to the original schematic 2 It will convert any TEMPLATE properties to the SIMetrix format while preserving the original PSpice template under a different name 3 It will copy where possible any simulator commands to the F11 window 4 Hierarchical symbols will be appropriately converted but the underlying schematics need to be converted separately and saved in SIMetrix format 5 Translated symbols will be copied to PSPICE SXSLB in the SymbolLibraries directory By default this library is not installed If you do install it see Symbol Library Manager these symbols can then be used in SIMetrix schematics Limitations The translator has the following limitations 1 It cannot convert busses 2 Boxes text boxes free text and embedded graphics are not supported 3 Pin attributes are not supported 4 Hierarchical blocks are not supported but hierarchical symbols are To use hierarchical blocks u
229. hen press the rotate button key to rotate in situ To mirror a component or block through the y axis press the mirror toolbar button or F6 key To flip a component or block mirror about x axis press Flip button or press shift F6 Wiring If you have a three button mouse you can start a wire by clicking the middle button Clicking the middle button a second time will complete the wire and start a new one Click the right button to terminate wiring If you have a two button mouse you can start a wire by pressing F3 or double clicking the left button Single clicking the left button will complete the wire and start a new one Click the right button to terminate wiring Alternatively press the Wire button on the toolbar Z You can start a wire by single clicking the left button otherwise continue as described above Press the Wire button again to cancel this mode Disconnecting Wires Press the shift key then select area enclosing the wire Press delete button Chapter 3 Getting Started To Move Items Disconnected Select items then schematic menu Edit Detach Move items to desired location then press left mouse key You can rotate flip mirror the items see above while doing so To Copy Across Schematics Select block you wish to copy Choose menu Edit Copy In second schematic choose Edit Paste Multiple Selection Individual items which do not lie within a single rectangle can be selected by holding down the control key
230. high a value so we will try 2 2pF To change the component s value proceed as follows 1 Select C1 To do this just left click on it 39 User s Manual 40 2 Either press F7 or right click in the schematic and select popup menu Edit Part You should see the following dialog box appear A Choose Component Value Device Yalue Base 1 sj Decade 1n jal Result Tri s Series O ES E12 O E24 Initial Conditions Open circuit Enable For Analysis O Initial voltage Op Transient Cancel Parameters You can type the new value in directly in the Result box or you can select a value using the mouse alone with the up and down arrow buttons Leave the Initial Condition setting at its default Open Circuit 3 Now re run the simulation This is the result you should see With R6 add d With R6 anfi C1 added Amplifier Output mV 0 50 100 Time nSecs 150 200 250 300 350 400 50nSecs div The blue curve is the latest result This is now a big improvement on our first attempt We will now round off tutorial 1 by introducing AC analysis AC analysis performs a frequency sweep over a specified frequency range To set one up follow these instructions Chapter 2 Quick Start 1 In the schematic window select the menu Simulator Choose Analysis This is what you will see El Choose Analysis sti B Transient AC DC No
231. holly enclosed by the selection box Unselecting Place the cursor in an empty area and press left mouse key Unselect Items Within a Rectangle You can unselect an area of schematic enclosed by the selection box Use menu Edit Unselect Rectangle To Increment Decrement a Component Value Select component then press shift up or shift down respectively This only works with resistors capacitors and inductors To Change a Component Reference Select component s then press F8 or select schematic menu Edit Change Reference Enter new reference To Correct a Mistake Press the Undo button By default you can backtrack up to ten operations but this can be changed with File Options General If you want to undo the undo operation select the schematic popup or fixed menu Edit Redo menu item 73 User s Manual 74 To Add Text To a Schematic Select the popup menu item Edit Add Free Text This opens a dialog box prompting you for the text to be entered After entering text and closing box you can then position the text where you require using the mouse To Change Text Already Entered Select the text then press F7 and enter the new text To Hide A Component Value Select popup menu item Hide Show Value Zoom Area Press a button on schematic Drag mouse to zoom in on selected area Zoom Full Fit to Area Select popup Zoom Full or press HOME key to fit whole schematic in current window size Zoom Out
232. hs PSpicelniPath Text Path of PSPICE INI file Option needed for the PSpice dialog Schematics translator RebuildConfig Boolean Default true No See Auto Configuration Options on page 346 RepeatPlace Text Default Toolbar Options Controls when schematic dialog placement is repeated Possible values Always Toolbar toolbar symbols only and Never 339 User s Manual 340 Name SchematicEditMode SchematicMoveMode SchematicReadOnly SchemDoubleClickScript ScriptDir SimDataGroupDelete Type Text Text Boolean Text Text Text Description Default NoSnap Schematic behaviour when double clicking If set to Classic a wire is started If set to NoSnap a script defined by SchemDoubleClickScript is called Standard behaviour is to edit a component if mouse is located inside one Default ClassicMode Controls wiring behaviour with schematic move operations Values are ClassicMove GrowWire and Orthogonal See Edit Modes on page 76 for details Default false If set all schematics are opened in read only mode Default on_schem_double _ Click ne Script that is called when a double click action is detected in the schematic Only active if SchematicEditMode NoSnap Directory used to search for scripts and symbol files if not found in the current directory Changes to this option do not take effect until next session Default Never S
233. ic symbol to use nor what category it should be in the parts browser SIMetrix is able to determine this for itself if the device is implemented using a MODEL control as all MODELs refer to a particular type of device NPN NMOS Diode etc Devices implemented as subcircuits however remain a problem as there is nothing in a SUBCKT definition which tells SIMetrix what the device is For example a three terminal regulator and a power MOSFET use identical syntax SIMetrix can t tell the difference from the syntax alone To resolve this SIMetrix is shipped with a database of known part numbers providing a named schematic symbol component category and if relevant a pin mapping order If the part is in the database no further action is required by the user and the part will appear in the browser under the correct category and select the correct symbol If the model is not in the database and has 2 or 3 terminals then SIMetrix will attempt to determine the type of device by performing some tests on the model using simulation If this process is successful SIMetrix will choose an appropriate schematic symbol without further action required If SIMetrix cannot determine what the device is then in order to use the device on a schematic you will need to provide the association information You will be prompted for this information when you place a part on the schematic for the first time and this is often the most convenient method However there is al
234. ic Examples SIMPLIS Manual_Examples Example1 examplel sxsch We will set up the system to repeat the analysis three times while varying R3 Proceed as follows 1 First we must define R3 s value in terms of an expression relating to a parameter To do this select R3 then press shift F7 Enter the following r3_value r3_ value is an arbitrary parameter name You could also use R3 2 Select menu Simulator Select Multi step Chapter 8 SIMPLIS Analysis Modes 3 Enter r3_ value for Parameter Name and set Start value to 20 Stop value to 100 and Number of steps to 3 This should be what you see aA Define SIMPLIS Multi Step Analysis Sweep mode Step parameters Parameter Start value 20 j Monte Carlo Stop value 100 aj x Number of 3 ai Parameters steps Parameter 3 value Decade Group curves name Linear List Define List 4 Press Run The analysis will be repeated three times for values of r3_ value of 20 60 and 100 The resistor value R3 is defined in terms of r3_value so in effect we are stepping R3 through that range In most cases you will probably want to step just one component in a similar manner as described above But you can also use the parameter value to define any number of component or model values If you now run a normal single analysis you will find that SIMPLIS reports an error as it is unable to resolve the value for R3 This can be overcome by
235. ications such as creating series and parallel combinations How Template Properties are Evaluated Template properties are processed in two passes In the first pass the property names enclosed by are substituted while keywords and expressions pass through untouched In the second pass keywords and expressions are processed and the character is treated literally This makes it possible to use property values in expressions and the control values for the multi line keywords For example SMODELZS REF lt nodelist gt SVALUES L L W W AD W 0 5u if L lu W 0 5u MODEL M REF Q23 and VALUE N1 this would resolve to the following after the first pass MS Q23 lt nodelist gt N1 L lu W 0 5u AD 0 5u 0 5u 107 User s Manual 108 The second pass would then be able to evaluate the expression and resolve lt nodelist gt see below The value of AD will be calculated according to whatever W is set to This is an alternative method of setting MOSFET area and perimeter values The method used with the standard symbols is different in order to remain compatible with earlier versions Note that if the property value contains any of the special characters lt gt these will be treated literally So if for example a property value was tailres no attempt would be made to evaluate tailres in the second pass Keyword Summary The keywords available are summarised in the following table and ex
236. ified This introduces a potential problem in that once back annotated initial conditions are applied you will no longer be able to modify individual initial conditions within a hierarchical block You will only be able to edit them on the top level device using the Edit Additional Parameters menu You will be able to use initial conditions defined within a hierarchy or subcircuit if you first disable top level initial conditions using the Initial Conditions Disable menu This will of course disable all initial conditions specified at the top level To disable initial conditions for a single hierarchical block use the Edit Properties menu to set the USEIC property to 0 Note that the Enable and Disable menus will reset this property 211 User s Manual Chapter 9 Graphs Probes and Data Analysis Overview The basics of how to create graphs of your circuit s signals were explained in Getting Started on page 53 This chapter provides a full reference on all aspects of probing and creating graphs Elements of the Graph Window Main Window Toolbar HA PSU Waveforms Selected Joe Fle Echt Cursors Annotate Curves Axes View Measure Plot Handle Use this to undock BRA Qa QA K E SALLE Re panel It can be positioned m ESP 1 on another edge or float free Curve Legend mosey Legend Panel tran2 I L3 P Y1 Selected Y Axis i v1 Y Axis _ i 15 10
237. ify a different image size use next option 4 Bitmap specify image size png jpg bmp As 3 above but you must explicitly define the image resolution in pixels You will be prompted for this when you close the file selection dialog box Note that schematics always maintain their aspect ratio so the final image size may differ from what you specify The actual image will always fit within the X and Y values you give Exporting to Earlier Versions of SIMetrix Schematics created with SIMetrix version 5 3 or earlier can be read by all SIMetrix versions from and including version 4 1 But note that changes in symbol design do introduce some difficulties that may need special treatment In particular capacitor and inductor symbols used in version 4 2 and later do not work correctly with version 4 1 without modification To export to versions 2 5 to 4 0 select the menu File Save As then in the Save as type box select Schematic Release 2 5 4 0 Format ASCII format SIMetrix schematics are usually saved in a binary format This is fast compact and can be read by earlier versions From version 5 0 a new ASCII format was introduced The format used is fully documented allowing the development of translators to other formats Also there are some editing operations that are easier performed on an ASCII file than with the graphical editor For example changing a symbol name is very difficult with the schematic editor as you have to delete an
238. ii ee a aes 183 Noise Analysis asses cscceseceeessenctestess tescecenal coeescebd aaseesncttese 183 Setting up an AC Noise analySis eee 183 Plotting Results of Noise AnalySis 06 184 Examples 1iicc cii skies aie anita ea eae 185 E AE EE tds scxtasiosabates tases 186 Real Time NoiSe sironnan 187 Setting Up a Real Time Noise Analysis 187 Transfer FUNCOM sasse eiieeii pairin anina 188 Setting up a Transfer Function Analysis 188 Plotting Transfer Function Analysis Results 189 Example cc a ene a Nai a N 189 POlG ZONO 253 ceiiscacweseuennesteonteshcs adp eard fhineag 191 Setting up a Pole zero Analysis ceeeeeeeeees 191 Viewing ReSults cccccecceceeeeeecteeeeeeseeeeeeeeees 191 Examples iioun Ae ee 191 SOMISIENVIEY EEEE cnc da tease aceasta svucdegdtce peaches TETT 191 Setting up a Sensitivity Analysis 0 ee 192 Simulator Options ee eeeeeeeeeeeeeeeeeeneeeseeeeeenaeeeeeaes 192 Setting Simulator Options 0 ee eeeeeeeeeereees 192 Multi step Analyses 00 0 eeeeeeeceeeesneeeeeeeeeeneeeensaeeeeenaees 194 Setting up a Multi step Analysis 0 000 eee 195 Example Tieri cae eas 196 EXAMpPle 2 ser erdene ener iee e aeee Eaei 197 Safe Operating Area Testing 198 OVEVIEW vi iaieiiea een eai oain 198 Table of Contents Defining Simple Limit Tests eeeeeeeeeeeeeee 198 Advanced SOA Limit Testing 199 Chapter 8 SIMPLIS Analysis Modes
239. inding it Chapter 7 Analysis Modes Note that the reduced precision can also reduce the accuracy at which a steady state is found and often a settling time is required after the fast start period Restarting a Transient Run After a transient analysis has run to completion that is it has reached its stop time it is still possible to restart the analysis to carry on from where it previously stopped This feature is not available with all versions of the product contact sales for details To restart a transient run 1 Select the menu Simulator Restart Transient 2 In the New Stop Time box enter the time at which you wish the restarted analysis to stop Press Ok to start run See Also TRAN in Simulator Reference Manual Transient Snapshots Overview There is often a need to investigate a circuit at a set of circuit conditions that can only be achieved during a transient run For example you might find that an amplifier circuit oscillates under some conditions but these conditions are difficult or impossible to create during the bias point calculation that usually precedes a small signal AC analysis Transient snapshots provide a solution to this problem The state of the circuit at user specified points during a transient run may be saved and subsequently used to initialise a small signal analysis The saved state of the circuit is called a snapshot Snapshots can be created at specified intervals during a transie
240. ine List Group Curves Curve traces plotted from the results of multi step analyses will be grouped together with a single legend and all in the same colour For Monte Carlo analysis this is compulsory for other analyses it is off by default 195 User s Manual Parameters The parameters required vary according to the mode as follows Mode Parameters Device Device name e g V1 Parameter Parameter name Model Parameter Model name Model parameter name Temperature None Frequency not DC or transient None Monte Carlo None Example 1 Refer to circuit on page 186 In the previous example we swept the tail current to find the optimum value to minimise noise for a 1K source resistance Here we extend the example further so that the run is repeated for a range of source resistances The source resistance is varied by performing a parameter step on sourceR Here is what the dialog settings are for the multi step run fl Define Multi Step Analysis K Sweep mode Step parameters Device Start value 1k Aj Parameter Stop value 100k al Model parameter Steps per decade 10 3 Temperature Decade C Group curves O Frequency O Linear Monte Carlo O List Snapshot Define List Parameters Device name Parameter name sourceR This does a decade sweep varying sourceR from 1K to 100k with 2 steps per decade This is the result we get 196 Chapter 7 Analysis Modes sourceR 100040 sourc
241. ings on page 324 for more information User constants are defined in the Locations section of the file Currently these must be added by hand using a text editor The format used is as follows Locations symbol definitions Where symbol_definitions is any number lines of the form symbolname symbolvalue symbolvalue may be any sequence of characters that are valid for a system path name and may contain spaces There is no need to enclose it in quotation marks even if the 321 User s Manual 322 value contains spaces Nested definitions to any level are permitted That is symbolvalue may also itself use other symbolic constants Recursive definitions won t raise an error but will not be meaningful UNC paths e g server c project may be used for symbolvalue Comments may be added to the project file prefixed with a semi colon Configuration File Example The following shows examples of symbolic path name definitions in the configuration file Lines such as these may be placed anywhere in the file but we recommend that they are placed at the end 7 Project file Locations Project c Projects projl Cells PROJECT Cells Using Symbolic Names Symbolic path constants may be used in the applications listed below In all cases a mechanism called automatic path matching is used which means that to use symbolic paths all you need to do is define the values in the project file then carry on working as before The
242. initial value U and a Model property which must have the value X Placing Symbol If the schematic containing the block has never been saved untitled in caption bar you must save it now This is so that the schematic has a title This step is only necessary if the schematic has never been saved before Select either Hierarchy Place Component Full Path or Hierarchy Place Component Relative Path The first references the component file using a full file system path name while the second uses a path relative to the parent schematic See Placing Full vs Relative Path on page 82 for more details Select the SXCMP file you used to save the symbol in the above paragraph Note that you will see the warning message Component module ports in underlying schematic do not match symbol pins displayed in the command shell This warning may be ignored at this point Creating Schematic for Block 1 Select the symbol whose schematic you wish to define then select schematic menu Hierarchy Descend Into Note the symbol must have been saved as a component as described above 2 Anew schematic sheet will be opened with a number of module port symbols already placed These will be named according to the pin names of the block You must use these to make connections to the outside world Bottom up method Creating Schematic 1 Open or draw schematic It must have at least one Module Port symbol on it To place
243. ircuit using a frequency sweep 1001 40n N 20n T gt 2 k i 101 zZ 3 gt f 1 1 10 100 1k 10k 100k 1M 10M 100M 1G Frequency Hertz 185 User s Manual 186 Example 2 Noise with a Parameter Sweep In the following circuit we wish to find the optimum value of tail current for a source impedance of 1K To do this we sweep the parameter taili which is used to set the current as well as the values for R1 R2 R3 and R4 As can be seen from the graph about 300A would seem to be best The noise analysis was setup with the following parameters Sweep parameter taili from 1p to 10m 25 points per decade Output node VPos Reference node VNeg Input source V3 sourceR 1000 set with PARAM control 1 taili 5 R4 VPos X sourceR Re E 1 taili 50 R2 OsuB The result Input Noise V rtHz Chapter 7 Analysis Modes 100 Input referred noise while sw eeping tail current Frequency 1K sourceR 1K 40n 20n n n l ip TOP 100p im 70m 2 taili Real Time Noise This is an extension of transient analysis rather than a separate analysis mode When activated real time noise sources are added to all noisy devices with a magnitude and frequency distribution calculated using the same equations used for AC noise analysis This allows noise analysis to be performed on sampled
244. is Graph Options Sheet Allows you to control where the curve for the probed signal will be placed A Define Curve Define Curve Axis type Use new grid Digital Axis Graph Options Axis Scales Axis Labels Graph options Add to selecte New graph sheet New graph window Axis Type Select an appropriate axis type Note that you can move a curve to a new axis or grid after it has been plotted See Moving Curves to Different Axis or Grid on page 237 Auto select Use Selected Use New Y axis Use New Grid Digital Axis Select an appropriate axis automatically See AutoAxis Feature on page 237 Use currently selected y axis Create a new y axis alongside main one Create a new grid stacked on top of main axis Create a new digital axis Digital axes are placed at the top of the window and are stacked Each one may only take a single curve As their name suggests they are intended for digital traces but can be used for analog signals if required 231 User s Manual 232 Graph Options Add To Selected Add curve to currently selected and displayed graph sheet New Graph Sheet Create a new graph sheet within current graph window New Graph Window Create a new graph window Axis Scales Sheet Allows you to specify limits for x and y axes Fy Define Curve x Define Curve Axis Graph Options Axis Scales Axis Labels K Aris Y Axis Olin Log Auto O Ln O Lo
245. is the start wire default is 0 and B is the final wire Note that if you edited an existing symbol to add a bus connection you may not see this label If so select the component then menu Hierarchy Update Bus Connections 2 Press F7 then enter the new offset and OK You will see the label change accordingly For example suppose the bus has 8 wires as defined in the child schematic To begin with the label will be 0 7 and will therefore connect to bus wire 0 to 7 If you change the offset to for example 4 the label will change to 4 11 meaning that the connection will now be made to wires 4 to 11 Changing a Non bus Connection to a Bus Connection 1 In the child schematic change the Module Port to a Module Bus Port and edit as appropriate 2 Inthe parent schematic select the block then menu Hierarchy Update Bus Connections This will update the schematic to show the bus connection on the hierarchical block Changing the Size of a Bus Connection 1 In the child schematic select the appropriate Module Bus Port 2 Press F7 and enter the new size as required 3 In the parent schematic select the block then menu Hierarchy Update Bus Connections 83 User s Manual 84 Global Nets You can access any net at the top level of a hierarchy using a terminal symbol and prefixing the name with For example suppose you have a net at the top level called VCC You can access this net at any level of the hierarchy without h
246. is will display Edit Potentiometer K Parameters Resistance 10k Wiper Position 0 5 Note You can also use shift UP and shift DOWN to adjust the wiper position Increment decrement 50m step size C Run simulation after position change Enter Resistance and Wiper position as required Check Run simulation after position change if you wish a new simulation to be run immediately after the wiper position changes Chapter 5 Components The potentiometer s wiper position may also be altered using the shift up and shift down keys while the device is selected Edit Inc dec step size to alter the step size used for this feature Lossless Transmission Line Select from menu Place Passives Trans Line Lossless or press hot key T Editing in the usual way will display a Edit Device Parameters x Characteristic Impedance 50 Delay 50n Relative Tolerance 1 Absolute Tolerance 1 i Enter the Characteristic Impedance Z0 and Delay as indicated Lossy Transmission Line Select from menu Place Passives Trans Line Lossy RLC Editing in the usual way will display fa Edit Device Parameters x Resistance per unit length 100m is Inductance per unit length 250n 4 Capacitance per unit length 100p 3 Length 1 a Relative tolerance 1 is Absolute tolerance 1 aj Lossy lines must be defined in terms of their per unit length impedance characteristics Currently only
247. ise IG Options SOA M Transient Transient parameters oac Stop time 104 i CI DE Sweep C Noise Data output options eee C Transfer function Start data output 0 z Default O DCOP PRINT step 200r Default Output all data Output at PRINT step Real time noise C Enable realtime noise Define Monte Carlo and multi step analysis C Enable multi step Selected mode None Define Snapshots Advanced Options 2 Click the check box titled AC and uncheck the Transient check box The details of the AC sweep have already been set up To view them click the AC tab at the top of the box 3 Run the simulation A new graph sheet will open within the same window as the existing ones Tutorial 2 A Simple SMPS Circuit In this tutorial we will simulate a simple SMPS switching stage to demonstrate some of the more advanced plotting and waveform analysis facilities available with SIMetrix 41 User s Manual i a ESR_C1 80m D2 R3 V1 murd310 as 3 9 ALG 150u Ji o E Output L1 IRF750 1 e K m R2 Q1 v2 x Pulse 0 5 0 50n 50n 1 95u 5u You can either load this circuit from EXAMPLES Tutorials Tutorial2 see Examples and Tutorials Where are They on page 32 or alternatively you can enter it from scratch The latter approach is a useful exercise in using the schematic editor To do this follow these instructions 1 2s 42 Pl
248. iven 308 range minidx real complex Returns index of vector where 308 smallest value is held 299 User s Manual 300 Function name Description Page no Minima real real string Returns locations of minima of 308 specified vector norm real complex Returns argument scaled so that 309 its largest value is unity ph phase real complex Returns phase of argument 309 phase_rad real complex As ph but result always in 309 radians Range real complex real real Returns range of vector 309 re real real complex Return real part of argument 309 Ref real complex Returns reference of argument 309 Rms real Returns accumulative RMS value 310 of argument RMS 1 real real real Returns RMS of argument over 310 specified range rnd real Returns random number 310 RootSumOfSquares real real Returns root sum of squares of 310 real argument over specified range sign real Return sign of argument 310 sin real complex Sine 310 sqrt real complex Square root 310 tan real complex Tangent 311 Truncate real real real Returns vector that is a sub 311 range of supplied vector unitvec real Returns vector of specified length 311 whose elements are all 1 vector real Returns vector of specified length 311 with each element equal to its index XFromy real real real Returns array of values 311 specifying horizontal locations where specified vector crosses given y value YFromX real real real Returns array of
249. jority of messages including errors and warnings are displayed here The window can be scrolled vertically with the scroll bar You can copy a line of text from the message window to the command line by placing the cursor on the line and either double clicking the left mouse key or pressing the Insert key Up to 2000 lines of messages will be retained for viewing at any time Menu Reference For complete documentation on menu system please refer to the on line help The menu reference topic can be viewed by selecting the menu Help Menu Reference Keyboard The following keys definitions are built in They can all be redefined using the DefKey command see DefKey on page 290 or short cut with DefMenu command Key Unshifted Shift Control Shift Control A Place 2 input Ascend one level AND schem B Place fixed voltage probe Cc Place capacitor D Place diode E Place voltage controlled voltage source F Place current controlled current source Place ground H Place module port Place current source Place D type flip flop Place digital ground Place digital inverter Copy schem Copy to clipboard graph Duplicate schem Descend into block schem Browse Parts Show current in pin 285 User s Manual 286 Key Unshifted Shift Control Shift Control J Place N JFET K Place P JFET L Place ideal inductor M Place NMOS Place bias transistor marker N Place NPN Plac
250. kes it possible to use SIMetrix to graph data generated by other applications such as a spreadsheet This can be useful to compare simulated and measured results There are two alternative formats The first is simply a series of values separated by white space This will be read in as a single vector with a reference equal to its index The second format is as follows A text data file may contain any number of blocks Each block has a header followed by a list of datapoints The header and each datapoint must be on one line The header is of the form reference_nameydatal_name ydata2_name Each datapoint must be of the form reference_valueydatal_value ydata2_value The number of entries in each datapoint must correspond to the number of entries in the header The reference is the x data e g time or frequency Example Time Voltagel Voltage2 0 4 5396 4 6916 le 09 4 5397 4 6917 2e 09 4 5398 4 6917 4e 09 4 54 4 6917 8e 09 4 5408 4 6911 1 6e 08 4 5439 4 688 3 2e 08 4 5555 4 6766 6 4e 08 4 5909 4 641 le 07 4 6404 4 5905 1 064e 07 4 6483 4 5821 If the above was read in as a text file using OpenGroup text a new group called textn where n is a number would be generated The group would contain three vectors called time Voltage and Voltage2 The vectors Voltage and Voltage2 would have a reference of Time Time itself would not have a reference To read in complex values enclose the real and imaginary par
251. key down while doing so You can do this for a single symbol or for an entire category Note that when copying to a new library the symbol retains its user name and internal name There will therefore be duplicates installed unless they are renamed Deleting Symbols To delete a symbol select it then press Delete or the right click popup menu of the same name You can also delete an entire category in the same way Renaming Symbols Select a symbol then press F2 or the right click popup menu Rename You can also rename a category in the same way Note that this only renames the user name of the symbol There is no method of changing the internal name other than making a copy with a new name then deleting the original Creating a New Category To create a new category select the parent category where you wish it to be placed then press Create or the popup menu of the same name In the dialog that opens select the Category button and enter the new name Chapter 4 Schematic Editor Creating a New Symbol Select the category where you wish the symbol to be placed then press Create or the popup menu of the same name Enter the desired user name An internal name will be automatically entered as you type in the user name This can usually be left alone The symbol created will be empty Use the symbol editor to define it You can call this directly by pressing the Edit button Note that this will close the library manager dialog
252. lation for each SOA device will be reported In full output mode all violations are reported 4 In Results to choose where you would like the results reported Note that writing results to the message window is a time consuming operation and it is recommended that you should not select this if you are expecting a large number of violations Running Simulation Run the simulation in the normal way If there are any violations the results will be reported in the location or locations specified in the Results to section Advanced SOA Limit Testing The simulator control SETSOA allows much more sophisticated definitions for SOA limits In particular you can define limits for all devices belonging to a specified model Suppose that you are using a BJT model that has a Vcb limit of 15V While you could place a differential voltage watch device across each instance of this model this would be time consuming and error prone Instead you can define a single SETSOA control that refers to the model name of the device The simulator will then automatically set up the limit test for every instance of that model You would usually enter a SETSOA control in the schematic editor s F11 window See Manual Entry of Simulator Commands on page 65 for details For details of the SETSOA syntax please refer to the Simulator Reference Manual section titled SETSOA 199 User s Manual It is also possible to set up an SOA specification for
253. le Overshoot Peak Peak Peak Rise Time RMS aa vv You should see a value of about 2 8W displayed This is somewhat more than the 517mW average but is still well within the safe operating area of the device However as we noted earlier the inductor is ideal and does not saturate Lets have a look at the inductor current 1 Select schematic menu Probe Current in Device Pin New Graph Sheet 2 Left click on the left pin of the inductor L1 This is what you will see 46 Chapter 2 Quick Start L1 P A 0 0 2 0 4 0 6 0 8 1 Time mSecs 200uSecs div This shows that the operating current is less than 1 5A but peaks at over 6A In practice you would want to use an inductor with a maximum current of around 1 5 to 2A in this application otherwise it would be over designed and therefore over expensive We will now replace the ideal component with something closer to a real inductor 1 Delete L1 2 Select schematic menu Place Magnetics Saturable Transformer Inductor A dialog box will be displayed See picture below Select 0 secondaries then enter 34 in the turns edit box Next check Select Core Type Select EFD10 3F3 A25 This is part number for a Philips ferrite core This is what you should have 47 User s Manual A Define Saturable Transformer Inductor Configuration Define windings Primaries 1 4 Select winding Primary tums 34 Al Secondaries 0 A Ra
254. le schematics and generally the user must have write access to them It is also desirable for the user to have exclusive access If one or other of the conditions above don t apply then you can either 1 Install SIMetrix in non administrator mode and logged in as the end user In this case SIMetrix will install to a location exclusive to that user and to which he or she will have write access OR 2 Install in administrator mode and make a copy of the example files to the directory My Documents SIMetrix After SIMetrix first starts you should delete the Examples short cut that is automatically created in the My Documents SIMetrix directory Other potentially user editable files also exist in support symbollibs and support models Although these files can be edited by the user our general recommendation is that they remain unchanged There are facilities within the program to edit symbols and models without editing the standard files Chapter 1 Introduction Installation Linux Version Currently SIMetrix for Linux has to be installed manually but the procedure is nevertheless straightforward Before proceeding make sure you are using a supported distribution See System Requirements on page 29 for details To Install from CD Insert and mount CD The following assumes that the CD is mounted at mnt cdrom Proceed as follows 1 Become root 2 ed usr local 3 Extract the simetrix tar file tar xf
255. le route In manual mode you place each wire segment individually in exactly the locations you require You don t need to change global settings to select the mode you desire the procedures for each mode are different and so you can freely switch between them from one wiring operation to the next However in most applications you won t need to use the manual wiring method The smart wiring method can still be used to enter wire segments one by one simply by selecting start and end points that have an obvious straight line route The fundamental difference between smart and manual is that smart mode will a ways route around obstacles such as existing wire terminations or whole symbols In manual mode the wire will always go exactly where you take it even it crosses existing connections or passes through existing symbols Smart Wiring Procedure 1 Initiate smart wiring by bringing the mouse cursor close to either an unselected symbol pin or an unselected wire end As you do this you will notice that the cursor changes shape to depict a pen symbol 2 Click the left button press and release to mark the starting point of the wire connection 3 Move the cursor to the destination point This may be anywhere on the schematic not just at a wire end or symbol pin 75 User s Manual 76 If there is a viable route from the start point to the destination point SIMetrix will locate it and draw the wire route Smart Wiring Notes
256. le to change to a black background if this is preferred To do this select menu File Options Background Colour This will change the schematic symbol and graph windows to use the background colour selected Note that in order to use a black background the various graphical elements e g fonts and grids that need to contrast with the background will also need to have their colour changed The above menu will deal with this automatically but be aware that these changes will override any previous colour changes that you may have made User Defined Key and Menu Definitions The menu system and most of the keyboard are user definable In principle it is possible to define completely new menus which bear no similarity with the built in menus A more normal use of menu and key redefinition would probably be to add a special function or perhaps to delete some unused menus Menus are defined using the DefMenu command and keys can be defined with the DefKey command Unless you only wish to make a temporary definition it is best to place DefMenu and DefKey commands in the start up script so that they are automatically defined for all future sessions Key definitions may be context sensitive That is the definition is dependent on which type of window is currently active See DefKey command page 290 for more details The commands ListStdMenu and ListStdKeys list to a file the definitions for the built in menu and key definitions These can be
257. lete press OK The symbol will now be in the master library and you will see it listed in the Place From Symbol Library dialog box Graphically Editing Generated Symbols You can subsequently edit a generated symbol with the graphical editor but once you have done so you will not be able to modify it in the symbol generator In practice this is not usually a cause for concern The graphical editor can say add a pin or change the pin order as quickly as the symbol generator Only if you wish to vastly change the pin configuration of a symbol will it be advantageous to use the symbol generator Graphical Symbol Editor Notes The graphical symbol editor shares much in its operation and layout with the schematic editor For this reason it is recommended that before learning how to use the symbol editor you become competent in the operation of the schematic editor In some parts of the following sections the explanations assume that you are already familiar with the schematic editor Symbol Editor Window The following diagram shows the main elements of the symbol editor Enter draw Undo Duplicate Cut Rotate Mirror Flip Zoom Box out in segment mode untitled cog File Edit Property Pin Arcs o arcs and circles snap to 9 fh XG i BTA QQ A these More minor grid points come in to view with higher magnifications Minor grid point Lines Major grid point Device pins always snap to these
258. line and can also be accessed from scripts for further analysis IMPORTANT Sensitivity analysis is an unsupported mode This means that we cannot provide assistance in its use nor will we be able to resolve any problems found with it We may withdraw Sensitivity analysis from future versions of the product Setting up a Sensitivity Analysis Place a control of the following form in the F11 window SENS V nodename refnodename sourcename nodename Output node to which sensitivities are calculated refnodename Reference node Ground if omitted sourcename Voltage source to measure output current to which sensitivities are calculated Simulator Options 192 The simulator features a large number of option settings although fortunately the vast majority can be left at their default values for nearly all applications A few option settings can be set via the Choose Analysis dialog box and these are described in the following sections The remainder can be controlled using the simulator s OPTIONS control details of which may be found in the Simulator Reference Manual Setting Simulator Options 1 Select menu Simulator Choose Analysis 2 Select Options tab The following will be displayed E Choose Analysis Chapter 7 Analysis Modes j x Transient AC DC Noise TF Options SOA Transient J Tolerances Relative tolerance 1m Curent tolerance 1p Voltage tolerance 1u Circ
259. ll as 6 different modes there are 3 different sweep methods which can be applied to all modes except Monte Carlo These are Linear Chapter 7 Analysis Modes Decade List The simulator also offers an Octal sweep method but this is not supported by the Choose Analysis Dialog Setting up a Multi step Analysis Define Transient AC DC Noise or Transfer Function as required then check Enable Multi step and press Define button For transient DC analysis you will see the following dialog box Other analysis modes will be the same except that the frequency radio button will be enabled e Define Multi Step Analysis Sweep mode Step parameters Device Start value 1k Parameter Stop value 2k Model parameter Number of steps 19 Temperature Decade Group curves Frequency Linear Monte Carlo List Snapshot Define List Parameters Device name Cancel Parameter name Help Enter parameter as described below Only the boxes for which entries are required will be enabled In the above example only the Number of steps box is enabled as this is all that is required for Monte Carlo mode Sweep Mode Choice of 6 modes as described above Step Parameters Define range of values If Decade is selected you must specify the number of steps per decade while if Linear is specified the total number of steps must be entered If List is selected you must define a sequence of values by pressing Def
260. ln 1 0 will give the answer 0 3 1415926535897931 jm An error will always occur if both real and imaginary parts are zero Using In with AC Analysis Data See notes under log10 function below log10 real complex log real complex Returns log to base 10 of argument In general we recommend using log10 rather than log Software products of all types vary in their interpretation of log Some treat it as log to the base 10 and others treat it as log to the base e By using log10 there will never be any doubt Using log10 with Negative or Complex Values See notes above under In function Chapter 11 Command and Function Reference Using log10 with AC Analysis Data The data output by the simulator when running an AC or TF analysis is complex As described in Using In with Negative or Complex Values above all SIMetrix logarithm functions correctly handle complex arguments and return a complex value This means that the following expression to calculate dB will not produce the expected result 20 log data where data is a value produced by an AC analysis simulation What you should do is 20 1log mag data The mag function will convert the complex data to real values which is actually what is intended Better still use db data This is equivalent to 20 log mag data Note that the graph system will always plot the magnitude of complex data But any expression presented for plotting will be ev
261. lue with certain special characters and words substituted Text enclosed by lt and gt are keywords and have a special meaning Text enclosed with is substituted with the value of the property whose name is enclosed by the character Finally text enclosed by curly braces and will be treated as an expression and will be evaluated Each of these is described in more detail in the following sections Property Substitution Any text enclosed with is substituted with the value of the property whose name is enclosed by the character So REF would be substituted with the value of the ref property Expressions Text enclosed by curly braces and will be treated as an expression and will be evaluated Note that property substitutions are performed before expressions are evaluated so the result of an expression can depend on any combination of property values If the attempt to evaluate the expression fails the result will be empty No error message will be reported Keywords Any text enclosed by lt and gt represents a keyword The keyword along with the lt and gt will be substituted according to the keyword as defined in the following table There are two types of keyword simple and compound Simple keywords are just a single word whereas compound keywords consist of sequence of names and values separated by colons Compound keywords are used to generate multiple netlist lines for appl
262. lumns for tabulated data If not specified no limit will be set expression Expression to be displayed If expression is an array all values will be displayed Notes The display of arrays with a very large number of elements gt 500 can take a long time For large arrays it is recommended that the file switch is used to output the results to a file The file can then be examined with a text editor or spreadsheet program Unset UnSet temp option_name temp If specified the option setting will be deleted temporarily and will be restored to its original value when control returns to the command line i e when all scripts have completed Deletes specified option See Options on page 325 for a full explanation Note that some Option values are internal This means that they always have a value If such an option is UnSet it will be restored to its default value and not deleted See Options on page 325 for more details Function Summary 298 The following table lists a small selection of the functions available with SIMetrix Full documentation for these is provided in the Script Reference Manual This is available as a PDF file on the install CD Function name Description Page no abs real complex Absolute value 301 arg real complex phase result wraps at 180 180 301 degrees arg_rad real complex phase radians Result wraps at 301 pi pi radians atan real complex Arc tangent 301 cos real c
263. ly considering its implementation detail Your system may consist of a number of interconnected blocks each with an easily defined function 2 Device model implementation Functional models can be used to actually create device models Suppose you wish to use an op amp for which no model is available The only characteristic that affects the performance of your circuit is its gain bandwidth product So instead of creating a detailed model you simply use a differential voltage amplifier with the appropriate GBW SIMetrix provides functional modelling at both the schematic and simulator levels The schematic provides a convenient user interface to the functional devices provided by the simulator The simulator provides three devices that can be defined in a completely arbitrary manner These are defined in the following table See the Simulator Reference Manual for full details on these devices Chapter 5 Components Device Description Arbitrary non linear source Analog non linear device Can express single or B device voltage or current in terms of any number of circuit voltages and currents including its own output S domain Transfer Function Linear block with single input and output each Block of which may be single ended or differential voltage or current Specified in terms of its S domain or Laplace transfer function Arbitrary Logic Block Digital device Implements any digital device combinational synchronous or a
264. m point X1 is the x value of the first point on the curve that crosses Y max db_down starting at X max and scanning left to right Note that data is assumed to be raw simulation data and may be complex It must not be in dBs Implemented by built in script uf_Ipbw See install CD for source Overshoot Overshoot data xStart xEnd Finds overshoot in percent Returns yMax yStart yStart yEnd Chapter 9 Graphs Probes and Data Analysis Where yMax is the largest value found in the interval between xStart and xEnd yStart is the y value at xStart yEnd is the y value at xEnd If xStart is omitted it defaults to the x value of the first data point If xEnd is omitted it defaults to the x value of the last data point Implemented by built in script uf_overshoot See install CD for source PeakToPeak PeakToPeak data xStart xEnd Returns the difference between the maximum and minimum values found in the data within the interval xStart to xEnd If xStart is omitted it defaults to the x value of the first data point If xEnd is omitted it defaults to the x value of the last data point Implemented by built in script uf_peak_to peak See install CD for source Period Period data threshold Returns the period of the data Refer to diagram for the Duty function on page 271 The Period function returns X3 X1 Default value for threshold is Ymax Ymin 2 Where Ymax largest value in data and Y
265. mbinations of the following DefButton NMOS4 inst ne your_nmos4_symbol DefButton PMOS4 inst ne your_pmos4_symbol DefButton NMOS3IC inst ne your_nmos3_ symbol DefButton PMOS3 IC inst ne your_pmos3_ symbol Replace your_nmos4_ symbol your_pmos4 symbol etc with the internal names of your new symbols Automatic Area and Perimeter Calculation In the Micron versions of SIMetrix you can edit device length width and scale factor using the popup menu Edit MOS Length Width or by pressing alt F7 These menus alter the symbol properties W L and M for width length and multiplier The symbols described above have been designed in a manner such that additional parameters such as AS AD PS PD NRS and NRD may be automatically calculated from width and length To use this facility append the VALUE property with the parameter definitions defined as expressions E g N1 AD 2 SW S 0 8u The above device will have an AD parameter calculated from 2 width 0 8u Note that the formula is enclosed in curly braces and width and length expressed as W and L respectively You can use similar expressions for any other parameter As an alternative you can define AS AD etc as a parameter expression in a sub circuit See Subcircuits on page 149 for more details Chapter 4 Schematic Editor Editing the MOS Symbols You may wish to create your own MOS symbols for each process you use We suggest that yo
266. min in smallest value in data Implemented by built in script uf_period See install CD for source PulseWidth PulseWidth data threshold Returns the pulse width of the first pulse in the data Refer to diagram for the Duty function on page 271 The PulseWidth function returns X2 X1 Default value for threshold is 275 User s Manual 276 Ymax Ymin 2 Where Ymax largest value in data and Ymin in smallest value in data Implemented by built in script uf_pulse_width See install CD for source Rise Rise data xStart xEnd Amplitude Vy Function returns the 10 to 90 rise time of the first rising edge that occurs between xl and x2 The 10 point is at y threshold Y1 Y2 Y1 0 1 and the 90 point is at y threshold Y1 Y2 Y1 0 9 If xStart is specified X1 xStart otherwise X1 x value of first point in data If xEnd is specified X2 xEnd otherwise X2 x value of last point in data If xStart is specified Y1 y value at xStart otherwise Y1 maximum y value in data If xEnd is specified Y2 y value at xEnd otherwise Y2 minimum y value in data XatNthY XatNthY data y Value n Returns the x value of the data where it crosses yValue for the nth time XatNthYn XatNthYn data yValue n Returns the x value of the data where it crosses yValue for the nth time with a negative slope XatNthYp XatNthYp data yValue n Returns the x value of the data where it crosses yValue
267. mnt cdrom linux simetrix tar 4 You can skip this stage if you are using Redhat 8 or later or SusE 8 1 or later Extract the lib_extra tar file tar xf mnt cdrom linux lib_extra tar 5 This stage is optional A number of example files are also provided and these may also be installed if required Simply copy the examples tree to a suitable location where you have read write access We recommend HOME simetrix examples mkdir home username simetrix cp R mnt cdrom examples home username simetrix You will also need to change the ownership of the examples chown R username group home username simetrix Replace username and group as appropriate The examples will still run if you leave the ownership at root but you will not be able to edit the schematics 6 To start Simetrix run usr local simetrix_53 bin SIMetrix You may wish to set up some appropriate means to start simetrix in a more convenient manner such as by creating an icon for your chosen desktop environment 7 Ifyou have purchased a stand alone license you should leave the CDROM mounted for the time being as your license file will usually be located on it 8 Exit to user mode Installing to Other Locations The above procedure will install SIMetrix to usr local simetrix_53 and additional files to usr lib simetrix v5 3 You may relocate the entire usr local simetrix_53 tree to any location that you choose but you must keep the complete structure intact 17
268. models in the library when a simulation is run This has the following benefits s It makes the schematic completely self contained This is useful for archiving or if you wish to pass the schematic to a third party You can edit the models locally without affecting the global library To import models to a schematic select the schematic menu Simulator Import Models You will be provided with two options Import Direct Copy and Import by Reference The first will import the model text directly into the schematic The second will put the model text into a file This will be referenced in the schematic s simulator command window using a INC control See Command Reference chapter of the Simulator Reference Manual Sundry Topics LIB Control The LIB netlist control allows the local specification of model library for a particular circuit Syntax LIB pathname pathname File system path name specifying a single file or by using a wildcard or a group of files If the path name contains spaces it must be enclosed in quotation marks 165 User s Manual 166 This control specifies a pathname to be searched for model and subcircuit libraries Any number of LIB controls may be specified and wild cards i e and may be used Ifa model or subcircuit is called up by a device line but that definition was not present in the netlist SIMetrix will search for it in files specified using the LIB control SIM
269. more appropriate method See Hierarchical Schematic Entry on page 80 for details This section explains how to create a subcircuit from a schematic and how to reference one in netlist or schematic For the SUBCKT control syntax see the Command Reference chapter of the Simulator Reference Manual Creating a Sub circuit from a Schematic Subcircuits must be defined in text form as a netlist However the schematic editor can be used to generate the netlist To create a sub circuit from a schematic you need to identify which nodes are to be connected externally This is done using the same Module Port symbol used for hierarchical schematic entry see Hierarchical Schematic Entry on page 80 The procedure for defining a subcircuit is as follows 1 Draw circuit using schematic editor including module port symbols to identify external connections 2 Create netlist for circuit To describe the procedure we will use an example 149 User s Manual Stage 1 Draw Schematic This is circuit of a simple op amp In fact it is the circuit of our fictitious SXOA1000 op amp used in Tutorial 3 See page 49 a Q5 Pi Qi Nt SZ p1 i 0 our T Ri iN cl D 1K SZ o INP can ik a3 aa a2 INN 2 n 100u 100u Ds D r VSN The five terminal symbols e g VSN a a lt D v are the connections to the outsid
270. must enter the total number of points Device Parameter Model Name The device name for a device sweep parameter name for a parameter sweep or the model name for a model parameter sweep may be entered here It may also be entered in the sweep mode dialog opened by pressing Define Define Sets up desired sweep mode See Setting up a Swept Analysis on page 179 Monte Carlo and Multi step Analysis See page 194 See Also DC in Simulator Reference Manual Example The following is the result of a DC sweep of V3 in the example circuit shown on page 178 with restail set to 1K Analysis parameters were as follows Sweep mode Device V3 Sweep range 0 1 to 0 1 linear sweep with 50 points Output mV DC transfer function of simple diff amp 100 80 60 40 20 0 20 40 60 80 100 V3 mV 20mV div 181 User s Manual AC Sweep 182 An AC analysis calculates the small signal response of a circuit to any number of user defined inputs The small signal response is computed by treating the circuit as linear about its DC operating point Like DC AC Noise and Transfer Function analyses AC analysis is a swept mode and can operate in any of the 6 modes documented in Sweep Modes on page 176 With some of these modes e g sweeping a resistor value it will be necessary for the DC operating point to be recalculated at each point while with others such as
271. mutual 136 non linear 133 146 sweeping 177 InhibitAutoCD option variable 336 Initial condition capacitor 138 force resistance 193 inductor 138 inode template property keyword 109 Installation 15 integ function 305 Integration method 172 Interp function 305 InvertCursors option variable 336 IsComplex function 306 J join template property keyword 113 join_num template property keyword 113 join_pin template property keyword 113 K Keyboard 285 L Laplace expression 146 length function 306 LibraryDiagnostics option variable 336 Licensing 18 network 19 stand alone 18 List file 261 In function 306 358 Index log function 306 log10 function 306 LogicDefExtension option variable 345 lot property 105 LPBW function 274 M mag function 307 mappednode template property keyword 108 mappedpinnames template property keyword 108 mapping property 105 match property 105 maxidx function 307 Maxima function 307 MaxVectorBufferSize option variable 337 MC_ABSOLUTE RECT option variable 317 MC_MATCH_ RECT option variable 317 Mean calculating 248 function 308 Mean function 308 Menu reference 285 Menu short cuts 350 Message window 285 MinGridHeight option variable 337 minidx function 308 Minima function 308 Minimum function 309 MinorGridPrintWidth option variable 337 Mirroring schematic components 54 71 Model libraries LIB 165 associating models with symbols 161 diagnostics 166 duplicates 166 importing
272. n Resistance else if control voltage lt Off Voltage Resistance Off Resistance If Off Voltage gt On Voltage If control voltage gt Off Voltage Resistance Off Resistance else if control voltage lt On Voltage Resistance On Resistance If the control voltage lies between the On Voltage and Off Voltage the resistance will be somewhere between the on and off resistances using a law that assures a smooth transition between the on and off states Chapter 5 Components Switch with Hysteresis An alternative switch device is available which abruptly switches between states rather than following a continuous V I characteristic This device can be used with both SIMetrix and SIMPLIS although the behaviour is slightly different in each The switching thresholds are governed by an hysteresis law and when used with the SIMetrix simulator the state change is controlled to occur over a fixed time period currently 10nS This device can be placed on a schematic with the menu Place Analog Functions Switch with Hysteresis Generic ADCs and DACs Generic data conversion devices are available from the menus Place Digital Generic ADC and Place Digital Generic DAC t Define A D Converter E Define D A Converter Number of bits 8 Timings Number of bits 8 3 Convert time du Timings Max conversion rate 2Meg Output slew time 100n Input Offset volts 0 Output Offset volts 0 Range volts 5 Range volts 5
273. n be installed by dropping their files in the command shell with no other action being required Only subcircuit devices may receive embedded association information The information is placed in a specially formatted comment line after the SSUBCKT line but before the first device or command The line is in the form ASSOC Category category Symbol symbol Mapping mapping category Category for part If it has spaces this must be enclosed in double quotation marks symbol Internal symbol name to be used for part mapping Mapping information This changes the mapping between the subcircuit terminals and the symbol pin order Usually its easiest simply to arrange the subcircuit pin order to match the symbol pin order in which case this is not required If however there is some reason why rearranging the subcircuit pins is not desirable you can instead specify the pin order using the mapping value The mapping value is a list of symbol pin numbers that match to the corresponding subcircuit terminal So a mapping value of 2 3 1 says that the first subcircuit terminal connects to pin 2 of the symbol the second subcircuit terminal connects to pin 3 and the third to pin 1 Example SUBCKT IRF530 DGS ASSOC Category NMOS Symbol nmos_sub 163 User s Manual 164 ENDS Priorities Its possible that association information could be provided from multiple sources in which case the possibility of conflict arises If this is the
274. n place the command to define it in the startup file To do this select command shell menu File Scripts Edit Startup and add the line above Examples To define control R to place a resistor on the schematic sheet enter the command DefKey CR inst res 4 The built in definition for F12 to zoom out a schematic is DefKey F12 SCHEM zoom out 4 This definition only functions when a schematic is active A similar definition for F12 GRAPH zooms out a graph when a graph window is active See Also User Defined Key and Menu Definitions on page 350 DefMenu DefMenu immediate shortcut key_code menuname command_string when_to_enable Defines custom menu immediate Immediate mode Command is executed immediately even if another operation such as a simulation run or schematic editing operation is currently in progress For other options the command is not executed until the current operation is completed Only a few commands can be assigned with this shortcut key_code menuname when_to_enable Chapter 11 Command and Function Reference option See DefMenu command documentation in the Script Reference Manual for full details Specify key or key combination to activate menu Key description is placed on right hand side of menu item Use any of the codes specified in DefKey on page 290 except key pad codes Note that DefKey has precedence in the event of the key or key combination being defined by both DefKey and
275. n transistors Q 1 c Collector 2 b Base 3 e Emitter 4 s Substrate Capacitor Cc 1 p 2 n Chapter 4 Schematic Editor Device Model Pin no Pin Pin function property names Current Controlled Current F 1 p Source 2 terminal 2 n Current Controlled Current F 1 p output Source 4 terminal 2 n output 3 any control 4 any control Current Controlled Voltage H 1 p Source 2 terminal 2 n Current Controlled Voltage H 1 p output Source 4 terminal 2 n output 3 any control 4 any control Current Source l 1 p 2 n Diode D 1 p Anode 2 n Cathode GaAs FETs Z 1 d Drain 2 g Gate 3 s Source Inductor L 1 p 2 n Junction FET J 1 d Drain 2 g Gate 3 s Source MOSFET M 1 d Drain 2 g Gate 3 s Source 4 b Bulk Resistors R 1 p Transmission Line T 1 p1 Port 1 Term 1 lossless 2 n1 Port 1 Term 2 O lossy 3 p2 Port 2 Term 1 4 n2 Port 2 Term 2 Voltage Controlled Current G 1 p output Source 2 n output 3 cp contol 4 cn control 123 User s Manual 124 Device Model Pin no Pin Pin function property names Voltage Controlled Switch S 1 p Switch term 1 2 n Switch term 2 3 cp control 4 cn control Voltage Controlled Voltage E 1 p output Source 2 n output 3 cp control 4 cn control Voltage Source V 1 p output 2 n output Subcircuits X Pins can be given any name Numbering must be in the order that pins appear in the subckt control which defines the subcircuit SIMetrix uses a special e
276. n zero the function will return the value of argument 2 Otherwise it will return the value of argument 3 Note that the type of arguments 2 and 3 must both be the same No implicit type conversion will be performed on these arguments IIR real real real Vector to be filtered Coefficients Initial conditions default zero Performs Infinite Impulse Response digital filtering on supplied vector This function performs the operation Yn Xn Co Yn 1 C1 Yn 2 C2 Where x is the input vector argument 1 c is the coefficient vector argument 2 y is the result returned value The third argument provide the history of y i e yY y etc as required The operation of this function and also the FIR function is simple but its application can be the subject of several volumes In principle an almost unlimited range of IR filtering operations may be performed using this function Any text on Digital Signal Processing will provide further details Users should note that using this function applied to raw transient analysis data will not produce meaningful results as the values are unevenly spaced If you apply this function to simulation data you must either specify that the simulator outputs at fixed intervals select the Output at interval option in the Choose Analysis dialog box or you must interpolate the results using the Interp function see page 305 Example The following graph shows the result of a
277. name without extension of working catalog file OUT CAT The following options set default file extensions See options dialog for more details Chapter 13 Sundry Topics Option name Default Description value CatalogExtension cat Catalog files ComponentExtension sxcmp Schematic component files DataExtension sxdat dat Data files GraphExtension sxgph Graph binary files LogicDefExtension Idf Arbitrary block logic definition files ModelExtension Ib lib mod cir SPICE model files SchematicExtension sxsch sch Schematic files ScriptExtension sxscr txt Scripts SnapshotExtension sxsnp Simulator snapshot files SymbolExtension lib Binary symbol files TextExtension txt net cir mod Text files Idf sxscr lib lb cat Toolbar Buttons The buttons displayed on each of the standard toolbars are defined with an option variable that is one for each toolbar The value of the option consists of a series of semi colon delimited button names A complete list of button names and full information concerning user defined toolbars can be found in the Script Reference Manual The toolbar option variable names are listed below Option name Description ComponentButtons Schematic parts in SIMetrix mode CommandShellMainButtons Command shell toolbar SIMPLISComponentButtons Schematic parts in SIMPLIS mode SchematicMainButtons Schematic main toolbar SchematicFileButtons Schematic file operations toolbar SymbolMainButtons Symbol editor toolbar
278. naming of models but no renaming will actually take place Old Duplicate Name System Older versions of SIMetrix 4 1 and earlier were able to handle duplicate model names directly This system is no longer supported 167 User s Manual Chapter 7 Analysis Modes Overview In this chapter we describe the various analysis modes available and how to set them up from the schematic editor There is more information on analysis modes including full details of the netlist commands to invoke them in the Command Reference chapter of the Simulator Reference Manual Most of the analyses can be setup using the Choose Analysis Dialog Box which is opened with the schematic menu Simulator Choose Analysis E Choose Analysis x Transient AC DC Noise TF Options SOA CO Transient Transient parameters 0 AC Stop time Im aj DC Sweep C Noise Data output option a sae CO Transfer function Start data output p z Default c peor PRINT step 20u s Default Output all data Output at PRINT step Real time noise J Enable realtime noise Define Monte Carlo and multi step analysis C Enable multi step Define Selected mode None Cancel Define Snapshots Advanced Options Help dag i x Choose Analysis Dialog You can also enter the raw netlist commands in the F11 window The contents of this window remain synchronised with the Choose Analysis dialog box setting
279. nces of symbols with one and only one pin Returns the value of prop_name on an instance attached directly to the single pin of the device For example in the following R1 P 1K R1 lt JOIN REF gt on the probe R1 P would return R1 as this is the value of the REF property of the resistor In situations where more than one instance is connected to the pin index may be used to specify which one index may have a value between 0 and 1 less than the number of devices connected Use lt join_num gt to determine how many devices are connected Note that the pin of the device must be directly connected i e with pins superimposed and not by wires lt JOIN gt is intended to be used for current probes JOIN_NUM lt JOIN_NUM gt Only valid for single pin instances Returns number of joined devices See lt JOIN gt above for details JOIN_PIN lt JOIN_PIN index gt 113 User s Manual Only valid for single pin instances Returns connected pin name for another device connected to this device s only pin This can be used in conjunction with lt JOIN gt to return the current vector for a component E g lt JOIN REF gt lt JOIN PIN gt for the probe device in would return R1 p In situations where more than one instance is connected to the pin index may be used to specify which one index may have a value between 0 and 1 less than the number of devices connected Use lt join_num gt to determine how many devices are c
280. ne 4 Select OK 5 Proceed with entering symbol specification see below To Create a New Symbol From an Existing One 1 Select symbol to use as base from description box Note that only symbols originally created with the symbol generator and not subsequently edited with the graphical editor will be listed 2 Select Copy Button 3 Proceed as for creating new described above Symbol Shape Select Rectangle or Triangle A triangle shape converges to a point on the right Triangle symbols may only have one pin defined on the right 89 User s Manual Pins Select Pin Definition tab 1 Enter pin name This can be anything but may not have spaces Also avoid pin names with arithmetic characters such and This isn t an error but will introduce restrictions if plotting currents into a pin of the symbol on a schematic 2 Select where you want the pin to be put on the symbol with the Left Right Top and Bottom radio buttons 3 Ifyou want the name of the pin to be shown on the symbol ensure the Name Visible check box is checked 4 Press Add The pin description will appear in the list box 5 Repeat for all pins Netlist Order Each time you enter a new pin the Netlist Order box will increment Each pin must have a unique netlist order value and the values must be contiguous If you are creating a symbol to be used as a hierarchical block the netlist order is unimportant SIMetrix uses the pin name to match blo
281. ne and also to identify the seed value used for that Monte Carlo step Cursor Functions There are four functions which return the current positions of the cursors and these can be used in script expressions These are XDatum YDatum XCursor YCursor See Script Reference Manual for details This is available as a PDF file on the install CD A hardcopy version is also available for an additional charge Curve Measurements Overview A number of measurements can be applied to selected curves The results of these measurements are displayed below the curve legend and are also printed Some of these measurements can be selected from the tool bar and more can be called directly from the Legend Panel s pop up menu Right click in Legend Panel see Elements of the Graph Window on page 212 The remainder are listed in a tree structured list that is opened with the legend panel menu More Functions or by pressing F3 Note that the legend panel may be resized by dragging its bottom edge with the mouse In general to perform a measurement select the curve or curves then select measurement from tool bar or legend panel popup menu If there is only one curve displayed it is not necessary to select it Available Measurements The following table list all the measurements available and how they may be accessed 247 User s Manual 248 Transient measurements RMS Full RMS Per Cycle RMS Cursor span RMS AC
282. ning transient analysis settings see Transient Analysis on page 170 63 User s Manual 64 Periodic Operating Point Analysis POP AC Transient Triggering o Use POP Trigger schematic device See menu Place gt Analog Functions gt POP Trigger Trigger gate Trigger conditions Oto 1 ito0 Conditions Max period lu j Cycles before a launching POP ra To setup a POP analysis 1 Select Periodic Operating Point sheet 2 Check the POP box under Select analysis 3 Check the Use POP Trigger Schematic Device box You will need to place a POP trigger device on your schematic See below 4 In the Max period box enter a value that is larger than the largest possible value of your circuits switching period You must place on your schematic a POP trigger device Select menu Place Analog Functions POP Trigger After placing the device connect its input to a switching frequency signal You do not need to connect the output of this device Select the trigger device then press F7 Enter suitable values for Ref Voltage and Hysteresis so that it will always reliably trigger on the switching waveform If you don t use the output there is no need to change the other parameters AC Analysis Transient AC DC Noise TF Options Sweep parameters Start frequency 1k Decade Stop frequency 1Meg O Linear Points per decade 25 4 Mode Frequency To setup an AC analysis Ch
283. nstall system model libraries ifempty install libraries if there are no libraries currently installed merge merge system libraries with currently installed libraries no do not install system libraries Install system symbol libraries ifempty install libraries if there are no libraries currently installed merge merge system libraries with currently installed libraries no do not install system libraries The settings in the above table should be placed in the file in Options section in the form 347 User s Manual Options name value For example Options BuildSymbolLibs merge Skeleton Configuration File The skeleton configuration file if it exists will be copied to base sxprj if base sxprj does not exist The skeleton configuration file must be called skeleton sxprj and be located in the same directory as the executable file SIMetrix exe windows or SIMetrix Linux Installation Customising It isn t possible to customise the Windows install program However the SIMetrix installer doesn t do much more than simply uncompress files to the chosen location It is therefore possible for you to create your own SIMetrix install process using a fresh install tree as a source image You can then add your own files to this including the skeleton sxprj file described above Colours and Fonts 348 Colours Colours for schematic symbols wires graph curves and graph grids may be customised u
284. nt on a symbol at the definition stage but its initial value is not important as it would usually be changed after the symbol is placed on a schematic This property usually has a value that is a single letter that specifies the type of device For sub circuits and hierarchical blocks this letter must be X For other types of device refer to the table in Summary of Simulator Devices on page 122 If this property is not present the first letter of the ref property will be used to identify the device For information only The value of this property and a symbol are prefixed to the ref property to obtain the first word of the device line in the netlist hence complying with SPICE syntax This won t be done if the first letter of the Ref property is already the same as the value of the model property as this would be unnecessary This is only required for the SlMetrix SIMPLIS product It declares which simulator the symbol is compatible with This is only for the purpose of advising the user if a component may not work with a particular simulator It does not affect the functionality of that component for any simulator This property can have one of three values SIMetrix Symbol compatible with SiMetrix simulator only SIMPLIS Symbol compatible with the SIMPLIS simulator only Dual Symbol compatible with both SIMetrix and SIMPLIS Chapter 4 Schematic Editor Placing Symbol on Schematic After symbol definition is comp
285. nt run They can also be created on demand at any point during a transient run by first pausing the run and then manually executing the save snapshot command So for example if you find your amplifier reaches an unstable point during a transient analysis you can stop the analysis save a snapshot and then subsequently analyse the small signal conditions with an AC sweep An option is also available to save the DC operating point data to the list file at the point at which snapshots are saved Defining Snapshots Before a Run Starts 1 Select menu Simulator Choose Analysis 2 Inthe Transient Sheet select button Define Snapshots 3 You will see the following dialog 173 User s Manual 174 Define Snapshots Snapshot locations Snapshot mode Start time 100u Write bias info Linear sequence to list file S amp top time 1m Save state for a iN amp interval 100u Ac TFD Noise analysis O List Write bias info None O E and save state efine Lis Select either Linear sequence or List to define the time points at which the snapshots are saved In the Snapshot mode box select one of the three options Write bias info to list file Instructs the simulator to write the DC operating point data to the list file Does not save snapshot data Save state for AC TF Noise analysis Instructs the simulator to save snapshot data only No bias point information will be output to the list file
286. nte Carlo analysis in SIMetrix has been designed to be quick to set up for simple cases while still providing the required flexibility for more advanced requirements as might be required for integrated circuit design In this chapter we cover the aspects of setting up a Monte Carlo analysis from the front end This includes setting device tolerances in the schematic setting up and running a Monte Carlo simulation and analysing the results This chapter covers Monte Carlo analysis for S Metrix SPICE simulations Monte Carlo analysis is also available for SIMPLIS simulations See Multi step and Monte Carlo Analyses on page 206 Setting model tolerances is not covered here but in the Monte Carlo Analysis chapter in the Simulator Reference Manual Consider the following active filter circuit 6 2n 8 2n 10 10 C vour it ct ca 33k 33k 33k 33k 33k x1 1 1 1 1 1 rl oe an amp co P R7 R1 R2 R3 R6 v1 ac 1 eles _L 10 Thora LIV C2 2 7n L 10 cs 62p This circuit can be found in EXAMPLES MonteCarlo cheb sxsch The circuit is a 5th order low pass 7kHz Chebyshev filter with a 1dB passband ripple specification Its nominal response is 313 User s Manual 314 X1 out V 1k 2k 4k 10k 20k 40k 100k Frequency Hertz This circuit is to be used in an application that requires the gain of the am
287. nu Place Worksheets The worksheet menus automatically protect the worksheet after it has been placed This prevents it from being selected To delete a worksheet use the Place Worksheet Delete Worksheet menu You should avoid placing a worksheet from the Place From Symbol Library menu as it will not be protected if you do this 79 User s Manual Finding and Specifying Net Names When a simulation is run a netlist of the schematic is created and this is delivered to the simulator The netlist generator automatically assigns names to every net or node of the circuit There are some situations where you need to find the name of a net For example in noise analysis see page 183 you must specify an output node In these situations you can either find the name of the net that the netlist generator assigned or alternatively you can specify a name of your choice To Find an Assigned Net Name Place the mouse cursor on the net of interest You will see the name appear in the fifth entry of the status box at the base of the schematic window in the form NET netname Note that the schematic must have been netlisted for this to work Netlisting occurs when you run a simulation for example but you can force this at anytime by selecting the menu Simulator Check To Specify a User Defined Name User defined net names can be specified using either the Terminal symbol or the Small Terminal symbol Select menu Place Connectors Terminal or Pl
288. o Analysis 2 Select Options tab and enter the seed value in the Monte Carlo section The first run of each Monte Carlo analysis will use the same random values as the run from which you obtained the seed value in the log file Note this assumes that only changes in values are made to the circuit Any topology change will upset the sequence This technique is a convenient way of investigating a particular run that perhaps produced unexpected results Obtain the seed used for that run then repeat with the seed value but doing just a single run You will then be able to probe around the circuit and plot the results for just that run Analysing Monte Carlo Results Plots Plots of Monte Carlo analyses are performed in exactly the same manner as for normal runs When you probe a circuit point curves for each run in the MC analysis will be created You will notice however that only one label for each set of curves will be displayed Operations on curves such as deleting and moving will be performed on the complete set Identifying Curves Sometimes it is useful to know exactly which run a particular curve is associated with To do this proceed as follows 1 Switch on graph cursors Cursors Toggle On Off menu 2 Pick up the main cursor the one with the short dashes and place it on the curve of interest To pick up a cursor place mouse cursor at intersection press left key and drag 3 Select Show Curve Info menu Information ab
289. o do this rotate the marker before placing by pressing the rotate toolbar button or the F5 key To place a current marker use the menu Place Bias Annotation Place Current Marker To place markers as all nodes select Bias Annotation Auto Place Markers This does however clutter up the schematic and you may prefer to place them manually Chapter 9 Graphs Probes and Data Analysis To display the values select Bias Annotation Update Values These values are automatically updated after each simulation run The menu Bias Annotation Delete Markers deletes all the markers and Bias Annotation Hide Values removes the text but leaves the markers in place Displaying Device Operating Point Info The menu Bias Annotation Display Device Bias Info will display in the message window the node voltages pin currents and total power dissipation for the selected schematic component Note that power dissipation is calculated from the node voltages and currents List File Data A great deal of information about each device in the circuit can be obtained from the list file Use command shell menu Graphs and Data View List File or Graphs and Data Edit List File to see it Also see the Simulator Reference Manual for more information about the list file Other Methods of Obtaining Bias Data You can also display a voltage or current in the command shell without placing any component on the schematic For voltages place the mouse cursor over the point of inte
290. o set up a DC Sweep select the DC Sweep check box at the right and the DC tab at the top You will need to enter some values in the Sweep Parameters section 59 User s Manual 60 Transient AC DC Noise TF Options Sweep parameters Start value 0 s O Decade Stop value 5 s a Linear Number of points 50 Device name Mode Device The analysis will sweep the device you specify in the Device name box over the range specified by Start value Stop value and Number of points or Points per decade if you select a decade sweep The entry in the Device name box is the component reference of the device to be swept and for DC sweep would usually be a voltage source a current source or a resistor Device sweep is just 1 of 5 modes available with DC sweep The Define button allows you to specify one of the others See DC Sweep on page 180 for details AC Frequency Sweep An AC Frequency Sweep calculates the small signal response of a circuit to any number of user defined inputs over a specified frequency range The small signal response is computed by treating the circuit as linear about its DC operating point There must be at least one input source for AC analysis for the results to be meaningful Connect a voltage or current source to the circuit select it then press F7 In the dialog box select the Enable AC check box On the circuit an AC input voltage source will look something like this AC 1 0 v1 To
291. oefficient vector argument 2 y is the result returned value The third argument provide the history of x i e X4 X etc as required The operation of this function and also the IIR function is simple but its application can be the subject of several volumes Below is the simple case of a four sample rolling average In principle an almost unlimited range of FIR filtering operations may be performed using this function Any text on Digital Signal Processing will provide further details Users should note that using this function applied to raw transient analysis data will not produce meaningful results as the values are unevenly spaced If you apply this function to simulation data you must either specify that the simulator outputs at fixed intervals select the Output at interval option in the Choose Analysis dialog box or you must interpolate the results using the Interp function see page 305 Chapter 11 Command and Function Reference Example Suppose a vector VOUT exist in the current group simulation results The following will plot VOUT with a 4 sample rolling average applied Plot FIR vout 0 25 0 25 0 25 0 25 Alternatively the following does the same Plot FIR vout 0 25 unitvec 4 Floor real Returns the argument truncated to the next lowest integer Examples Floor 3 45 Floor 7 89 Floor 3 45 4 3 7 GroupDelay real complex Returns the group delay of the argument Group delay is defined a
292. of the standard distribution Note that this file is not automatically installed On Windows the examples are automatically installed to simetrix_root examples simetrix_root is the SIMetrix install directory which is typically C Program Files SIMetrix53 When the program first starts a shortcut at created in My Documents S Metrix Examples that points to simetrix_root examples But see A Note for System Administrators on page 16 In the following tutorial discussions the examples directory is referred to as EXAMPLES Simulation for the Novice When measuring a real circuit you would probably connect up a power source bench power supply perhaps maybe also some signal source then switch it on and take measurements using probably an oscilloscope You can also make adjustments to the circuit and see the effects straight away For simulation you have a choice of analysis modes and not all of them have an exact real life equivalent The analysis mode that most closely resembles the method of bench testing a circuit described above is transient analysis This performs an analysis over a specified by you time period and saves all the results i e all the voltages and currents in the circuit to your hard disk The difference between real life testing and simulation is that the simulation is not running all the time If you want to see the effects of changing a component value you have to change it then re run the simula
293. of the filter This is the junction of R1 and C2 You should see R1_P appear in the expression box We must now modify this with a goal function that returns the centre frequency The function CentreFreq will do this This measures the centre frequency by calculating the half way point between the intersections at some specified value below the peak Typically you would use 3dB Modify the value in the expression box so that it reads CentreFreq R1_p 3 At this stage you can optionally modify the graph setting to enter your own axis labels etc Now close the box This is what you should see Chapter 9 Graphs Probes and Data Analysis Mean 764 529 Frequency counts 730 740 750 760 770 780 790 Frequency Hertz 10Hertz div Note that the mean and standard deviation are automatically calculated Histograms for Single Step Monte Carlo Sweeps An example of this type of run is shown on page 179 These runs produce only a single curve with each point in the curve the result of the Monte Carlo analysis With these runs you do not need to apply a goal function just enter the name of the signal you wish to analyse To illustrate this we will use the same example as shown on page 179 Open the example circuit Examples Sweep AC_Param_ Monte Run simulation Select menu Probe Plot Histogram Te RS ak Left click on pin of the differential amplifier E1 You should see R4_N appear in the box
294. oints Define Sets up desired sweep mode See Setting up a Swept Analysis on page 179 Transfer Function Parameters Voltage Current Specify whether the output is a node voltage or device current Output node Output source This is compulsory If voltage mode is selected it is the name of the circuit node to which the gain of all circuit sources will be calculated It is the node name as it appears in the netlist Usually the schematic s netlist generator chooses the node names but we recommend that when running a transfer function analysis that you assign a user defined name to your designated output node To find out how to do this see Finding and Specifying Net Names on page 80 If current mode is selected it is the name of a voltage source through which the output current is measured The simulation will calculate the gain for every circuit source to this current Reference node Optional and only available in voltage mode Output voltage is referred to this node This is assumed to be ground if it is omitted Source name Optional Input impedance to this source will be calculated if specified Monte Carlo and Multi step Analysis See page 194 See Also TF in Simulator Reference Manual Plotting Transfer Function Analysis Results See Plotting Transfer Function Analysis Results on page 221 Example Perform transfer function frequency sweep on the following circuit 189 User s Manual
295. ome files that the uninstall program may leave behind To uninstall SIMetrix 1 In the system control panel select Add Remove Programs 2 Select SIMetrix then press Add Remove As explained above their may be some files left over and you will find these in the following locations Application root directory Typically this is C Program Files SIMetrixxx where xx represents the version number E g 53 for 5 3 Application data directory See Application Data Directory on page 325 In a directory called SIMetrixTempData under the system defined temporary directory This is the directory pointed to by the TEMP or TMP environment variables Typically on Windows 2000 or XP this is C Documents and Settings username Local Settings Temp At the time of writing Windows Vista had not been released but Beta versions were using a quite different directory for Application Data and Temporary files Any other location specified in a Save operation SIMetrix will not place files in any other location unless you explicitly ask it to A Note for System Administrators The SIMetrix standard installation makes some assumptions about how the user s system is setup and used as follows 1 The user has exclusive access to the machine 2 The user has administrator privilege If these conditions don t apply then some minor modifications may need to be made The main issue is the examples directory This contains a number of examp
296. omplex Cosine 301 Chapter 11 Command and Function Reference Function name Description Page no db real complex dB x 20 log10 mag x 301 diff real Return derivative of argument 301 exp real complex Exponential 301 fft real string Fast Fourier Transform 302 FIR real real real Finite Impulse Response digital 302 filter Floor real Returns argument truncated to 303 next lowest integer GroupDelay real complex Returns group delay of argument 303 Histogram real real Returns histogram of argument 303 Iff real any any Returns a specified value 304 depending on the outcome of a test lIR real real real Infinite Impulse Response digital 304 filter im imag real complex Return imaginary part of 305 argument integ real Returns integral of argument 305 Interp real real real real Interpolates argument to 305 specified number of evenly spaced points IsComplex any Returns TRUE if argument is 306 complex length any Returns number of elements in 306 vector In real complex Natural logarithm 306 log log10 real complex Base 10 logarithm 306 mag magnitude real complex Magnitude same as abs 307 maxidx real complex Returns index of vector where 307 largest value is held Maxima real real string Returns locations of maxima of 307 specified vector mean real complex Returns statistical mean of all 308 values in vector Mean 1 real real real Returns mean of data in g
297. on The menu to be deleted is identified by its position The first item in the menu is at position zero menuname Composed of strings separated by pipe symbol First name must be one of the following SHELL Command shell menu SCHEM Schematic popup menu GRAPH Graph popup menu LEGEND Popup menu in graph legend panel See Elements of the Graph Window on page 212 SCHEMMAIN Schematic main menu SYMBOL Symbol editor popup menu SYMBOLMAINSymbol editor fixed menu The remaining strings identify the menu and item names See DefMenu page 292 for details on menu names OpenGroup OpenGroup text overwrite filename Reads in a data file text If specified data file is assumed to be in text format Otherwise the file is input as a SIMetrix binary data file as saved by the SaveGroup command See Data Import and Export on page 277 for details of text format overwrite Forces existing group of the same name to be overwritten If not specified the group being read in will be renamed if a group of the same name already exists filename Name of file to be input If not specified an open file dialog box will be opened allowing the user to choose from available files OpenGroup creates a new Group If text is not specified then the name of the group will be that with which it was stored provided the name does not conflict with an existing group If there is a conflict the name will be modified to be unique If text is
298. on linear equations as SPICE does By modelling devices in this way SIMPLIS can characterise a complete system as a cyclical sequence of linear circuit topologies This is an accurate representation of a typical switching power system where the semiconductor devices function as switches However a linear system can be solved very much more rapidly than the non linear systems that SPICE handles The end result is accurate but extremely fast simulations allowing the modelling of complex topologies that would not be viable with SPICE SIMPLIS has three analysis modes Transient Periodic Operating Point and AC Transient analysis is similar to the SPICE equivalent but is typically 10 50 times faster Periodic Operating Point is a unique analysis mode that finds the steady state operating waveforms of switching systems AC analysis finds the frequency response of a switching system without needing to use averaged models This is especially useful for what if studies on new circuit topologies or control schemes where the small signal averaged model has not yet been derived Because non linear devices are defined using a sequence of straight line segments models for such devices are quite different from SPICE models There are of course many SPICE models available and so in order to retain compatibility with these SIMetrix SIMPLIS has the ability to convert models for some types of device into SIMPLIS format This conversion is performed when the device
299. onnected T lt T prop_name gt Does the same as prop_name except that the properties value is evaluated as if it were a template itself With prop_name the literal value of the property is always used Note that recursive properties will simply be substituted with nothing E g lt T TEMPLATE gt will return empty if used in a template property called TEMPLATE Further Information To put a new line in the netlist entry you can use a Literal new lines are also accepted To put a literal lt gt or character in the text use two of them So lt lt will become tet Template Scripts It is also possible to write a script to compile the line generated by the netlist generator Such scripts are called Template Scripts With this approach you enjoy the full power of the scripting language and very complex devices can be created in this manner For full details of this approach please refer to the Script Reference Manual Symbol Library Manager 114 The symbol manager is a comprehensive system for managing symbols and the libraries that store them To open the symbol library manager select command shell menu File Symbol Editor Symbol Manager The dialog shown below will be displayed Chapter 4 Schematic Editor o a Symbol Library Manager Library Manager Symbols connection sxslb Al Symbols semiconductors sxslb Semiconductors amp BJTs NPN schottky default sxslb mis
300. oolbar v 0s cccenh cision sien 213 Probes Fixed vs Random cceeeeeeeceeeseeesesneeeeeeees 213 Fixed Probes ocenia e e eects eee eet 214 Fixed Voltage and Current Probe Options 215 Fixed Bus Probe Options ccccceeeeeseeeeeeeees 217 Using Fixed Probes in Hierarchical Designs 218 Adding Fixed Probes After a Run has Started 218 Changing Update Period and Start Delay 218 Random Probes iaieineea e na akane e aiana 218 General Behavioul ecceeeseeeserceeeeneeeeeneeeeneeeens 218 F NC ONS aie iae ae ae a aae a E dee 219 User s Manual 10 Notes on Probe Functions 220 Plotting Noise Analysis Results 0 cceee 221 Plotting Transfer Function Analysis Results 221 Fourier Analysis c005 c0s0ds ce orev 222 Probing BUSSES ss ccsctscsceteeccyes scesheigestateezites sd neiii 226 Bus Probe Options eeen 227 Plotting an Arbitrary Expression 228 Using Random Probes in Hierarchical Designs 233 Plot Journals and Updating Curves eee 234 OVGIVIGW viiei pectecece ie inni earita 234 Update C rv Sirni a e alaia 235 Plot Journals 225 Acceee ecsdecisedesedicaeiceeeusinenssartenees 235 Graph Layout Multiple Y Axis Graphs 235 AutoAxis Feature 237 Manually Creating Axes and Grids 237 Selecting AXES sison iyiot tais pinsdrig iid ianen 237 Moving Curves to Different Axis or Grid 237 Deleting AXES niaii
301. or all features then there is no problem If however you have fewer for example digital licenses than basic licenses then a problem could arise where the first users that check out licenses use up all the digital licenses leaving these features unavailable for later users This would be a waste if the earlier users were not actually using the features To overcome this SIMetrix has a command line switch that instructs it what licenses to check out The syntax is SIMetrix f basic micron digital advanced rtn Chapter 1 Introduction You can remove any of the feature names from the above other than basic to prevent those features from being checked out The above allows you to setup alternative short cuts or desktop icons to checkout different combinations of features The FLEXIm options file also allows you to reserve particular features for named users See the end user documentation for details Client Node Crashes If a user s client machine crashes while SIMetrix is running the license will not be immediately checked in but will be after a time out period of 5 minutes Before this time has elapsed the license can be checked in manually at the server by typing at the command line lmutil lmremove lt feature gt lt user_name gt lt host_name gt lt display gt For Windows display is the same as the host_name on Linux you will need to enter the display name which would usually be 0 0 feature will be one of basic digital
302. ot absolutely essential but it makes things much easier If they are not the same there is method of overcoming the problem using the mapping property This is explained in the section Properties on page 102 Creating symbols for the schematic is covered in Creating Schematic Symbols Overview on page 88 The symbol must have the following properties see page 102 Property Property value Purpose name Model X Ensures netlist line starts with X Identifies component as a subcircuit Should be hidden and protected Value subcircuit_name Name used to reference subcircuit definition Can be changed by user after placing on schematic Ref component_reference E g U Automatically allocated when placing symbol on schematic 151 User s Manual 152 Most symbols possess these properties anyway the important fact is that the model property must be set to X When defining a symbol from scratch these properties can be defined in one go in the graphical symbol editor with Property Pin Add Standard Properties To use the sub circuit definition SIMetrix must be able to find it There are various places where it can be put and means of telling SIMetrix of the location These are the choices 1 Place the definition directly in the simulator command or F11 window see Manual Entry of Simulator Commands on page 65 If placed at that location it will be read in unconditionally and SIMetrix will not need
303. ot executed until the current operation is completed Only a few commands can be assigned with this option See DefMenu documentation in the Script Reference Manual for full details Valid key labels Function keys F1 F2 F3 F4 F5 F6 F7 F8 F9 F10 F11 F12 INS DEL HOME END PGUP PGDN LEFT RIGHT UP DOWN TAB BACK ESC NUMI NUM2 NUM3 NUM4 NUMS5 NUM6 NUM7 NUM8 NUM9 NUMO NUM NUM NUM Insert key Delete key Home key End key Page up key Page down key lt _ gt t 4 Tab key Back space Escape key Keypad 1 Keypad 2 Keypad 3 Keypad 4 Keypad 5 Keypad 6 Keypad 7 Keypad 8 Keypad 9 Keypad 0 Keypad Keypad Keypad 291 User s Manual 292 NUM Keypad NUM Keypad _SPACE Space bar must always be shifted see below All letter and number keys i e A to Z and 0 to 9 referred to by letter number alone Shifted keys Any of the above prefixed with any combination of S for shift C for control or A for alt Note that in windows the right hand ALT key performs the same action as CONTROL ALT Notes Unshifted letter and number key definitions will not function when a text edit window such as the simulator command window F11 is active Space bar definitions must always be shifted The same codes can be used for menu short cuts See DefMenu command page 292 Key definition will be lost when SIMetrix is exited To make a key or menu definition permanent you ca
304. otted An alternative method of plotting single curves is given in Setting the Seed Value on page 318 Creating Histograms See Performance Analysis and Histograms on page 263 Chapter 13 Sundry Topics Chapter 13 Sundry Topics Symbolic Path Names Overview Some file system path names used by SIMetrix may be defined using a symbolic constant Such paths are of the form symbolYpath Where symbol is the name of the constant and path is any sequence of characters valid for a path name The actual path is resolved by substituting symbol with the value of symbol Symbolic paths make it easy to move files to new locations as only the values for their symbols need to be changed in order for SIMetrix to be able to continue to find them Definition There are two types of symbolic constant These are system constants and user constants system constants are pre defined while user constants can be arbitrarily defined by the user There are currently 5 system constants These are STARTPATH Full path of the current working directory from where SIMetrix was launched DOCSPATH Full path of the My Documents folder on Windows HOME on Linux EXEPATH Full path of the location of the SIMetrix binary SIMetrix exe on Windows SIMetrix on Linux APPDATAPATH Full path of the Application Data directory TEMPPATH Path of temporary directory User constants must be defined in the configuration file See Configuration Sett
305. ould like to migrate your old preference settings If you choose to do this your old settings such as colours fonts and window locations will be copied across but not any file locations including model libraries You will need to update these manually Also if you defined any new symbols they will not automatically be copied across See Symbol Library Manager on page 114 for details on how to copy symbols from an earlier version Please read Upgrade Notes on page 30 General Information All SIMetrix files are installed in the directory tree you specify to the setup program No files are copied to any other location and no system files are updated or added But SIMetrix does write files to other locations when it is run see Uninstalling below SIMetrix does not use any files that may be shared with other applications other than those that form part of the standard operating system This means that installing SIMetrix cannot affect the running of other applications SIMetrix does not use the system registry for any of its settings Some settings get written to the registry by the installer but SIMetrix itself does not use them Uninstalling SIMetrix in common with most applications includes an uninstall utility However the uninstall program does not remove everything from the system Any files that you 15 User s Manual 16 create will remain on your system The following describes where you may find s
306. out the curve will be displayed in the command shell This is an example of what will be displayed Source group acl Curve id 4 Run number 49 The information of interest here is the Run number With this you can look up in the log file details of the run i e what values were used for each component and parameter You can also obtain the seed value used so that the run can be repeated See Setting the Seed Value on page 318 Plotting a single Curve If you wish to plot a single curve in a Monte Carlo set you must obtain the run number then use the Probe Add Curve menu to plot an indexed expression We use an example to explain the process Using the Chebyshev filter example let s suppose that we wish to plot the curve of the filter output created by run 49 alone without the remaining curves Proceed as follows 319 User s Manual 320 a Run the chebyshev filter example as explained at the beginning of this chapter Select menu Probe Add Curve Click on the output of the filter You should see C4 _P entered in the Y expression box You must now modify the expression you have entered to give it an index value For the simple case of a single voltage or current just append it with index where index is the run number less 1 In this example the run number is 49 so we enter 48 for the index You should now have c4_P 48 displayed in the Y expression box Close box You should see a single curve pl
307. overshoot Maximum value of overshoot relative to pulse amplitude Absolute value of overshoot measured at pulse defined by cursor positions Value of overshoot relative to pulse amplitude measured at pulse defined by cursor positions Settling time to 1 Pulse defined by cursor positions Settling time to 0 1 Pulse defined by cursor positions Settling time to 0 01 Pulse defined by cursor positions Settling time to user defined specification Pulse defined by cursor positions Frequency measured over full span Frequency measured over span defined by cursor positions Distortion measured over full span Distortion measured over span defined by cursor positions 3dB point assuming a low pass roll off Chapter 9 Graphs Probes and Data Analysis Transient Access from Description measurements 3dB High pass Toolbar 3dB point assuming a menu More Functions _ high pass roll off 3dB Low pass menu More Functions 3dB point assuming a response with low frequency tit _ 3dB High pass menu More Functions 3dB point assuming a response with high frequency in__ Other Measurements Temperature coefficient menu More Functions Average temperature coefficient for temperature sweep only Total Noise menu More Functions Integrated noise for noise analysis only Repeating the Same Measurement The menu Measure Repeat Last Measurement will repea
308. ox Properties Label Background Colour DefaultLabel Edit Colour Font Items enclosed with are symbolic values See Edit Font help for details Label Lists each label in the box These are usually DefaultLabel which resolves to the name of the referenced curve To edit double click on the desired item You can also enter the symbols X1 and Y1 which represent the x and y co Chapter 9 Graphs Probes and Data Analysis ordinates of the marker respectively These can be combined with other text in any suitable manner For example Voltage X1 S Y1 might resolve to something like Voltage at 10u 2 345 The values of X1 and Y1 will automatically update if you move the marker You can also use expressions in the same manner as for cursor dimensions See Label on page 245 Background Colour Select button Edit Colour to change background colour To change the default colour select command shell menu File Options Colour then select item Text Box Edit colour as required Font Select button Edit Font to change font To change the default font select command shell menu File Options Font then select item Legend Box Edit font as required Text Box Placing Select menu Annotate Text Box Enter required text then Ok You can use the symbolic constants date Ytime and Yoversion to represent creation date creation time and the product version respecti
309. p Mode X Sweep mode Parameters Device Device name Parameter Parameter name restail Model parameter Temperature Frequency Monte Carlo Frequency Number of points 10 100k A gt Select the desired mode on the left then enter the necessary parameters on the right The parameters required vary according to the mode as follows Mode Parameters Device Device component reference e g V1 Frequency AC Noise and TF only Parameter Parameter name Model Parameter Temperature Frequency not available for DC Monte Carlo DC Sweep 180 Operates in any of the sweep modes described on page 176 except Frequency Repeats Frequency AC Noise and TF only Model name Model parameter name Frequency AC Noise and TF only Frequency AC Noise and TF only None Number of points Frequency AC Noise and TF only a DC operating point calculation for the range of circuit parameters defined by the sweep mode Setting up a DC sweep 1 Select menu Simulator Choose Analysis 2 Select DC sweep check box on the right 3 Select DC tab at the top Enter parameters as described in the following sections Chapter 7 Analysis Modes Sweep Parameters Start value Stop value Defines sweep range stop and start values Points per decade Number of points Defines sweep range The number of points of the sweep is defined per decade for a decade sweep For a linear sweep you
310. page 25 for details Installing Network Licensing for Windows Copying Files No automatic installation program is supplied but the process in nevertheless straightforward Simply copy all the files from the CD in the directory flexIm windows to a directory of your choice on the license server Also copy the license file that we supply you to the same directory License files have the extension clic Installing License Server as a Service We recommend that the license server is installed as a service When installed as a service the license manager will be running all the time even if no user is logged in and will automatically be started when the machine is booted To install as a service open a command prompt window i e a DOS prompt then CD to the directory where you copied the files Type at the command line installs This will install FLEXIm as a service and also automatically start it A log file will be created in the same directory called LMGRD LOG You will not need to repeat the above procedure when the machine is re booted The services will start automatically even if no user is logged on Monitoring Service You can check that the service has been installed using the Windows control panel The procedure is slightly different for Windows NT4 than Windows 2000 XP On Windows NT4 1 Open the Windows Control Panel 2 Select the Services icon 3 You should see FLEXIm License Manager as one of the services with th
311. pdateClosedSchematics option variable 233 342 pdateCurvesNoDeleteOld option variable 342 pdateCurvesNoFixSelected option variable 342 pgrade notes 30 seAltGraphPrintStyles option variable 342 seGreekMu option variable 342 seNativeXpSplitters option variable 343 SER CAT 164 serCatalog option variable 343 serScriptDir option variable 343 serSymbolsDir option variable 343 serSystemSymbolDir option variable 343 seSmallGraphCursor option variable 343 Ge ee c Ce eve GC eee Che Ee eevee lt value property 104 151 valuescript property 105 vector function 311 VertTextMode option variable 344 VNTOL 193 Voltage plotting 67 68 plotting differential 67 Voltage source controlled 140 fixed 139 sweeping 177 W WarnSubControls option variable 344 Window graph 212 schematic 70 symbol editor 93 WireWidth option variable 344 WorkingCatalog option variable 344 369 User s Manual Worksheets schematic 79 X XatNthY function 276 XatNthYn function 276 XatNthYp function 276 XatNthY pct function 277 XFromyY function 311 XY function 312 Y YatX 277 YatXpct 277 YFromX function 312 Z Zooming graph 253 370
312. pense of not being able to recover old data Curve weight Thickness of displayed curves Curves display much quicker if this value is set to 1 but are clearer but can lose detail if set to 2 Digital Axis Height Sets height of axes in mm used to plot digital traces Min grid height When a grid is added to a graph window existing grids are reduced in height to accommodate the new one But they won t be reduced to a height lower than specified by this setting When this limit is reached the vertical space will be increased by allowing the window to scroll Controls where cursor values are displayed On graph Values are displayed on the graph itself Status bar Values are displayed in status bar boxes at the bottom of the graph window Both Displayed in both locations as described above Controls the curve style used for histogram displays Stepped Displays a flat line for the width of each bin Similar to a bar Chapter 13 Sundry Topics graph Smooth Joins the centre of each bin with a straight line to display a continuous curve How data is stored For info only Simulation data is stored in temporary data files as explained above The data is not read into system memory until it is needed say to plot a graph However the location in the file of the various vectors is always in memory so that the data can be extracted from the file as rapidly as possible It is this latter location data that is destroyed wh
313. plained in detail below Keyword Description nodelist Substituted with full list of nodes for device pinlist Substituted with full list of pin names for symbol node n Substituted for individual node mappednode As node but order defined by mapping property if present pinnames Equivalent to pinnames lt pinlist gt except that no substitution takes place if the nopinnames switch is specified for the Netlist command mappedpinnames_ As pinnames but order is altered according to mapping property if present nodename This is not replaced by any text but signifies that the item following is a node name The netlist generator must be able to identify any text that is a node so that it can correctly substitute the name when required repeat Start of compound keyword to create a general purpose repeating sequence series Start of compound keyword to create a series combination parallel Start of compound keyword to create a parallel combination step Used by series and parallel to return sequence number if Conditional on the result of an expression ifd Conditional on whether a property is defined Chapter 4 Schematic Editor Keyword Description join join_pin Returns information about a connected device Used for join_num current probes sep Returns separator character Usually ref SPICE compatible component reference inode Generates an internal node t Substitutes a property value treating it as a
314. plication Data Windows XP Windows NT 4 C WINNT Profiles username Application Data Windows Unsupported platform 95 98 ME username is the log on name currently being used The above are only typical locations on English language versions of Windows The user or system administrator may move them and also the names used may be different for non English versions of Windows At the time of preparing this document Windows Vista had not been released However beta versions appeared to be using the directory C Users username AppData Roaming Specifying Other Locations for Config Settings You can specify alternative locations for the configuration settings This can be done with the c switch on the command line or ConfigLoc setting in the startup ini file See SIMetrix Command Line Parameters on page 323 for more details Options Overview There are a number of options affecting all aspects of SIMetrix Many of these may be viewed and adjusted using the Options dialog box others can only be accessed from the command line using the Set and UnSet commands 325 User s Manual Using the Options Dialog This is invoked with the menu File Options General This brings up the following A Options Preferences Schematic Graph Priniting Graph Probe Data Analysis Model Library Shell Scripts F p Undo level Double click mode Placement 1q Default O Classic Repeat for all symbols s Edit selected Repe
315. plifier to remain within 2dB of the dc value from 0 to 6kHz A 1dB ripple specification therefore seems a reasonable choice Clearly though the tolerance of the capacitors and resistors may upset this To investigate a Monte Carlo analysis is required The standard component tolerances are 10 for capacitors and 1 for resistors With the example circuit the tolerances are already applied but the procedure for doing this is as follows Select menu item Monte Carlo Set All Resistor Tolerances Enter 1 The is recognised Select menu item Monte Carlo Set All Capacitor Tolerances Enter 10 The example circuit has already been set up to run 100 steps of Monte Carlo To view the settings eS 1 Select menu Simulator Choose Analysis 2 Note in the section Monte Carlo and Multi step Analysis the Enable multi step box is checked 3 Press the Define button 4 Note that in the Sweep Mode section Monte Carlo is selected and in the Step Parameters section Number of steps has been set to 100 Start the analysis in the usual way It takes about 2 5 seconds with a 1 5G P4 The analysis will be repeated 10 times Now plot the output of the filter in the usual way Probe AC Noise dB Voltage The result is the following dbV X1 inn dB Chapter 12 Monte Carlo Analysis Frequency Hertz As can be seen the specification is not met for some runs The SIMetrix Monte Carlo analysis implementa
316. plot journal using the menu Plot Create Plot Journal then choose a file name The file created has a sxscr extension its the same extension used by scripts because the file created is a script To run the plot journal you will of course first need to run a simulation or load previous data so that the journal has some data to work with The plot journal itself does not store any data With the simulation data you wish to work with in place select either graph menu Plot Run Plot Journal or command shell menu Graph Run Plot Journal This simply runs a script located in the current directory Note that the plot journal always creates a new graph sheet Graph Layout Multiple Y Axis Graphs Graphs may have additional Y axes to accommodate plotting results with incompatible scales This occurs particularly for plotting dB and phase against each other and also for voltage and current The additional Y axes may either be superimposed or stacked In the user interface and the remainder of this documentation these are referred to respectively as Axes and Grids These are illustrated below 235 User s Manual PSU Waveforms Selected Joes Eile Edit Cursors Annotate Curves Axes View Measure Plot 9 QQ GDR HR REM FUSER m C 1L3 P v1 m C S2P 2 tran2 I L3 P Y1 Y2 y1 15 10 a z Ss o gt a amp a h s 0 5 TimekSecs 20Secsidiv x 2 07761kSecs y 16
317. polation order This can be any integer or greater but in practice there are seldom reasons to use values greater than 4 The Interp function overcomes some of the problems caused by the fact that raw transient analysis results are unevenly spaced It is used by the FFT plotting scripts to provide evenly spaced sample points for the FFT function The Interp function also makes it possible to perform operations on two vectors that originated from different transient runs and therefore will have different sample points 305 User s Manual 306 IsComplex any Returns 1 TRUE if the supplied argument is complex and 0 FALSE if the argument is any other type length any Returns the number of elements in the argument The result will be 1 for a scalar and 0 for an empty value The length function is the only function which will not return an error if supplied with an empty value Empty variables are returned by some functions when they cannot produce a return value All other functions and operators will yield an error if presented with an empty value and abort any script that called it In real complex Returns the natural logarithm of the argument Using In with Negative or Complex Values If the argument is real and 0 or negative an error will result If the argument is complex it will return a complex result even if the imaginary part is 0 and the real part negative E g in 1 will produce an error But
318. ponent will be displayed For devices requiring a model name a list of available types will appear To Rotate Mirror or Flip a Component Use the rotate toolbar button c or key F5 to rotate a component You can repeat pressing this button key until the desired orientation is reached It sequences through all 8 possible orientations This operation can be performed while a component is being placed or while a block is being moved or copied see below You can also select a component or block then press the rotate button key to rotate in situ 71 User s Manual 72 To mirror a component or block through the y axis press the mirror toolbar button or F6 key To flip a component or block mirror about x axis press Flip button or press shift F6 Wiring See Wiring on page 75 below Deleting Wires Select the wire by placing cursor over it clicking left button Press X button or press delete key Disconnecting Wires Press the shift key then select area enclosing the wire or wires to be deleted Press delete button To Move a Single Component Place the cursor within it and then drag it using the left mouse key You can rotate flip mirror the component see above while doing so To Move More Than One Item Select items as described above Place cursor within any of the selected items then drag the items to the desired location You can rotate flip mirror the items see above while doing so To Move Items
319. port number 27001 Specifying the Application Port Number When SIMetrix prompts you for server license information with C Get License Server Network License Details Please enter the name of the computer that is running the network license server press the Advanced button You will a dialog box like C Advanced Server Info Port Number 27001 Cancel O Use Default Value Port numbers defined here must match those in the license file See user manual for details enter the port number as required If you have already entered license information and wish to change it select the menu Help Reinstall License then restart SIMetrix This will force the re entry of license information Changing the Location of the License Server If you need to move the license server to a different machine then the end users machines will also need to be re configured To do this start SIMetrix then select the menu Help Reinstall License then re start This will delete all license information from the end user s machine When you re start SIMetrix you will be prompted to re enter the name of the license server Note that the above procedure can be used even if the license server is not running SIMetrix will still run with no license present but the simulator will be disabled License Server Version If you have upgraded SIMetrix from version 4 5 or earlier we strongly recommend that
320. pplying a simple first order IIR filter to a step Chapter 11 Command and Function Reference The coefficients used give a time constant of 10 the sample interval In the above the sample interval was 1luSec so giving a 10uSec time constant As can be seen a first order IIR filter has exactly the same response as an single pole RC network A general first order function is Yn Xn Co Yn 1 C1 where y 1 exp T t and c exp T t and t time constant and T sample interval The above example is simple but it is possible to construct much more complex filters using this function While it is also possible to place analog representations on the circuit being simulated use of the IIR function permits viewing of filtered waveforms after a simulation run has completed This is especially useful if the run took a long time to complete im real complex imag real complex Returns imaginary part of argument integ real Integrates the argument with respect to its reference x values The function uses simple trapezoidal integration An error will occur if the argument supplied has no reference Interp real real real real Vector to be interpolated Number of points in result Interpolation order Boolean include last point Returns a vector with length specified by argument 2 obtained by interpolating the vector supplied as argument at evenly spaced intervals The optional third argument specifies the inter
321. pt analysis page 176 or multi step analysis page 194 Expressions for device values must be entered enclosed in curly braces and Suppose we wish a 1kHz roll off for the above filter Using the PARAM control add these lines to the netlist using the F11 window see Manual Entry of Simulator Commands on page 65 PARAM fO 1k PARAM alpha 1 PARAM C1 10n Using the Let command you would type Let f0 1k Let alpha 1 Let C1 10n 155 User s Manual If you then wanted to alter the damping factor to 0 8 you only need to type in its new value Let alpha 0 8 then re run the simulator To execute the Let commands from within a script prefix the parameter names with global E g Let global f0 Lk In many cases the PARAM approach is more convenient as the values can be stored with the schematic Example passing parameters to subcircuits If the filter example above was implemented as a subcircuit different values of the parameters freq alpha and C1 could be passed to each instance of the subcircuit This allows several filters with differing roll off frequencies and damping factors to be quickly drawn 2 2 PI freq C1 alpha 2 2 PI freq C1 alpha RI R2 E OUT IN C1 alpha alpha 4 C2 You can set the values of the parameters for each instance of the above subcircuit by appending the expressions to the value property of the symbol in the main circuit separated
322. ptions below Bus Probe Options The following describes the options available for random and fixed bus probes These options are set using the dialog box shown below See Probing Busses above and Fixed Voltage and Current Probe Options on page 215 for details on plotting busses fa Define Bus Plot x Define Bus Label Bus1 default Start 0 A default End 5 Aj default Define Plot Define Analog Waveform Range 5 Offset 2 5 Units Volts Digital display Decimal Digital display Hex Digital display Binary Analog waveform Hold invalid states Define Bus Label This is how the curve will be labelled in the plot Start End Defines which wires in the bus are used to created the displayed data The default is to use all wires Plot Type Decimal Hexadecimal Binary Each of these specifies a numeric display see below showing 227 User s Manual 228 Analog waveform Hold invalid states the bus values in the number base selected Specifies that the bus data should be plotted as an analog waveform If checked then and invalid digital states found in the data will be replaced with the most recent valid state If not checked invalid states will be shown as an X in numeric displays This option is automatically selected for analog waveform mode Define Analog Waveform Only enabled if Analog waveform is specified in the Plot Type box Specifies the scaling values and uni
323. ptions oe C Transfer function Start data output 0 M Default J DEDE PRINT step 20u Default Output all data Output at PRINT step Real time noise C Enable realtime noise Define Monte Carlo and multi step analysis C Enable multi step Define Selected mode None Cancel Define Snapshots Advanced Options Help To set up the analysis first check the box on the right according to which analysis you wish to perform You can select more than one but usually it is easier to do just one at a time The following describes the most commonly used modes and how to set one up Transient The most useful and general mode First the bias point is found Then the circuit is simulated over a fixed time interval in steps of varying size according to circuit activity The circuit may contain any number of time varying voltage and current sources stimuli see Circuit Stimulus on page 56 to simulate external signals test generators etc Usually you only need to specify the Stop time specified at the top of the dialog box For information on the remaining options see Transient Analysis on page 170 DC Device Sweep A DC device sweep will sweep a specified device over a defined range and compute the DC operating point of the circuit at each point This allows for example the DC transfer function of the circuit to be plotted Note that all reactive elements are ignored in DC sweep T
324. ptions variable 333 BuildSymbolLibs options variable 333 Bus connections see Schematic bus connections C CachePathSymbols options variable 333 CancelOnFocusLost option variable 333 Capacitor editing values 137 initial condition 138 353 User s Manual non linear 146 sweeping 176 Catalog files 164 ALL CAT 164 OUT CAT 164 USER CAT 164 CatalogExtension option variable 345 CentreFreq function 271 Chokes 133 see also Inductor Choose analysis dialog 168 Circuit rules 55 Circuit stimulus 56 Clipboard copying graphs 258 copying schematics 78 Colours customising 348 Command history 281 Command line 281 maximum line length 282 Commands full list 290 ComponentExtension option variable 345 Configuration settings 324 Core materials 133 cos function 301 Current plotting 67 68 Current source controlled 140 fixed 139 sweeping 177 CursorDisplay option variable 334 Cursors graph 242 247 see also Graph cursors CurvePrintWidth option variable 334 CurveWeight option variable 334 D DataExtension option variable 345 DataGroupDelete 334 dB function 301 plotting 68 214 219 DC sweep analysis 180 decscript property 105 354 DefaultLib option variable 323 DefaultLib options variable 334 Defining keys 350 DefKey command 290 Defining menus 350 DefMenu command 292 DelMenu command 294 DefKey command 290 Deleting schematic wires 72 DelMenu command 294 DevConfigFile options variable 335 Device power p
325. quares function See page 310 Chapter 11 Command and Function Reference tan real complex Return tan of argument in radians Use tan_deg if the argument is in degrees Truncate real real real Data Start x Value End x value Returns a portion of the input vector with defined start and end points Interpolation will be used to create the first and last points of the result if the start and end values do not coincide with actual points in the input vector Arguments 2 and 3 define the beginning and end of the vector Example Suppose we have a vector called VOUT which was the result of a simulation running from 0 to 1mS We want to perform some analysis on a portion of it from 250uS to 750uS The following call to Truncate would do this Truncate VOUT 250u 750u If VOUT did not actually have points at 250uS and 750uS then the function would create them by interpolation Note that the function will not extrapolate points before the start or after the end of the input vector unitvec real Returns a vector consisting of all 1 s Argument specifies length of vector vector real Returns a vector with length specified by the argument The value in each element of the vector equals its index XFromY real real real real Input vector Y value Interpolation order 1 or 2 Direction of slope 0 any 1 ve 1 ve Returns an array of values specifying the horizontal location s where the specifi
326. quently restore a deleted item use Add Item see below 283 User s Manual 284 To Move a Menu Item or Sub menu Select the item then use the up and down arrows key to move as required If you wish to move a menu item to a different sub menu you should remove it as described above then add it again using Add Item see below To Add a New Menu Item You can add a previously removed menu item to a new location or you can create a completely new menu item In both cases select the location within a sub menu and press Add Item To add a previously removed menu select Add Existing and choose an item in the left hand pane This pane will be empty if you have not previously removed any menu items This could be in a previous session as deleted items are always remembered To add a new item press Add New then enter the required values For Name enter the name of the menu as you would like to see it in the menu itself Use the amp character to denote underlined letters used to denote Alt key short cuts E g amp My Menu will be displayed My Menu and will be activated with Alt M For Command String you must enter a valid SIMetrix command Typically this would call a user defined script but you may also enter primitive commands or a list of primitive commands separated by semi colons See the Script Reference Manual for full details To add a separator to the sub menu press Add Separator To Create a Ne
327. quire tightening of the simulation tolerance parameters In most cases just reducing RELTOL relative tolerance is sufficient This can be done from the Options tab of the Choose Analysis Dialog Simulator Choose Analysis For a more detailed discussion on accuracy see the chapter Convergence and Accuracy in the Simulator Reference Manual Chapter 9 Graphs Probes and Data Analysis Frequency Response Calculations These must find the passband for their calculations Like rise and fall a histogram approach is used to find its approximate range and magnitude Further processing is performed to find its exact magnitude Note that the algorithms allow a certain amount of ripple in the passband which will work in most cases but will fail if this in excess of about 3dB Note that the frequency response measurements are general purpose and are required to account for a wide variety of responses including those with both high and low pass elements as well as responses with band pass ripple This requirement compromises accuracy in simpler cases So for example to calculate the 3dB point of a low pass response that extends to DC the OdB point is taken to be a point midway between the start frequency and the frequency at which roll off starts A better location would be the start frequency but this would be inaccurate if there was a high pass roll off at low frequencies Taking the middle point is a compromise which produces good but not ne
328. r As with SIMetrix you can also enter the raw netlist command in the F11 window The contents of this window remain synchronised with the Choose Analysis dialog box settings so you can freely switch between the two methods Transient Analysis SIMPLIS transient analysis is similar to SIMetrix transient analysis 201 User s Manual 202 Setting up a Transient Analysis 1 Select menu Simulator Choose Analysis 2 Select Transient check box on the right 3 Select Transient tab at the top Enter parameters as described in the following sections Analysis Parameters Stop Time Start Saving Data Plot data output Start plotting data Stop Plotting Data Number of Plot Points The finish time of a transient analysis The data required to create plots will start being output at this time Start plotting data under Plot data output has a similar function but is subtly different See below for details This is the time at which the process of creating plot data is started This is similar to Analysis parameters gt Start saving data but subtly different The process of generating plot data in SIMPLIS is a two stage operation When the simulation is running it saves internal state data known as switching instance data The switching instance data then has to be transformed to actual plot data This latter process is known as Post Simulation Processing or PSP Analysis parameters gt Start saving dat
329. r between the emitter of Q3 and the base of Q2 There isn t room to add this tidily at present so first we will move a few components to make some space Proceed as follows 1 In the schematic window drag the mouse with the left key pressed over the region shown by the dotted lines below 37 User s Manual Q3 Q2N2222 gt Amplifier Outpu i 2 2k I R3 l ut CLOAD ai cag Q2N2222 i 100p V2 R5 Q2 AC 1 0 Pulse 0 100nj 0 10n 10n 5u 2N22221 470 l R4 2 7k R1 I fi l 1K 5V R6 I i l As you drag the mouse a rectangle should appear 2 Release the mouse The area enclosed will turn blue The blue wires and components are said to be selected To move them 3 Place the cursor within one of the selected components V1 say then press and hold the left mouse key 4 Move the mouse to the right by two grid squares then release the left key 38 Chapter 2 Quick Start 5 Unselect by left clicking in an empty area of the schematic This is what you should now have 6 Wire in the capacitor C1 as shown below using a similar procedure as for the resistor R6 Amplifier Output CLOAD Q2 Q2N2222 InF is obviously far too
330. r fixed probes to plot simulation results during the course of the run Also you must manually load the simulation data when the run is complete Starting an Asynchronous Run 1 Select menu Simulator Run Asynchronous Note a simulation status box appears similar to the box used for synchronous runs but with an additional Activity box at the bottom Any messages generated by the simulator will be displayed here 2 When the simulation is complete you must load the data manually The name of the file to load will be displayed in the command shell when the simulation starts Select menu Fil Data Load Temporary Data to load data file You will be able to cross probe the schematic used to run the analysis in the normal manner once this file is loaded Pausing and Aborting Asynchronous Runs To pause press the Pause button Note that you can load the data generated so far after pausing the run as described above To abort a run press the Close button Running an Analysis on a Netlist You can run an analysis on a netlist created by hand or perhaps with a third party schematic entry program To run a netlist in synchronous mode select the command shell menu Simulator Run Netlist then locate the netlist file To run a netlist in asynchronous mode select the command shell menu Simulator Run Netlist Asynchronous then locate the netlist file See Running Analyses in Asynchronous Mode above for further information about
331. r spectrum 222 impedance 220 in hierarchical designs 233 old results 239 random 67 218 234 busses 226 current 68 dB 68 fourier 222 functions 219 phase 68 voltage 68 results from earlier run 239 362 Index Properties see Schematic properties PSP 202 PSpice schematic translator 117 configuring 117 opening schematics 118 symbol libraries 118 PSpiceIniPath option variable 323 339 PulseWidth function 275 R Random Probes 67 Range function 309 re function 309 ReadLogicCompatibility 295 real function 309 Real time noise analysis 187 RebuildConfig option variable 339 ref template property keyword 110 Ref function 309 ref property 104 151 RELTOL 193 repeat template property keyword 110 RepeatPlace option variable 339 Reset command 296 Resistor additional parameters 137 editing values 137 non linear 146 sweeping 177 Restarting transient analysis 173 Rise function 276 Rise time calculating 248 252 RMS calculating 248 function 310 RMS function 310 rnd function 310 RootSumOfSquares function 310 Rotating schematic components 54 71 Running simulation 65 basic steps 53 hierarchical designs 65 S Saturation 133 363 User s Manual SaveRhs command 296 Saving graphs 260 simulation data 262 Schematic annotating 78 bus connections 77 add 77 in hierarchy 83 probing 226 ripper 77 wiring 77 checking 79 copy to clipboard 78 creating 70 displaying bias point 260 editing 71 adding free text
332. rator may wish to customise the way SIMetrix is configured when started by each user In this case you may manually create a base sxprj file or alternatively a common skeleton that SIMetrix will use to create this file Your base sxprj file can if desired be completely populated with all required settings and configured to disable auto configuration altogether Alternatively you can inhibit some of the auto configuration operations while allowing others to proceed normally There are five settings that control auto configuration These must be placed in the Options section of the base sxprj file The settings are shown in the following table Option Name RebuildConfig Possible Values Default in bold true false BuildPreferenceSettings askmigrate true BuildAssociations BuildModelLibs BuildSymbolLibs false ask true false ifempty merge no ifempty merge no Chapter 13 Sundry Topics Description Auto configuration proceeds if this is set to true Auto configuration automatically sets this to false on completion Build user preference settings askmigrate ask the user whether he wants to migrate settings from an earlier version if available true Build default values false do nothing Build file associations Windows only ask ask the user if he wants file association to be performed true file associations performed unconditionally false file associations not performed I
333. rchical block the pin name must match the names of the module ports on the schematic which it represents If the symbol is to be used for an existing sub circuit from say a model library the pin names are not important and you can choose any suitable name The pin names do not need to match the node names in the sub circuit definition Text Location Justification If the pin name is visible this specifies its alignment Hidden Check this box if you do not wish the pin name to be visible on the schematic Vertical The pin s label will be displayed vertically if this is checked Attributes Font style Select font style to use for a visible pin name There is a choice of 8 styles Schematic fonts are explained on page 348 Placing Multiple Pins To place more than one pin select menu Property Pin Place Pin repeated You will be prompted to supply a Base pin name which will be used to compose the actual pin name SIMetrix will append a number to this name to make the pin name unique The first number used will be 0 unless you append the Base name with a number in which case your appended number will be used as the starting point For example if you supplied a Base name of DATA the first pin placed will be called DATAO the second DATA etc assuming there aren t already pins of that name on the sheet If you supplied a base name of DATA2 the first pin you place will be called DATA2 the second DATA3 etc Editing Multiple Pins
334. rest and press control N For currents place the cursor over the component pin and press control I Bias Annotation in SIMPLIS The above apply to operation in both SIMetrix and SIMPLIS modes When in SIMPLIS mode the dc values displayed represent the results at time 0 For AC analysis this will be the time 0 value for its associated POP analysis Bias Annotation Display Precision By default bias annotation values are displayed with a precision of 6 digits To change this select command shell menu File Options General then edit the value in box Bias Annotation Precision in the Schematic sheet Bias Annotation and Long Transient Runs If you are running a long transient analysis and plan to use bias annotation extensively you might like to set a simulator option that will make this process more efficient The simulator option is OPTIONS FORCETRANOPGROUP This forces a separate data group and separate data file to be created for the transient analysis bias point data Unless tstart gt 0 bias point data is usually taken from t 0 values The problem with this approach is that to view a single value the entire vector has to be loaded from the data file to memory This isn t a problem if the run is only a 100 points or so but could be a problem if it was 100 000 points It can take a long 261 User s Manual time to load that amount of data By specifying this option the bias point data is stored separately and only a single val
335. riable may also be swept using the parameter sweep mode for the swept analyses and stepped for multi step analyses Complete documentation on this subject can be found in the Simulator Devices chapter of the Simulator Reference Manual Below are brief details of how to use expressions with a schematic based design We explain this with an example Example Chapter 5 Components Feet 2 2 Pl freq C1 alpha 2 2 PI gt alpha R1 AC 10 v1 C1 alpha apne 7 vouT I The above circuit is that of a two pole low pass filter C1 is fixed and RI R2 The design equations are R1 R2 2 2 pi f 0 Cl alpha C2 C1 alpha alpha 4 where freq is the cut off frequency and alpha is the damping factor Expressions for device values must be entered enclosed in curly braces and To enter expressions for components we recommend that you use shift F7 not F7 as for normal value editing and remember the curly braces shift F7 provide literal editing of a devices value and bypasses the intelligent system employed by F7 and the Edit Part menu Before running the above circuit you must assign values to the variables This can be done by one of three methods 1 With the PARAM control placed in the netlist 2 With Let command from the command line or from a script If using a script you must prefix the parameter names with global 3 By sweeping the value using the parameter mode of a swe
336. ries SLB files directly See PSpice Schematics Translation on page 117 for more details Pressing the Add button will open a file select dialog box but note that it has two additional buttons at the top left called User and System Pressing these buttons will take you straight to the user symbols directory and the system symbols directory respectively 115 User s Manual 116 Uninstalling Libraries Select the library file you wish to uninstall from the Library Files box then press the Remove button Note that this does not delete the file Changing Search Order When searching for a particular symbol the library files are searched in the order in which they are listed in the Library Files box To change the order use the Up and Down buttons Moving Symbols To move an individual symbol to a new category simply pick it up with the mouse and drop it onto the new category You can move a symbol to a new library by dropping the symbol onto a library file in the Library Files box You can move more than one symbol at a time by picking up a complete category Copying Symbols To copy a symbol within a library select the symbol in the Symbols box then press the Copy button or use the right click menu Copy Symbol Enter a new user name for the symbol It isn t usually necessary to change the internal name To copy symbols to a new library use the same drag and drop procedure as for moving but hold the control
337. rimaries and secondaries You can specify up to ten of each Define turns ratio Select Winding Lists all windings except primary 1 Ratio to Primary 1 Enter the turns ratio with respect ratio primary 1 Inductance and coupling Primary 1 Inductance Self explanatory Inter primary coupling Coupling factor between primaries Inter secondary coupling Coupling factor between secondaries Primary secondary coupling Coupling factor from each primary to each secondary 135 User s Manual 136 This method of implementing an ideal transformer is not totally general purpose as you cannot arbitrarily define inter winding coupling factors If you need a configuration not supported by the above method you can define any ideal transformer using ideal inductors and the Mutual Inductance device The SIMetrix version is explained in the next section For the SIMPLIS equivalent see the SIMPLIS reference manual Coupling Factor The standard user interface for both saturable and ideal transformers provide only limited flexibility to specify inter winding coupling factor In the majority of applications coupling factor is not an important issue and so the standard model will suffice In some applications however the relative coupling factors of different windings can be important An example is in a flyback switched mode supply where the output voltage is sensed by an auxiliary winding In this instance best performance is achieved if the sense
338. robing 220 diff function 301 Differential voltage probing 69 DigAxisHeight option variable 335 Digital analog converter 141 Disconnecting schematic wires 54 72 DisplaySimProgressMessage option variable 335 Distortion calculating 250 252 DOCSPATH system path 321 Duplicate models 166 Duty cycle calculating 249 Duty function 271 E EchoOn option variable 335 Editor option variable 335 EXEPATH system path 321 exp function 301 Exporting data 278 ExportRawFormat 335 Expressions 154 Extensions file 330 F Fall function 272 Fall time calculating 249 Fall time calculating 252 Fast start for transient analysis 172 ferrite 133 FFT function 302 Index 355 User s Manual of selected curve 253 phase 224 plotting 223 File extensions 330 Filter response functions 146 FIR function 302 Flipping schematic components 54 71 Floor function 303 Fonts customising 348 Fourier analysis 222 226 Frequency function 273 sweeping 179 with multi step analysis 196 Functional modelling arbitrary non linear passive devices 146 generic ADCs and DACs 141 generic digital devices 142 laplace transfer function 145 non linear transfer function 143 Functions full list 298 G Global nets 84 Global pins 84 GlobalCatalog options variable 335 Goal functions 268 full list 268 270 Graph cursors 242 247 changing styles 245 displaying 243 freezing 244 moving 243 moving to peak or trough 243 readout 245 Graph toolbar 213 GraphE
339. rrents at the top level i e not in a sub circuit to be output For hierarchical designs data for all signals for the whole circuit are output To restrict the output you can use the KEEP control in the F11 window see Manual Entry of Simulator Commands on page 65 to restrict what data is output E g KEEP noi top will result in only top level voltages and digital signals being output KEEP nov noi top will prevent all data except digital signals and the reference vector time frequency etc from being output With some or all data output inhibited using KEEP as described above you can add keep symbols to the schematic to select specific voltages or currents to be saved For information on the comprehensive features of KEFP please refer to the Simulator Reference Manual To Add a Voltage Keep to a Schematic 1 Select menu Place From Symbol Library 2 Select device Connections gt Keeps Voltage Keep 3 Place device on desired schematic net To Add a Current Keep to a Schematic 1 Select menu Place From Symbol Library 2 Select device Connections Keeps Current Keep 3 Place device directly on a device pin Parameters and Expressions 154 You can specify both device and model parameters using an arithmetic expression containing user defined variables The variables may be defined using the PARAM simulator control which must be placed in the netlist or globally in a script using the Let command A va
340. rresns 81 Navigating Hierarchical designs 81 Table of Contents Placing Full vs Relative Path cseeeeee 82 Connecting Busses in a Hierarchy eese 83 Global Nets s2c0 cccceceseeesd tee ttee deere hatiecsseeeescovdeee 84 Global PINS 21 04ssciecne es Shae eles 84 Passing Parameters Through a Hierarchy 85 Missing Hierarchical BIOCKS eeteeeeceeesteeeeneees 85 Printings renee a ere crac eet ererre rere 86 Printing a Single Schematic Sheet ee 86 Printing a Hierarchical Schematic 86 File Operations sez isoionissi ienn 86 SDAVINIG EAEE fe TEE EE T 86 Exporting Schematic Graphics 00 0 0 ee eeeeeeeeeees 86 Exporting to Earlier Versions of SlMetrix 0 00 87 ASCII Tormat ccis Accvseeecteiesst Anes a 87 Creating Schematic Symbols Overview seee 88 Symbol Generato ez cavicsssceccsesceieedhaeesoned cache sogceceteseteseivteess 88 To Create a NeW Symbol 0 0 0 ceeceeeeteeeenteeenneeeees 89 To Create a New Symbol From an Existing One 89 Symbol Shaper aiiai 89 E A E EE 90 Netlist Order cecon e 90 Symbol Pin Order c sseeceedecsesececdeepeeessadeesoteenedere 90 Modifying Pins 0 0 0 eee eeseeeeeeeeseeeeseneeeesneeeeenaeeeeenees 90 Proper eS e a rear prea aeaee eataa aperia areeni 90 Placing Symbol on Schematic eeee 93 Graphically Editing Generated Symbols 93 Graphical Symbol Editor 0 0 eee eeeeeeeeeeeeeeeeeeeenneeeeeeees 93 NOLE
341. rt is not specified the vector is arranged in order of ascending y values i e smallest y value first largest last Otherwise they are organised in ascending x values Chapter 11 Command and Function Reference Minimum real complex real real Vector Start x value End x value Returns the smallest value found in the vector in the interval defined by start x value and end x value If the vector is complex the operation will be performed on the magnitude of the vector norm real complex Returns the input vector scaled such that the magnitude of its largest value is unity If the argument is complex then so will be the return value ph real complex phase real complex Returns the phase of the argument ph is identical to phase and return the phase in degrees The ph and phase functions produces a continuous output i e it does wrap from 180 degrees to 180 degrees phase_rad real complex Identical to ph and phase functions except that the result is in radians Range real complex real real Vector Start index Default 0 End index Default vector length 1 Returns a vector which is a range of the input vector in argument 1 The range extends from the indexes specified by arguments 2 and 3 If argument 3 is not supplied the range extends to the end of the input vector If neither arguments 2 or 3 are supplied the input vector is returned unmodified re real complex real real complex
342. rty and a value value property Additionally simulator symbols should also have a model property For subcircuits this should have the value X Hierarchical blocks do not need a value property 4 Enter required properties See below for more information For each property select the location for the text of the property You may also choose to have the property not visible This is usual for the model property 5 Press Add Properties You Need to Add Full documentation on properties is given in Properties on page 102 The following describes the properties you need when making a symbol to use as a simulator primitive subcircuit or hierarchical block 91 User s Manual 92 Property name Function Ref property Value property Model property Simulator property This is the component reference e g U1 R3 etc This would conventionally be a letter or letters followed by a question mark When you place the component on the schematic the question mark will be replaced automatically by a number that makes the reference unique If you don t specify a Model property see below the first letter of the reference is important as it defines the type of device This is explained in more detail below This is the device s value or model name including any additional parameters For a resistor this might be 12k for an op amp LM324 or for a bipolar transistor Q2N2222 The value property must be prese
343. running asynchronous analyses Transient Analysis 170 In this mode the simulator computes the behaviour of the circuit over a time interval specified by the stop time Usually the stop time is the only parameter that needs specifying but there are a number of others available Setting up a Transient Analysis 1 Select menu Simulator Choose Analysis 2 Select Transient check box on the right Chapter 7 Analysis Modes 3 Select Transient tab at the top Enter parameters as described in the following sections Transient Parameters Enter the stop time as required Note that the simulation can be paused before the stop time is reached allowing the results obtained so far to be examined It is also possible to restart the simulation after the stop time has been reached and continue for as long as is needed For these reasons it is not so important to get the stop time absolutely right You should be aware however that the default values for a number of simulator parameters are chosen according to the stop time The minimum time step for example You should avoid therefore entering inappropriate values for stop time Data Output Options Sometimes it is desirable to restrict the amount of data being generated by the simulator which in some situations can be very large You can specify that data output does not begin until after some specified time and you can also specify a time interval for the data Output all data Output
344. rve Markers Placing To place a curve marker select menu Annotate Add Curve Marker A single curve marker should appear in the right hand margin of the graph Chapter 9 Graphs Probes and Data Analysis Moving To move it place the mouse cursor at the arrow head you should see the cursor shape change to a four pointed arrow then left click and drag to your desired location When you release the marker it will snap to the nearest curve Moving Label To move the text label alone place the mouse cursor to lie within the text then left click and drag You will notice the alignment of the text with respect to the arrowed line change as you move the text around the arrow You can fix a particular alignment if preferred by changing the marker s properties See below Deleting First select the marker by a single left click in the text The text should change colour to blue Now press delete key or menu Annotate Delete Selected Object Editing Properties Double click the marker s label or select then menu Annotate Edit Selected Object The following dialog will open F lt Edit Curve Marker x Properties Edit Label Text Alignment eourve label Automatic Left Bottom Font Items enclosed with are symbolic values and are s resolved when displayed E g Zcurve label resolves to the name of the curve to which the marker points See help for details Label Text of the marker s label curve label
345. ry File Saves the symbol to the library file specified in the File box This would usually have a SXSLB extension Save to Component File Saves the symbol as a component to the file specified in the File box This would usually have the extension SXCMP Component files are used for hierarchical schematics and contain a schematic and a symbol representing it in the same file When you save a symbol to a component file only the symbol portion of it will be overwritten If it contains an embedded schematic that schematic will remain unchanged See Hierarchical Schematic Entry Save to Current Schematic Only The symbol will be saved to the currently selected schematic only and will not be available to other schematics File Library or component file name see above Press Browse to select a new file Creating a Symbol from a Script In very early versions of SIMetrix this was the only method of creating schematic symbols With the introduction of the graphical symbol editor this method is no longer needed except for specialised applications such as automatic symbol creation This technique is employed for some of the schematic s functional blocks and also for parts such as transformers For full documentation on how to create a symbol from a script refer to the Script Reference Manual This is available as a PDF file on the install CD and can also be downloaded from our web site Properties 102 Overview Properties
346. s d phase y 1 dx lax where y is the supplied vector and x is its reference The GroupDelay function expects the result of AC analysis where y is a voltage or current and its reference is frequency This function will yield an error if its argument is complex and has no reference Histogram real real Arg1 Vector Arg2 Number of bins Creates a histogram of argument with the number of bins specified by argument 2 The bins are divided evenly between the maximum and minimum values in the argument Histograms are useful for finding information about waveforms that are difficult to determine by other means They are particularly useful for finding flat areas such as the flat tops of pulses as these appear as well defined peaks The Histogram function is used in the rise and fall time scripts for this purpose Users should note that using this function applied to raw transient analysis data will produce misleading results as the simulation values are unevenly spaced If you apply this function to simulation data you must either specify that the simulator outputs at 303 User s Manual 304 fixed intervals select the Output at interval option in the Choose Analysis dialog box or you must interpolate the results using the Interp function see page 305 Iff real any any Result if test TRUE Result if test FALSE Arg2 and Arg3 must both be the same type If the first argument evaluates to TRUE i e no
347. s 118 LiMItatiONS eis eee isssee snes aE 118 Using Schematic Editor for CMOS IC Design 119 MOSFET Symbols seeen 119 Automatic Area and Perimeter Calculation 120 Editing the MOS Symbols seeen 121 Further Information c ccccecescceeceeeeeeeeeeeeeseeaeeeeeeeaea 121 How Symbols are Stored secsec 121 Summary of Simulator Devices 122 Components Numbered Components cceceeeeeceeeeeeeeeneeeeeeeees 125 Numbered Components in SIMPLIS n 126 SPICE to SIMPLIS Conversion cceceeees 127 Generic COMpPONENtS eeeeeeeeeeeeeeeeteneeeeeeeeeeteeeeenes 131 Saturable Inductors and Transformers 133 Ideal Transformers ccccccececeeeeeeeeeeeeeeeeeaeeeeees 135 Coupling Factor iise onide oian 136 Mutual INdUC OTS iin aeni 136 Resistors Capacitors and Inductors 0 137 Potentiometer siitin 138 Lossless Transmission Line ceceeeeeeeeees 139 Lossy Transmission Line 139 Fixed Voltage and Current Sources 0 0 0 eee 139 Controlled SOUrCES 0 ccccccecceceeeeeeeeeeeeeeseeneeeeees 140 Voltage Controlled Switch cceeeeeseeeeeeeeeee 140 Switch with Hysteresis c cceceeeeeeeeeeeeeeeeees 141 Generic ADCs and DACS cccceceeeeeeeeeetteeeees 141 Generic Digital Devices 142 Functional Blocks Overview seeeeee 142 Non linear Transfer Function
348. s defined See User Defined Key and Menu Definitions on page 350 Details of some of the available commands are given in Command and Function Reference on page 289 The remainder are documented in the S Metrix Script Reference Manual Command History A history of manually entered commands is available from the drop down list select arrow to the right of the command line Some other commands entered via menus or from a script may also be placed in the command history Message Window Various messages may be displayed in the message window below the command line These include command progress errors warnings and listing outputs The text in the window may be copied to the clipboard using a context sensitive menu activated by the right mouse button 281 User s Manual Multiple commands on one line You can place multiple commands on the same line separated by a semi colon This is the only way a menu or key can be defined to execute more than one command Scripts SIMetrix features a comprehensive scripting language Full details of this can be found in the Script Reference Manual This is available as a PDF file on the install CD A hardcopy version is also available for an additional charge Command Line Editing The command line itself is a windows edit control The cursor keys home and end all work in the usual way You can also copy control C cut control X and paste control V text There is
349. s or grids other than the Main axis left empty by this operation will also be deleted Hiding and Showing Curves A curve may be hidden without it actually being deleted This is sometimes useful when there are many curves on a graph but the detail of one you wish to see is hidden by others In this instance you can temporarily remove the curves from the graph To hide a curve or curves select it or them then press the Hide selected curves button To show it or them again press the Show selected curves button Re titling Curves You can change the title of a curve by selecting it then pressing the Name curve button This will change the name of the curve as displayed in the legend panel Above main graph area and below toolbar 241 User s Manual Highlighting Curves You can highlight one or more curves so that they stand out from the others This is useful if there are many overlapping curves displayed To Highlight Curves 1 Select the curves you wish to highlight then press H or menu Curves Highlight Selected Curves To Un highlight Curves 1 Select the curves you wish to un highlight then press U or menu Curves Unhighlight Selected Curves To Unhighlight All Curves 1 Select menu Curves Unhighlight All Curves Graph Cursors Overview Graph cursors can be used to make measurements from waveforms In their default configuration they consist of two dimensioned crosshairs as shown below
350. s so you can freely switch between the two methods The Choose Analysis dialog box does not support sensitivity and pole zero analysis so these methods must be set up using the F11 window 168 Chapter 7 Analysis Modes Running Simulations Overview Once an analysis has been set up using the procedures described in this chapter a simulation would normally be run in synchronous mode perhaps by selecting the Simulator Run menu In synchronous mode you cannot use any part of the program while the simulation is running There are also other methods of running a simulation You can run a simulation for a netlist directly and you can also run in asynchronous mode These are explained in the following sections Starting Pausing and Aborting Analyses Starting an Analysis To start a simulation in normal synchronous mode use the Simulator Run menu press the F9 key or press the Run button on the Choose Analysis Dialog box shown above A dialog box will show the status of the simulation Pausing an Analysis You can pause the simulation by selecting the Pause button on the simulator status dialog box To restart select the Resume button the Pause button changes name when simulation pauses or the Simulator Resume menu item When a simulation is paused you can carry on using the program as if the simulation had completed This includes plotting results of the simulation completed so far If you decide you do not wish to continue the r
351. s such as word processors or drawing programs You can do this via the clipboard windows only see Copying Graphics to the Clipboard above or by writing out to a file To export waveform graphics to a file select the graph menu File Save Picture then select the format of your choice using the Save as type drop down box The choices are 1 Windows Meta File EMF and WMEF This is only available in Windows versions Nearly all windows applications that support graphics import will accept this format Note that this is a scalable format and therefore suitable for high resolution printing 2 Scalable Vector Graphics svg This is a relatively new format and is not supported by many applications However it is the only scalable format available in Linux 259 User s Manual 3 Bitmap default image size png jpg bmp These are available on all platforms are widely supported by graphics applications but these are not scalable formats and so do not offer good quality when printed using high resolution printers PNG is the default format if you do not choose a file extension and generally this is the format that provides the best image quality file size trade off To choose JPG JPEG format or BMP windows bitmap format you must explicitly enter jpg or bmp file extensions respectively With this option the image size will match the image size currently displayed on screen If you wish to specify a different image size
352. sarily the lowest frequency in the circuit but the largest frequency for which all frequencies in the circuit are integral harmonics For example if you had two sine wave generators of 1kHz and 1 1KHz the fundamental is 100Hz not 1kHz 1kHz is the tenth harmonic 1 1 KHz is the eleventh You should not specify a fundamental frequency for circuits that have self oscillating elements FFT Interpolation As explained above the FFT method must interpolate the signal prior to the FFT computation Specify here the number of points and the order The number of points entry may be forced to a minimum if a high stop frequency is specified in the Frequency Display section The number of interpolation points required depends on the highest significant frequency component in the signal being analysed If you have an idea what this is a useful trick to set the number of points to a suitable value is to increase the stop frequency value in the Frequency Display section up to that frequency This will automatically set the number of interpolation points to the required value to handle that frequency If you don t actually want to display frequencies up to that level you can bring the stop frequency back down again The number of interpolation points will stay at the value reached If in doubt plot the FFT twice using a different number of points If the two results are significantly different in the frequency band of interest then you should increase the
353. se PSpice to convert them to symbols Chapter 4 Schematic Editor 5 The template properties are converted to the SIMetrix format but with one limitation References to properties that are themselves templates are not supported These are used in some of the standard ABM blocks supplied with PSpice These will need to be manually converted by editing the template property 6 You will not normally be able to cross probe current into a device converted from PSpice The current into the device will be available but the schematic cross probing mechanism won t work without manually editing the symbols and template property 7 PSpice Schematics allows the placement of symbol pins parts and wires off grid The translator will convert these correctly and SIMetrix will display them correctly but they can cause problems if attempting to edit them subsequently SIMetrix itself does not permit the user to place off grid items If off grid parts are identified they will be highlighted and a warning will be displayed Off grid symbols will also resulting in a warning If possible we recommend that these are corrected within the PSpice environment before reading the file into SIMetrix Using Schematic Editor for CMOS IC Design MOSFET Symbols 4 MOSFET symbols are supplied for use in CMOS IC design These are Q2 N channel 3 terminal bulk to VSS nmos_a3_vss_new W 1u L 1u Q1 N channel 4 terminal nmos_a_new J W 1u L 1u Q3 P channel 3 t
354. se tab at the top Enter parameters as described in the following sections Sweep Parameters Start value Stop value Points per decade Number of points Define Noise Parameters Output node Reference node Source name Defines sweep range stop and start values Defines sweep range The number of points of the sweep is defined per decade for a decade sweep For a linear sweep you must enter the total number of points Sets up desired sweep mode See Setting up a Swept Analysis on page 179 This is compulsory It is the name of the circuit node as it appears in the netlist Usually the schematic s netlist generator chooses the node names but we recommend that when running a noise analysis that you assign a user defined name to your designated output node To find out how to do this see Finding and Specifying Net Names on page 80 Optional Output noise is referred to this node This is assumed to be ground if it is omitted Optional Voltage or current source to which input source is referred Enter the component reference of either a voltage or current source Monte Carlo and Multi step Analysis See page 194 See Also NOISE in Simulator Reference Manual Plotting Results of Noise Analysis Refer to Plotting Noise Analysis Results on page 221 Chapter 7 Analysis Modes Example 1 Frequency Sweep restail R2 SUB The result of a noise analysis on the above c
355. ser and per machine basis The same user can start any number of instances of SIMetrix on the same machine and it will be counted as just one license Note however that on Linux each X display is considered as a separate computer for the purposes of counting licenses So for example if you run SIMetrix from the local display and then launch another SIMetrix instance on a remote X server e g VNC two licenses will be required Note that the license server can serve licenses for SIMetrix running on either Linux or Windows regardless of what platform the license server is running Mixed Feature Licenses The license file may list codes for between 1 and 6 types of feature The features are Basic Digital Micron Advanced Rtn Simplis_if Basic is as the name implies the basic feature and is compulsory for the SIMetrix simulator to run The remaining feature names enable functionality as defined in the following table Feature name Functionality Digital Enables event driven digital simulator Micron Enables chip design features e g BSIM3 BSIM4 VBIC Philips models Star Hspice model file compatibility Advanced Enables extended sweep modes Rtn Enables Real Time Noise analysis Simplis_if Enables the SIMPLIS simulator interface Note that this does not enable the SIMPLIS simulator itself By default SIMetrix will attempt to check out all features that are available If you have purchased the same number of licenses f
356. series losses are supported Enter parameters as indicated The absolute tolerance and relative tolerance parameters control the accuracy speed trade off for the model Reduce these values for greater accuracy Fixed Voltage and Current Sources See Circuit Stimulus on page 56 139 User s Manual 140 Controlled Sources There are four types which can be found under menu Place Sources Voltage controlled voltage source or VCVS Voltage controlled current source or VCCS Current controlled voltage source or CCVS Current controlled current source or CCCS These have a variety of uses A VCVS can implement an ideal opamp current controlled devices can monitor current voltage controlled devices can convert a differential signal to single ended They require just one value to define them which is their gain Edit value in the usual way and you will be presented with a dialog similar to that used for resistors capacitors and inductors but without the Parameters button Voltage Controlled Switch This is essentially a voltage controlled resistor with two terminals for the resistance and two control terminals Place one on the schematic with Place Analog Functions Switch Editing using F7 or equivalent menu displays e Choose Switch Parameters On Resistance 1 s Off Resistance 1Meg s On Voltage 3 3 Off Voltage 2 s If On Voltage gt Off Voltage If control voltage gt On Voltage Resistance O
357. set up an AC Frequency Sweep select the AC check box at the right and the AC tab at the top You will need to enter some values in the Sweep Parameters section Chapter 3 Getting Started Transient AC DC Noise TF Options Sweep parameters Start frequency 1 al 4 Decade Stop frequency 1Meg a O Linear Points per decade 25 Mode Frequency The analysis will sweep the frequency over the range specified by Start frequency Stop frequency and Number of points or Points per decade if you select a decade sweep Frequency sweep is just of 6 modes available with AC sweep The Define button allows you to specify one of the others See AC Sweep on page 182 for details Noise Frequency Sweep Like AC analysis Noise analysis is a small signal mode Over a user defined frequency range the circuit is treated as linear about it s DC operating point and the contribution of all noisy devices to a designated output is computed The total noise at that output is also calculated and optionally the noise referred back to an input source may also be computed To set up a Noise Frequency Sweep select the Noise check box at the right and the Noise tab at the top You will need to enter some values in the Sweep Parameters section Transient AC DC Noise TF Options Sweep parameters Start frequency 1k 4 Decade Linear Stop frequency Meg s Points per decade 25 Mode Frequency The analysis will
358. set up the Monte Carlo run Select menu Simulator Setup Multi step 2 In Sweep mode select Monte Carlo 3 Enter the desired number of steps in Number of steps To demonstrate the concepts 10 will be sufficient but usually a Monte Carlo run would be a minimum of around 30 steps 4 Press Run You should see a series of curves build up as the run progresses Tolerances and Distribution Functions Distribution Functions Tolerances are defined using distribution functions For SIMPLIS Monte Carlo there are just three functions available These are defined below Function Name Description GAUSS to Returns a random with a mean of 1 0 and a standard deviation of to 3 Random values have a Gaussian or Normal distribution UNIF to Returns a random value in the range 1 0 tol with a uniform distribution WC tol Returns either 1 0 fo or 1 0 to chosen at random The L and F suffix functions available in SIMetrix Monte Carlo analysis are not available for SIMPLIS operation Initial Chapter 8 SIMPLIS Analysis Modes Lot and Device Tolerances No special provision has been made to implement so called Lot tolerances which model tolerances that track However it is nevertheless possible to implement Lot tolerances by defining a parameter as a random variable Suppose for example that you have a resistor network consisting of 4 resistors of 1k with an absolute tolerance of 2 but the resistors m
359. signifies either or Ellipsis This signifies 1 or more optional multiple entries Fonts Anything that would be typed in is displayed ina fixed width font Command line parameters are in italics Case Although upper and lower cases are used for the command names they are NOT in fact case sensitive Examples OpenGroup text filename Both text a switch and filename a parameter are optional in the above example So the following are all legitimate OpenGroup OpenGroup text OpenGroup run23 dat OpenGroup text output txt DelCrv curve_number One or more curve_number parameters may be given So the following are all legitimate DelCrv 1 2 3 DelCrv 1 289 User s Manual Command Summary Only a few of the approximately 220 available commands are detailed in this chapter and a list is given in the table below Documentation for the remainder is provided in the Script Reference Manual This is available as a PDF file on the install CD and can also be downloaded from our web site Command name Description DefkKey DefMenu DelMenu ListStdKeys OpenGroup ReadLogicCompatibility Reset SaveRhs Set Show UnSet Reference 290 DefKey Define keyboard key Define fixed or popup menu item Delete menu item Write standard key definitions to file Create new group of simulation data from data file Read external logic compatibility tables Release memory used for simulation Cr
360. sing the colour dialog box This is opened using the File Options Colour menu item Select the object whose colour you wish to change then select Edit button to change it The colours you select are stored persistently and will remain in effect for future sessions of SIMetrix Fonts Fonts for various components of SIMetrix may be selected using the font selection dialog box This is opened using the File Options Font menu item Select the item whose font you wish to change the press Edit to select new font Items available are Chapter 13 Sundry Topics Font object name Where font used Associate Model Text Command Line F11 Window Graph Graph Caption Graph Free Text Legend Box Message Window Print Caption Schematic Schematic annotation Schematic caption Schematic free text Schematic user 1 4 View File Window Notes on Schematic Fonts Model display window in associate model dialog box Command line at top of command shell Schematic F11 window used for simulator commands Graph windows Graph Caption objects placed using Annotate Add Caption Graph Free Text object placed using Annotate Add Free Text Graph Legend Box object placed using Annotate Add Legend Box Bottom part of command shell Font used at base of printed schematic and graph Default for schematics Note that the size for all schematic fonts is relative The actual font size used also depends on current
361. sions option variable 332 A abs function 301 ABSTOL 193 AC sweep analysis 182 SIMPLIS 205 ALL CAT 164 AlwaysUseMarkers option variable 332 Analog behavioural modelling laplace 145 non linear 143 Analog digital converter 141 Analysis modes AC sweep 182 choose analysis dialog 168 DC sweep 180 Monte Carlo sweep 179 multi step 194 noise 183 operating point 175 options 192 pole zero 191 real time noise 187 sensitivity 191 SIMPLIS 201 AC 205 Periodic operating point POP 203 205 transient 201 specifying 58 168 sweep modes 176 180 sweeping devices 176 sweeping frequency 179 352 Index sweeping model parameters 177 sweeping parameters 177 sweeping temperature 177 transfer function 188 transient 170 175 restarting 173 transient snapshots 173 AnnoMinSuffix options variable 332 APPDATAPATH system path 321 Application data directory 325 arg function 301 arg rad function 301 atan function 301 AutoStartWire options variable 332 AutoWireEnabled options variable 332 AWAllowRouteThruConnected options variable 332 Axes creating new 237 deleting 238 editing 238 reordering digital 239 selecting 237 AxisPrintWidth option variable 332 B Bandwidth function 270 Bias Point 260 BiasAnnoPrecision options variable 333 BiScriptDir option variable 322 333 Blackman FFT window 226 Bode plot 214 BPBW function 270 BuildAssociations options variable 333 BuildModelLibs options variable 333 BuildPreferenceSettings o
362. so a method of providing the association information in bulk which is advantageous in many cases Procedure There are two stages to installing SPICE models 1 Install the model itself so that the program knows where to look for it This is simply a matter of dropping files or folders on the command shell See Installing Electrical Model below 2 Associate the model s with a schematic symbol This process is often automatic and you don t need to do anything see explanation in the Overview above If this is necessary you will be prompted for the information required See Placing New Model on Schematic below Full Model Installation Procedure The following is the full procedure for installing models including association if required Chapter 6 Device Library and Parts Management Installing Electrical Model 1 Open a suitable file manager program such as windows explorer in Windows systems or Konqueror in KDE Locate the folder where your model files are located Select the items you wish to install You can also install a single file multiple files an entire folder or multiple folders You only thing you can t do is install files and folders at the same time Make sure that the SIMetrix command shell is visible If it is obscured you can bring it to the surface by pressing the spacebar with a schematic or graph selected Pick up the items selected in 2 above and drop them into the message window of
363. specifying the value using a VAR control Add this line VAR r3_value 100 to the F11 window This line defines the value of R3 when a normal single step analysis is run Options The above example illustrates a linear multi step parameter run You can also define a decade logarithmic run and also a list based run that selects parameter values from a list To set up a list run select the List radio button then press Define List Enter the values for the list using the dialog box The Group Curves check box controls how graphs are displayed If unchecked curves for each run will have their own legend and curve colour If checked curves will all have the same colour and share a single legend 207 User s Manual 208 Setting Up a SIMPLIS Monte Carlo Analysis An Example To set up a Monte Carlo analysis you must first define component tolerances This is done by defining each value as an expression using one of the functions Gauss Unif or WC Here is another example Open the same example circuit as above then make the following changes 1 Select R3 press shift F7 then enter the value 100 GAUSS 0 05 Y Select C2 press shift F7 then enter the value 100u GAUSS 0 2 3 Delete the fixed probes on the V1 input and on R1 This is just to prevent too many unnecessary curves being plotted The above will give R3 a 5 tolerance and C2 a 20 tolerance with a 3 Sigma Gaussian distribution Now
364. st Fourier Transform This is an efficient algorithm for calculating a discrete Fourier transform or DFT DFTs generally operate on evenly spaced sampled data Unfortunately the data generated by the simulator is not evenly spaced so it is therefore necessary to interpolate the data before presenting it to an FFT algorithm The interpolation process is in effect the sampling process and the Nyquist sampling theorem applies This states that the signal can be perfectly reproduced from the sampled data if the sampling rate is greater than twice the maximum frequency component in the signal In practice this condition can never be met perfectly and any signal components whose frequency is greater than half the sampling rate will be aliased to a different frequency So if the number of interpolated points is too small there will be errors in the result due to high frequency components being 223 User s Manual 224 aliased to lower frequencies This is the Achilles heel of FFTs applied to simulated data The Continuous Fourier technique described next does not suffer from this problem It suffers from other problems the main one being that it is considerably slower than the FFT Continuous Fourier This calculates the Fourier spectrum by numerically integrating the Fourier integral With this method each frequency component is calculated individually whereas with the FFT the whole spectrum is calculated in one quite efficient operation
365. stored using symbolic constants Automatic path matching is invoked whenever a library is installed Notes for Windows The automatic path matching system will correctly match a drive based path e g h projects proj1 with its mapped UNC path e g server1 c projects proj1 provided the drive based path points to a network share and not a local drive For example if the project fie contains the entry Project serverl c projects projl and server1 c is mapped to the H drive then the file H Projects proj1 cell23 sxemp will be stored as Project cell23 sxemp However if you are actually running SIMetrix from the machine server and server1 c is the share name for the local C drive then C Projects proj1 cell23 sxcmp will not be recognised as equivalent to Project cell23 sxcmp This limitation is due to security restrictions in Windows NT 2000 XP SIMetrix Command Line Parameters A number of command line parameters may be supplied to the SIMetrix binary SIMetrix exe on Windows SIMetrix on Linux when starting the program The full syntax is as follows SIMetrix exe schematic_file s startup_script n c config_location f features schematic_file Path of a schematic file usually with extension sxsch This file will be opened immediately s startup_script Name of script file or command that will be executed immediately after SIMetrix starts hi If specified the schematic_file or and startup_script will
366. surements These measurements have to determine the waveforms pulse peaks A histogram method is used to do this Flat areas of a waveform produce peaks on a histogram The method is very reliable and is tolerant of a large number of typical pulse artefacts such as ringing and overshoot For some wave shapes the pulse peaks are not well enough defined to give a reliable answer In these cases the measurement will fail and an error will be reported Distortion This calculates residue after the fundamental has been removed using an FFT based method This algorithm needs a reasonable number of cycles to obtain an accurate result The frequency of the fundamental is displayed in the message window Note that most frequency components between 0Hz and just before the second harmonic are excluded The precision of the method can be tested by performing the measurement on a test circuit such as v2 5 Sine 0 1m 2k 0 0 v1 5 Sine 01 1k 00 The signal on the pos side of V2 has 0 1 distortion Use V1 as your main test source assuming you are testing an amplifier then after the simulation is complete check that the distortion measurement of V2 is 0 1 If it is inaccurate you will need either to increase the number of measurement cycles or reduce the maximum time step or both You can adjust the amplitude of V2 appropriately if the required resolution is greater or less than 0 1 Note that in general accuracies of better than around 1 will re
367. synchronous using a descriptive language Schematic support for functional blocks is provided by a number of devices under the menus Place Analog Behavioural Place Digital Generic Devices currently provided are shown in the following table Device Description Non linear Transfer Function Based on the arbitrary non linear source This will create a schematic symbol with your specified inputs and outputs You enter the equation to relate them Laplace Transfer Function Based on the S domain transfer function block This will create a schematic symbol with specified input and output You enter an s domain transfer function Non linear Transfer Function Select menu Place Analog Behavioural Non linear Transfer Function This displays 143 User s Manual fl Define Arbitrary Source Expression Use I n for input currents and Nn for input voltages Mintin Inputs Dutouts Single ended voltage Number of input voltages Single ended current Number of l input currents Differential voltage Differential current Specify the number of input voltages and currents you require All voltage inputs are single ended and all input currents are differential In the expression box you must specify an equation relating the output to the inputs In the equation currents are referred to by the label I Vn where n identifies the actual current input 1 is the first top most on the symbol
368. t If you place the probe immediately on an existing schematic wire SIMetrix will try and deduce a meaningful name related to what it is connected to If you place the probe at an empty location its name will be a default e g PROBE1 NODE which won t be meaningful and you will probably wish to subsequently edit it Fixed Current Probes You can place these on a schematic with the single hot key U or with one of the menus Probe Place Fixed Current Probe Place Probe Current Probe schematic popup Probe Current Current probes must be placed directly over a component pin They will have no function if they are not and a warning message will be displayed Fixed Differential Voltage Probes These can be placed using one of the menus Probe Place Fixed Diff Voltage Probe Place Probe Differential Voltage Probe Random Probes Most of the entries in the schematic s Probe menu are for random probing You can probe voltage current differential voltage device power dB phase Nyquist 67 User s Manual 68 diagrams and much more You can also plot arbitrary expressions of any circuit signal and plot signals from earlier simulation runs Just a few of the possibilities to get you started are explained below For a full reference see Random Probes on page 218 Random Voltage Probing 2 3 Select the schematic menu item Probe Voltage Using the mouse place the cursor over the point on the circuit you
369. t Hierarchy Ascend 2 Ifschematic is open it will be brought into view if it isn t it will be opened Placing Full vs Relative Path Components can be placed using their full path or a relative path When placed with a full path the component file is referenced using its full file system path name e g C Projects Proj123 amplifier sxcmp This allows the schematic file that uses the component to be freely moved as long as the component file stays in the same place However if the component file is moved the schematic will no longer be able to locate it When placed with a relative path the component file is referenced with a file system path name relative to the schematic that uses it Most likely the component file will be in the same directory or folder as the schematic and will therefore be referenced by its file name alone E g amplifier sxcmp This allows the schematic file and component file to be moved together to any location but they may not be moved individually Which is used depends on the application If files are always kept in the same directory location it doesn t matter which you use To place a component using its full path Select schematic menu Hierarchy Place Component Full Path Select a component file then place in the normal way To place a component using its relative path Select schematic menu Hierarchy Place Component Relative Path Select a component file then place in the normal way
370. t aj C Protected Inhibits editing of property Absolute a values on schematic aR i vets Font scales linearly with zoom eft Top Lines gt Justiieaton Left Top Sf Cannot use with default font 5 Property text will be C Hidden idan on aches C Show name Display name as well as value VEFA Text will be rotated o Resolve Enable resolution of expression vertical by 90 degress symbolic and special symbols teres tee J This box allows you to define the name value and attributes of the property Note that if the property is not protected the value and attributes can be changed after the symbol has been placed on a schematic using the schematic popup Edit Properties Name Name of property This would usually be one of the special properties documented in Properties on page 102 You can however add any property name you wish to display as text or to provide a special function that you define in a custom script The only restriction is that the name must not contain spaces Value The property s value Don t confuse this with the Value property You can insert a new line by pressing the ENTER key But be careful that if you press the ENTER key accidentally intending to close the dialog that you must delete the erroneously entered new line Text location Define the position of the property s value text on the schematic Auto Absolute When auto is selected the property s value text is positioned Normal
371. t nodelist gt SVALUE gt gt Creates a series combination of components The number in series is determined by the property SERIES Note that the REF keyword returns the component reference appropriately modified by the MODEL property and appended with the sequence number If SERIES 5 REF R1 VALUE 1k and MODEL R and the device is connected to external nodes R1_P and R1_N this is the end result 111 User s Manual 112 R1 1 R1_P 1 1k R1 2 1 2 1k R1 3 2 3 1k R1 4 3 4 1k R1 5 4 R1 N 1k If the num element is empty e g in above example if SERIES property were empty or missing then no output will be made at all The example above can be used for any two terminal component There must however be a SERIES property present on the symbol PARALLEL lt PARALLEL num lt line gt gt Creates a parallel combination of the device described in line For example lt parallel parallel lt lt ref gt lt nodelist gt SVALUE S gt gt creates a parallel combination of components The number in parallel is determined by the property PARALLEL Note that the REF keyword returns the component reference appropriately modified by the MODEL property and appended with the sequence number If PARALLEL 5 REF R1 VALUE 1k MODEL R and the device is connected to external nodes R1_P and R1_N this is the end result R1 1 R1_P R1 N 1k R1 2 R1 _P R1 N 1k R1 3 R1 P R1 N 1k R1 4 R1 P RI N 1k R1 5 R1_P RIN 1k If the num element is empty e
372. t the most recent measurement performed Notes on Curve Measurement Algorithms Some of the measurements algorithms make some assumptions about the wave shape being analysed These work well in most cases but are not fool proof The following notes describe how the algorithms work and what their limitations are All the measurement algorithms are implemented by internal scripts The full source of these scripts can be found on the install CD per Cycle and Frequency Measurements These measurements assume that the curve being analysed is repetitive and of a fixed frequency The results may not be very meaningful if the waveform is of varying frequency or is of a burst nature The cycle measurements calculate over as many whole cycles as possible Each of these measurements use an algorithm to determine the location of x axis crossings of the waveform The algorithm is quite sophisticated and works very reliably The bulk of this algorithm is concerned with finding an optimum base line to use for x axis crossings The per cycle measurements are useful when the simulated span does not cover a whole number of cycles Measurements such as RMS on a repetitive waveform only 251 User s Manual 252 have a useful meaning if calculated over a whole number of cycles If the simulated span does cover a whole number of cycles then the full version of the measurement will yield an accurate result Rise and Fall Time and Overshoot Mea
373. t the schematic menu item Probe AC Noise db Voltage for dB or Probe AC Noise Phase Voltage Using the mouse place the cursor over the point on the circuit you wish to plot Press the left mouse button The new curve will be added to any existing graph if the X axis has the same units Otherwise a new graph sheet will be created Chapter 3 Getting Started Probing dB and Phase for AC Analysis On New Graph Sheet 1 Create an empty graph sheet by pressing F10 or selecting menu Probe New Graph Sheet 2 Proceed as in above section Differential Voltage Probing The schematic menu Probe Voltage Differential allows you to plot the voltage difference between two points When you select this menu click on the schematic twice The first is the signal node and the second the reference node Advanced Probing The menu Probe More Probe Functions provides many more probing functions selectable from a tree structured list More advanced plotting can be achieved with the menu Probe Add Curve This opens a dialog box allowing you to enter any expression and which also provides a range of options on how you wish the graph to be plotted 69 User s Manual Chapter 4 Schematic Editor Schematic Windows and Sheets The schematic editor window is shown below It can display multiple sheets arranged like a notebook with tabs It is also possible to have multiple windows allowing schematic to be compared Creating Schem
374. t to the list file Options are None No Output Brief Only values defined by an expression are output Given The default Values that are explicitly defined are output Full All parameter values are output including defaults Monte Carlo Seed Seed for pseudo random number generator used to generate random numbers for tolerances See Multi step Analyses on page 194 Multi step Analyses 194 Multi step analyses are not available with all versions of the product The analysis modes Transient AC DC Noise and Transfer Function can be setup to automatically repeat while varying some circuit parameter Multi step analyses are defined using the same 6 sweep modes used for the individual swept analyses The 6 modes are briefly described below Note that Monte Carlo analysis is the subject of a whole chapter see Monte Carlo Analysis on page 313 Device Steps the principal value of a device E g the resistance of a resistor voltage of a voltage source etc The component reference of the device must be specified Model parameter Steps the value of a single model parameter The name of the model and the parameter name must be specified Temperature Steps global circuit temperature Parameter Steps a parameter that may be referenced in an expression Frequency Steps global frequency for AC Noise and Transfer Function analyses Monte carlo Repeats run a specified number of times with tolerances enabled As we
375. tail is a parameter that is swept in an AC sweep to plot the gain of the amplifier vs tail resistance at 100kHz Here is the result of the run Gain 100kHz of simple differential amplifier Output V 100 200 400 10k restail 178 Chapter 7 Analysis Modes Note that this analysis mode is not available in standard SPICE or the majority of its derivatives Most offer parameter sweeping but only for DC analysis Frequency Sweeps frequency for the small signal analysis modes namely AC AC Noise and Transfer Function In standard SPICE it is the only sweep mode available for AC and Noise while Transfer Function can not be swept at all Monte Carlo Repeats analysis point for a specified number of times with device tolerances enabled The following graph show the result for the same circuit as shown above but with restail 1k and with a 1000 point Monte Carlo AC sweep This run took 0 6 seconds with a 1 5G P4 Distribution of gain 100KHz Output V The graph shows the variation in gain for 1000 samples Using the histogram feature a statistical distribution of the above can easily be plotted Setting up a Swept Analysis In the AC DC Noise or Transfer Function analysis sheets select the Define button in the Sweep Parameters box This will bring up the following dialog 179 User s Manual e Define Swee
376. talog This may take some time please wait will be displayed At this stage SIMetrix knows where to find our fictitious devices You will find that it also knows about the NPN transistor as the following demonstrates 1 Open an empty schematic 2 Press control G or select menu Place From Model Library You should see window displayed with the caption Select Device 3 Select the Recently Added Models category from the top of list shown on the left hand side 49 User s Manual 50 4 Select SXN1001 from the listed items on the right hand side This is what you should see FA Select Device Recently Added Models a SRNTOOT All User Models 5x041000 All Models Analog MSI Analog switches Buffers Comparators Digital Flip flops Digital MSI Digital Analog interfaces Diode Drivers Gates Gates An IGBTs Instrumentation Amplifiers Line Drivers P Palla Sa Pn A Macatee oe j D SIMetrix BuildNewApps Install Source E xamples Release Common T utorials T utorial3 mod Category NPN 5 Press Place to place the device on the schematic Without you having to tell it SIMetrix already knew that the SXN1001 is an NPN transistor This is because it is a primitive device defined using a MODEL control Such devices are built in to the simulator and SIMetrix can determine the part type simply by reading the MODEL control in TUTORIAL3 MOD
377. tart the license manager l cd usr local flexim 2 lmgrd c licensefile where licensefile is the name of the license file To stop the license manager 1 lmutil lmdown q You may wish to install a run level script to start up the license manager automatically when the machine is booted or enters a particular run level However this is really a system issue and is beyond the scope of this manual Starting SIMetrix Network Version When you start SIMetrix for the very first time it will be necessary to enter details of the license server You will be presented with a dialog box asking for the name of the license server Chapter 1 Introduction a Get License Server Network License Details Please enter the name of the computer that is running the network license server This is the unique name assigned to every machine on a network If you do not know this ask your system administrator You can also enter the IP address of the server in this box If required you can also enter a TCP port number When asked for the license server name press Advanced and enter the required port number For more information on ports and the circumstances when you would use them see Using TCP Ports on page 23 Using TCP Ports In most situations you can ignore this section Situations where you need to know about ports are 1 SIMetrix takes a long time to acquire a license 2 You are accessing the lic
378. tected for the instances listed To fix the problem remove the protection on this property You will need to open the symbol in the symbol editor to do this In order to apply back annotation in a generic fashion SIMetrix needs to modify the SIMPLIS TEMPLATE property but cannot do so if it protected hence the error message You shouldn t get this error with any standard symbols from the SIMetrix v5 library or later but you may get it with your own symbols or symbols from an earlier library Editing Back annotated Initial Conditions How you change the value of an back annotated initial condition depends on the device If the device already has a user editable initial condition then simply use the standard method With capacitors and inductors this is simply done using F7 or the Edit Part menu With some other devices the initial condition value may be found in the Edit Additional Parameters menu For devices that do not have user editable initial conditions you should use the Edit Additional Parameters menu This applies to most subcircuit models and to all hierarchical blocks How Does it Work The initial condition file specifies the value of initial conditions for each device that requires them This information must then be applied to each schematic instance in an appropriate manner Two basic approaches are used to apply the initial condition values depending on the device namely the specialised method and the generic method
379. ter 9 Graphs Probes and Data Analysis Paste Data from the Clipboard SIMetrix can plot curves using tabulated ASCII data from the clipboard The format is the same as used for exporting data See Copy Data to the Clipboard above for more details Using the Internal Clipboard The menus Edit Copy Edit Cut and Edit Paste all use the internal clipboard These menus are intended to allow the moving or copying of curves to new graphs Note that these menus do not use the system clipboard at all See above sections for details on how to copy and paste from the system clipboard The internal clipboard uses an efficient method for transferring curves that uses very little memory even if the curve is large Also if you copy a curve the data itself is not copied internally the two curves just reference the same data This makes copying a memory efficient operation To Move a Curve to a New Graph Sheet 1 Select the curve or curves you wish to move 2 Select menu Edit Cut 3 Either create a new graph sheet to receive the new curves use F10 or switch to an existing graph sheet 4 Select menu Edit Paste To Copy a Curve to a New Graph Sheet 1 Select the curve or curves you wish to move 2 Select menu Edit Copy 3 Either create a new graph sheet to receive the new curves use F10 or switch to an existing graph sheet 4 Select menu Edit Paste Exporting Graphics You may export schematic graphics to other application
380. the average power dissipation over a specified time To display the average power dissipation over the analysis period 1 Select menu Measure Mean This should display a value of 517mW This is the average power over the whole analysis period of 1mS You can also make this measurement over any period you select using the cursors as described below 1 Zoom in the graph at a point around 100uS i e where the power dissipation is at a peak 2 Switch on graph cursors with menu Cursors Toggle On Off There are two cursors represented by cross hairs One uses a long dash and is referred to as the reference cursor the other a shorter dash and is referred to as the main or measurement cursor When first switched on the reference cursor is positioned to the left of the graph and the main to the right 45 User s Manual 3 Position the cursors to span a complete switching cycle There are various ways of moving the cursors To start with the simplest is to drag the vertical hairline left to right As you bring the mouse cursor close to the vertical line you will notice the cursor shape change See Graph Cursors on page 242 for other ways of moving cursors 4 Press F3 or select analysis menu Measure More Functions From the tree list select Measure Transient Mean Cursor Span i Select Operation Gr measure AC E Other S Transient Distortion Duty Cycle Fall Time E Frequency Per Cyc
381. the label is the only way then you should be aware of how the positions of property text are defined In SIMetrix property positions can be defined in one of two ways namely Auto and Absolute Most of the standard symbols have their properties defined as Auto This means that SIMetrix chooses the location of the property on a specified edge of the symbol and ensures that it doesn t clash with other properties on the same edge Auto properties are always horizontal and therefore easily readable The position of Absolute properties is fixed relative to the symbol body regardless of the orientation of the symbol and location of other properties When the symbol is rotated through 90 degrees absolute text will also rotate Absolute properties are intended for situations where the precise location is important such as in a title block When a visible property on a symbol is moved by the method described above it and all other visible properties on that symbol are converted to Absolute locations This is the only way that the positions of all properties can be preserved This means that once you move a single property on a component it and all other properties will rotate with the symbol For this reason it is better not to move property text until the orientation of the symbol has been finalised Wiring Overview SIMetrix offers both manual and smart wiring methods In smart mode you select the start and end points and SIMetrix will find a suitab
382. the names listed in Options on page 325 For options of type Boolean use form1 For others use form 2 See Also Options on page 325 Unset on page 298 Show Show file filename append filename noindex noHeader plain force clipboard names names width width expression expression Displays the value of an expression This command can be used to export data from the simulator in ASCII form See Data Import and Export on page 277 for more details file filename If specified outputs result to filename The values are output in a format compatible with OpenGroup text See OpenGroup on page 294 append filename As file except that file is appended if it already exists noindex If the vector has no reference the index value for each element is output if this switch is not specified noHeader If specified the header providing vector names etc will be inhibited plain If specified no index as noindex and no header as noHeader will be output In addition string values will be output without enclosed single quotation marks force File specified by file will be unconditionally overwritten if it exists 297 User s Manual clipboard Outputs data to system clipboard names names Semi colon delimited string providing names to be used as headings for tabulated data If not specified the vector names are used instead width width Page width in co
383. tio to primary 1 1 Coupling factor 1 Define core Select core t ae Senice z elect core type Manual entr is EFDIDSFSA25 J Sit y O cm Le 237 2 inches Core material 3F3 O metres Ue 66 D Primary ind 29 127uH Saturation current 3 782064 3 Close the box then place the inductor 4 Runa new simulation 5 Select the graph sheet that displayed the inductor current by clicking on its tab at the top of the graph window Now select schematic menu Probe Current in Device Pin and left click on the left hand inductor pin You will notice the peak current is now in excess of 45A This is of course because the inductor is saturating You can also measure the peak power over cycle 1 Select the graph sheet with the power plot then select Probe Power In Device 2 Zoom back to see the full graph using the button 3 Zoom in on the peak power 4 Position the cursors to span a full cycle The cursors are currently tracking the first power curve This doesn t actually matter here as we are only interested in the x axis values If you want to make the cursors track the green curve you can simply pick up the cursor at its intersection with the mouse and drag it to the other curve 5 We now have two curves on the graph so we must select which one with which we wish to make the measurement To do this check the box as shown File Edit Cursors Annotate Curves Axes View Measure PRAA aD EE m v Power Q1
384. tion But note there is a potentiometer device that automates this procedure see Potentiometer on page 138 In order to solve the circuit the simulator has to calculate the voltage at every node at every time point Disk space is cheap and plentiful so SIMetrix saves all these values Chapter 2 Quick Start as well as the device currents Not all simulators do this some require you to state in advance what you want saved After the run is complete you can then randomly probe the circuit to look at any voltage current or device power over the analysis time period You can also place fixed probes on the circuit before running the analysis which will cause the waveform at that point of the circuit to be automatically be displayed while the simulation is running or optionally after its completion Some of the other analysis modes are AC analysis which performs a frequency sweep DC sweep which ramps a voltage or current source and noise analysis which calculates total noise at a specified point and which components are responsible for that noise Tutorial 1 A Simple Ready to Run Circuit This tutorial demonstrates a basic simulation on a ready to run to circuit All you need to do is load the circuit and press F9 to run it We will then make a few changes to the circuit and make some extra plots This tutorial demonstrates the basic features without having to get into the details of setting up a simulation Proceed as follows 1
385. tion Summary segti aai 298 Function Reference eneninda en 301 abs real compleX eeeeeeeerreerrerrerrrens 301 arg real COMPIeX eee eeeeeeeeeeeeeeeeeeeeeeeeeenteeeeeaees 301 arg_rad real COMpleX esenee 301 atan real COMPIeX cece eeeeeeeeeeeeneeeeeenteeeenaees 301 cos real COMPIeXx 2 25 cieee eeeesteeedceeddcnre ee eneeeeees 301 db real complex iiien 301 Olff real 2 432 vale Aan ee sen ieee 301 exp real COMPIOX c cecsseecssacetesecceeeoteeeeseesenseeeee 301 fit real String jiis 302 FIR real real reall c c 302 FIOOr Real dsn en r at 303 GroupDelay real complex ceee 303 Histogram real real l enn 303 Iff real any ANY n e 304 WR real real real ccccseeeeeeeseeeeeeeeeseeeeeeeees 304 im real complex imag real complex eee 305 INTE Q TOAl sonia ncaa need Gece iae eee 305 Interp real real real real ec eeeeeeeeeeeeeees 305 ISCOMPIEX ANY 0 ee eeeeeeeeeeeeeeeeeeeeeeeeeeneeeteeaeeeeneeeenaa 306 Table of Contents ISnigth ANY siccseceeseccecedvctnessencen detect itevbecdenentedaercees 306 In real COMPIeX 0 eee eeeeeeeeeeeeeeeeeeenneeteeeeeenteeeee 306 log10 real complex log real complex 306 mag real complex magnitude real complex 307 maxidx real COMPIeX seereis 307 Maxima real real String esseceesseeesteeeees 307 Maximum real complex real real c eee 308 mean real COMPIeX ee
386. tion has many more features such as Random variation of device model parameters Support for matched devices Log file creation Seed selection to allow repeated runs with same randomly applied values Component Tolerance Specification In this section we will only cover the simple case of how to specify tolerances on devices at the schematic level SIMetrix has much more comprehensive features for specifying tolerances aimed primarily at Integrated Circuit design For complete documentation on tolerance specification please refer to the Monte Carlo Analysis chapter of the Simulator Reference Manual Note that Monte Carlo analysis is not available with the SIMPLIS simulator Setting Device Tolerances To select individual device tolerances proceed as follows 1 Select component or components whose tolerances you wish to be the same You can individually select components by holding the control key down and left clicking on each Select menu Monte Carlo Set Selected Component Tolerances and enter tolerance in the dialog box You may use the symbol here if you wish so 5 and 0 05 have the same effect Note this is the only place that is recognised you can t use it netlists or models 315 User s Manual 316 If all the resistors or all the capacitors in a circuit are to have the same tolerance select either Monte Carlo Select All Capacitor Tolerances or Monte Carlo Select All Resistor Tolerances
387. tion is running You can also find the current group by selecting Simulator Change Data Group and noting which group is highlighted in the dialog box Here is an example In tutorial 1 the signal marked with the Amplifier Output probe is actually called Q3_E The latest run group is called tran4 We want to plot the output subtracted from the output for the previous run The previous run will be tran3 So we type at the command line Plot tran4 q3_e tran3 q3_e This will create a new graph sheet If you wanted to add the curve to an existing graph use the Curve command instead of Plot For more details on data groups the Plot command and the Curve command please refer to the Script Reference Manual This is available as a PDF file on the install CD and may also be downloaded from our web site A hardcopy version is also available for an additional charge Chapter 9 Graphs Probes and Data Analysis Curve Operations Selecting Curves E PSU Waveforms Selected BEX File Edit Cursors Annotate Curves Axes View Measure Plat BRAA Gam HR EER SLSR m E IL3 P v1 p m C 2P Y2 Click hereto lt lt select tran2 I L3 P Y1 this curve y2 Y1 S2 P V KL3 P IA TimekSecs 20Secsidiv x 2 07761kSecs y 16 3644V Deleting Curves To delete a curve or curves select it or them then press the Erase selected curves button Any axe
388. tion of the PSPICE INI file which PSpice uses to store symbol library locations Proceed as follows Select menu File Options General Select File Locations tab Double click the item PSpice inifile Locate the file PSPICE INI This is usually at the root folder for PSpice e g C Program Files Orcad PSpice PSPICE INI Press Open when you have found the file Bee The above assumes you are using version 9 of PSpice Earlier versions stored their settings in a similar manner but the file name was different and in a different location 117 User s Manual 118 For example MSIM INI located in the windows directory Note we have only tested version 9 2 and the evaluation version 8 0 Some earlier versions used different inifile section names and in these cases the file will need to be manually edited For more information see the on line help topic Schematic Editor gt gt PSpice Schematics Translation If you don t have PSpice If you do not have PSpice on your system then you will need to create a PSPICE INI file that contains the location of the PSpice symbol libraries Note that PSpice schematics do not contain local copies of their symbols unlike SIMetrix so the symbol libraries are essential to perform any schematic translation For information see the on line help topic Schematic Editor gt gt PSpice Schematics Translation Reading PSpice Schematics Once the translator has been configured simply open the PSpice sc
389. to be changed Electrical Model SxX0A1000 opamp Negative supply Positive supply e ee we ee EE Define Symbol for SXO41000 Choose Category for SXO 41000 New Category Auto Create Symbol sr MERTE r From C Program Files sIMetrix53 examples Tutorial3 mod line 14 Al 3 First specify a suitable category for the device In this case it is an operational amplifier so select Op amps from the drop down box labelled Choose Category for SXOA1000 4 Next define a symbol for this part Under Define Symbol for SXOA1000 select Operational Amplifier 5 terminal We have not quite finished yet Our new op amp has the wrong pin out for the schematic symbol The pin order for the symbol is shown in the third box down on the right and is as follows Pin name Function INP Non inverting input INN Inverting input VSP Positive supply VSN Negative supply OUT Output The text at the bottom of the dialog box shows the actual subcircuit definition Fortunately it has been annotated with the function of each of the sub circuit s terminals This is in fact usually the case with third party models As you can see the output terminal is in the wrong place We can change the pin order using the Pin order up and down buttons 1 Select out in the pin order box 51 User s Manual 2 Click twice on the up button so that it is positioned be
390. to create symbols 1 Use the graphical symbol editor see page 93 2 Use the symbol generator see page 88 3 Create manually with a script For most applications using the graphical symbol editor is the most appropriate method The symbol generator was originally developed for a very early version of SIMetrix as a temporary measure before a full graphical editor became available It isn t as flexible as the graphical editor but with practice it is possible to create symbols very rapidly with this tool For that reason the symbol generator continues to be available The manual approach using a script is described in the Script Reference Manual Symbol Generator 88 Select menu item Symbol Editor Symbol Generator This will open symbol generator dialog as shown below Chapter 4 Schematic Editor fl Symbol Definition Name Catalog Style Pin Definition Properties Name and Catalog Internal Name 4D8170 408170 User Name x Category AnalogAmplifiers Buffers Comparators v Style Rectangle Triangle Current Symbol 4D8170 To Create a New Symbol 1 Select the New button 2 Enter a description for symbol as you wish it to appear in the dialog opened with the schematic popup All Symbols The symbol also requires a unique name which may not contain spaces This name is used internally by SIMetrix 3 Enter a catalog You can use an existing one or create a new o
391. to make them unique This option must be used with care Don t use it unless you are very clear about what it will do This function will restore properties according to the local symbol definition stored in the schematic This won t necessarily be the same as the global definition in the symbol library For more information see How Symbols are Stored on page 121 Template Property 106 Overview The template property provides a method of customising the netlist entry for a schematic component Normally a single line is created in the netlist for each schematic component except F and H devices which are defined by two lines The line is created according to the values of various properties most importantly the ref model and value properties If however a template property is specified this system is bypassed and the netlist entry is defined by the value of this property The template property value can contain a number of special keywords and characters that will be substituted during the netlist creation Values that can be substituted include node names pin names and the value of any property Chapter 4 Schematic Editor There are three template keywords new for version 4 that define multiple lines to implement series or and parallel combinations ladder networks or arrays of devices Template Property Format The netlist entry for a device with a template property will be the literal text of the template property s va
392. to schematic 165 indexes 166 installing 49 158 removing 161 SPICE to SIMPLIS conversion 127 model property 104 151 ModelExtension option variable 345 Module port 81 Monte Carlo analysis 313 analysing results 319 359 User s Manual distributions 317 example 313 plotting single curve 319 running 317 setting seed 194 318 sweep 179 317 tolerance device 315 matching 316 model 316 Moving schematic components 72 MRUSize option variable 337 Multiple schematic placement 79 N Navigating hierarchical designs 81 netname property 105 Nets global 84 NewModelLifetime option variable 337 node template property keyword 109 nodelist template property keyword 109 nodename template property keyword 109 NoEditPinNamesWarning option variable 337 NolInitXaxisLimits option variable 337 Noise analysis 183 plotting results 221 real time 187 NoKeys option variable 337 NoMenu option variable 338 norm function 309 NoStopOnError option variable 338 NoStopOnUnknownParam option variable 338 Nyquist plots 219 O OldUserCatalog option variable 338 OmitAsciiRevision option variable 338 OpenGroup command 294 OpenIntro option variable 338 Operating point analysis 175 viewing results 260 Options 325 345 bus probes 227 colours 348 360 Index dialog box 326 fixed probe 215 fonts 348 SIMPLIS 205 simulator 192 variables full list 331 345 GroupPersistence 240 Set command 297 UnSet command 298
393. tool works directly within the schematic environment and may be used in a similar manner to other parameterised devices such as the parameterised opamp However there is also an option to save a particular model to the device library and so making it available as a standard part Creating Soft Recovery Diode Models 1 Select menu Place Create Model Soft Recovery Diode You will see this dialog box Ca Create Diode Model DC Forward bias spec vdi 500m ld1 10m Al d2 700m ld2 1 s Reverse recovery specification Capacitance IF Forward current 1 a Ci0 Capacitance 100p aj at zero bias IRM Peak reverse curent 500m a a Save options ana 50Meg Save to schematic symbol Tr Recovery time 100n a Save to model library Parameters define a soft recovery characteristic d Tris the time to recover to 37 of the peak Device name reverse current from the zero crossing 2 Enter the required specification in the DC Forward bias spec Reverse recovery specification and Capacitance sections See below for technical details of these specifications 3 Select Save to schematic symbol if you wish to store the specification and model parameters on the schematic symbol This will allow to you to modify the 147 User s Manual 148 specification later If you select Save to model library then the definition will be written to a library file and installed in the parts library This will make the new
394. trix may also import data in a tabulated ASCII format This feature may be used to display data from a spreadsheet allowing for example a comparison between measured and simulated data As well as the system clipboard SIMetrix also uses an internal clipboard to which graph curves may be copied This provides an efficient method of moving or copying curves to a new graph sheet Copy Data to the Clipboard 1 Select the graphs you wish to export 2 Select the menu Edit Copy ASCII Data The data will be copied in a tabulated ASCII format The first line will contain the names of the curves while the remaining lines will contain the curves data arranged in columns Copying Graphics to the Clipboard Note that this feature is not currently available in the Linux environment There are three different ways a graph can be copied to the clipboard Use the menus under Edit Copy Graphics These are detailed below Colour Copies graph to clipboard in full colour The curve legends identify the curves using coloured squares similar to how the graph is displayed on the screen Monochrome Copies graph to clipboard in monochrome Curves are distinguished using varying markers and line styles Curve legends distinguished curves with a straight line example Colour with markers Copies graph to clipboard in full colour but also differentiates curves using markers and line styles Curve legends distinguished curves with a straight line example Chap
395. trols schist aa nine 165 Drag and Drop to Schematic eee eeeeeeeeeeeees 166 Library Diagnostics eee eeeeeeeeeneeeeeeeeeeeeeeees 166 Local Models inann niei eei 166 Library Indexing Mechanism cceeeeseeeeeees 166 Duplicate Model Names sneer 166 Chapter 7 Analysis Modes Running Simulations cece eseeeeeeeceeeeneeeeeneeeeeeees 169 OVNE W sii Hie he ied a a aaa ae 169 Starting Pausing and Aborting Analyses 169 Running Analyses in Asynchronous Mode 170 Running an Analysis on a Netlist eee 170 User s Manual Transient Analysis serce inrsin niinen 170 Setting up a Transient AnalySis 0 cece 170 Restarting a Transient RUN seeren 173 Transient Snapshots 0 0 00 cece eeeeeeeeeeeeeenneeeeeeees 173 Operating POU vs sekevacnccscbes cescccebescesntsctersunccnevnnteesteenemspes 175 SWEEP Modes iisi oiid eoo iei 176 Device Sweep ssessesssssseseossrrrnsretrtresreennerestrne neee 176 T6mperature c c0e ae siie gaa 177 Model Parameter 177 Paramete tices seteontcoecdied cc sed tee Beatie n 177 FREQUENCY 25 22 2052 ee eee ce anette recee are aR 179 Monte Carlosi ia iaaa aaan EAEEREN aa 179 Setting up a Swept Analysis 179 DG SWOOP iiia eiii eri in naei 180 Setting up a DC SWEEP 00 eee eeeceeeeeeenneeeeneeees 180 EX MM ple sitroen terii a 181 AC Sweep ii nianna io aii iE 182 Setting up an AC SWe p esseeiesieereeerrrre 182 Example sicchiviel sed
396. ts See File Locations section of options dialog above for more info Default ask See Auto Configuration Options on page 346 Default ifempty See Auto Configuration Options on page 346 Default askmigrate See Auto Configuration Options on page 346 Default ifempty See Auto Configuration Options on page 346 Default false If true SIMetrix will cache symbolic paths Default True on No Windows False on Linux When true interactive actions are cancelled when the window focus is lost This can cause problems if the environment is set up with Point to give focus as moving the mouse outside the active window then cancels the user s action Point to give focus is available on Linux systems 333 User s Manual 334 Name CursorDisplay CurvePrintWidth CurveWeight DataGroupDelete DefaultLib Type Text Numeric Numeric Text Text Description User interface support Default Graph Controls Options initial graph cursor readout dialog display Graph Display on graph only StatusBar Display on status bar only Both Display on both graph and status bar Default 0 5mm Options Width of printed graph dialog curves in mm See also GridPrintWidth Default 1 Options Sets the line width in pixels dialog of graph curves Note that although widths greater than 1 are clearer they normally take considerably longer to draw This does ho
397. ts for analog waveforms Range Offset Units Peak peak value used for display Analog display offset A value of zero will result in an analog display centred about the x axis Select an appropriate unit from the drop down box Plotting an Arbitrary Expression If what you wish to plot is not in one of the probe menus SIMetrix has a facility to plot an arbitrary expression of node voltages or device currents This is accessed via one of the menus Probe Add Curve or Graphs and Data Add Curve Selecting one of these menus brings up the Define Curve dialog box shown below Define Curve Sheet Pl Define Curve Expression ag x Available vectors Curve label Define Curve Axis Graph Options Axis Scales Axis Labels O XY Plot Left click on schematic to insert voltage shift left for current Separate multiple values with Edit Filter Subcircuits All Signal type All Wildcard filter text Chapter 9 Graphs Probes and Data Analysis Expression Y Enter arithmetic expression This can use operators and as well as the functions listed in Function Summary on page 298 To enter a node voltage click on a point on the schematic To enter a device pin current hold down the shift key and click on the device pin in the schematic Both voltages and currents may also be selected from the Available Vectors box Any entries made in
398. ts in parentheses and separate with a comma E g Frequency VOUT 1000 5 94260997 0 002837811 1004 61579 5 94260997 0 00285091 1009 252886 5 94260996 0 002864069 1013 911386 5 94260995 0 002877289 1018 591388 5 94260994 0 00289057 1023 292992 5 94260993 0 002903912 279 User s Manual 280 1028 1032 1037 1042 1047 016298 761406 528416 317429 128548 vana 94260992 94260991 9426099 94260989 94260988 0 002917316 0 002930782 0 00294431 0 0029579 0 002971553 Chapter 10 The Command Shell Chapter 10 The Command Shell PS SiMetrix SIMPLIS Command Shell Joe Eile Simulator SIMPLIS Graphs and Data Help Execute command Welcome to SIMetrix SIMPLIS Drop down list for command history Bh B amp D Command line Message window Command Line The command line is at the top of the command shell See diagram above The vast majority of operations with SIMetrix can be executed from menus or pre defined keys and do not require the use of the command line However a few more advanced operations do require the use of the command line From the command line you can run a script or an internal command You can also define a new menu to call a script command or series of commands In fact all the built in menu and keys are in fact themselves defined as commands or scripts These definitions can be changed as well as new one
399. tween inn and vsp This is what you will now have E Associate Symbol with Model SX0A1000 STEP 1 Select a suitable category for this part IF you can t find one press New Category and enter a new category of your choice STEP 2 Select a suitable symbol for this part Select a symbol from the drop down box or press Auto Create Symbol to create a new one Choose Category for 5X0A1000 Unassigned Define Symbol for SXOA1000 Operational Amplifier 5 terminal New Category Auto Create Symbol 52 Pin order FAKAJ If selecting an existing symbol you must make f f sure that the pin order matches the model definition shown below Press Help for assistance x1 If you use Auto Create Symbol the pin order will not need to be changed Edit Pin Names Electrical Model SX041000 From C Program Files sIMetrix53 examples Tutorial3 mod line 14 Al opamp Negative suppl SSE Osiris 1 Output Inverting pi Non inv input 3 Press OK You will now find our op amp listed under the Op amps category in the parts browser Notes You will not always need to execute the above procedure to associate models and symbols even for subcircuit devices SIMetrix is supplied with a data base of over 30000 devices that are already associated These are devices for which SPICE models are known to be available from some thir
400. ty Core Material Model Details The models for saturable components can be found in the file cores lb Most of the models are based on the Jiles Atherton magnetic model which includes hysteresis effects The MPP models use a simpler model which does not include hysteresis These models only define a single inductor To derive a transformer model the user interface Chapter 5 Components generates a subcircuit model that constructs a non magnetic transformer using controlled sources The inductive element is added to the core which then gives the model its inductive characteristics The model does not currently handle other core characteristics such as eddy current losses nor does it handle winding artefacts such as resistive losses skin effect inter winding capacitance or proximity effect Ideal Transformers Ideal transformers may be used in both SIMetrix and SIMPLIS modes Note that SIMPLIS operation is more efficient if the coupling factors are set to unity To define an ideal transformer select the menu Place Passives Ideal Transformer This will open the following dialog box e Define Ideal Transformer Configuration Define windings Primaries il Select winding Sec 1 1 Secondaries 1 Ratio to primary 1 1 Inductance and coupling Primary 1 D a Inter secondary 1 z j inductance coupling Inter primary a Primary secondary 1 coupling coupling Configuration Specify the number of p
401. u always make a copy of the standard symbols and save them with a new name in your own symbol library Once you have your copied version you can edit it to suit your IC process In most applications you will probably only need to edit the VALUE property See next paragraph Editing VALUE property The VALUE property defines the model name and all the device s parameters except length width and the multiplier M The standard VALUE property defines just the model name and this defaults to N1 for NMOS devices and P1 for PMOS devices You should edit these to match the model name used in your process In addition as described in Automatic Area and Perimeter Calculation above you can append the VALUE property with other parameters such as AD AS etc and define these as expressions relating width using W or and length using L To Edit the Default Values of L and W Edit the L and W properties as appropriate To Edit the Hidden Node for 3 Terminal Devices The hidden bulk node for three terminal devices is defined by the BULKNODE property This defaults to VSS for NMOS devices and VDD for PMOS devices Further Information How Symbols are Stored When a symbol is placed on a schematic a copy of that symbol definition is stored locally This makes it possible to open the schematic even if some of the symbols it uses are not available in the symbol library However if you edit a symbol definition for a schematic that is s
402. ue needs to be read from the file This is much more efficient Future versions may set this option by default Saving Data 262 Saving the Data of a Simulation The simulator usually saves all its data to a binary file stored in a temporary location This data will eventually get deleted To save this data permanently select menu File Data Save You will be offered two options Move existing data file to new location This will move the data file to location that you specify and thus change its status from temporary to permanent As long as the new location is in the same volume disk partition as the original location this operation will be very quick However if the data is from the most recent simulation SIMetrix needs to unhook it in order to be able to move the file This will make it impossible to resume the simulation if paused or restart the simulation transient only Note that if you specify a location on a different volume as the original data then the file s data has to be copied and for large data files this will take a long time Make new copy This makes a fresh copy of the data This option does not suffer from the drawbacks of moving the file but if the data file is large can take a very long time Restoring Simulation Data Select menu File Data Load Navigate to a directory where you have previously saved data files You can also reload data from temporary files using menu File Data Load
403. uit conditions Temperature 27 Initial condition force res Ohms List file output Monte Carlo seed C Enable C Expand subcircuits Parameters Given v Cac Default CI DC Sweep 4 Default CI Noise C Transfer function co peop V Default 4 Default M Default Tolerances Relative Tolerance Current Tolerance Voltage Tolerance Circuit Conditions Temperature Initial Condition Force Resistance Controls the overall accuracy of the simulation The default value is 0 001 and this is adequate for most applications If you are simulating oscillator circuits it is recommended to reduce this to 0 0001 or lower Increasing this value will speed up the simulation but often degrades accuracy to an unacceptable level Sets the minimum tolerance for current It may be beneficial to increase this for circuits with large currents Sets the minimum tolerance for voltage It may be beneficial to increase this for circuits with large voltages Circuit temperature in C Initial conditions apply a voltage to a selected node with a force resistance that defaults to 1Q This option allows that force resistance to be changed 193 User s Manual List File Output Expand subcircuits If checked the listing of expanded subcircuits will be output to the list file This is sometime useful for diagnosing problems Parameters Controls the level of model and device parameter outpu
404. uit s switching cycle During each run SIMPLIS expects to see valid trigger conditions However if there is a fault in the design of the circuit or a fault in the definition of the trigger conditions it is possible that none will be detected The Max period prevents SIMPLIS from carrying on indefinitely in such an event Advanced POP Options Press the Advanced button for more POP options Convergence Sets the convergence criteria for the periodic operating point analysis The convergence criteria is satisfied when the relative change in each state variable between the start and end of a switching cycle is less than this parameter Iteration limit Sets the maximum number of iterations for the periodic operating point analysis Number of cycles output After a successful POP analysis and if there is no transient analysis specified SIMPLIS will generate the steady state time domain waveforms for an integral number switching cycles This option sets the number of cycles Use snapshot from previous transient analysis If checked POP is instructed to take advantage of the last data point of a previous transient simulation assuming the circuit and the initial conditions remained the same between the two Output POP progress AC Analysis Chapter 8 SIMPLIS Analysis Modes simulation runs If checked the progress of the POP solution will be output to the data file for plotting etc This is useful for debugging AC is a sm
405. ull span Peak peak over span defined by cursor positions Rise time of first rising edge in waveform measured at 10 and 90 points Chapter 9 Graphs Probes and Data Analysis Transient measurements Rise Time First edge 20 80 Rise Time First edge Custom Rise Time Cursors define edge 10 90 Rise Time Cursors define edge 20 80 Rise Time Cursors define edge Custom Fall Time First edge 10 90 Fall Time First edge 20 80 Fall Time First edge Custom Fall Time Cursors define edge 10 90 Fall Time Cursors define edge 20 80 Fall Time Cursors define edge Custom Duty Cycle Full Access from menu More Functions menu More Functions menu More Functions menu More Functions menu More Functions Toolbar menu Fall Time menu More Functions menu More Functions menu More Functions menu More Functions menu More Functions menu More Functions menu More Functions Description Rise time of first rising edge in waveform measured at 20 and 80 points Rise time of first rising edge in waveform measured at user defined points Rise time of edge defined by cursor positions measured at 10 and 90 points Rise time of edge defined by cursor positions measured at 20 and 80 points Rise time of edge defined by cursor positions measured at user defined points Fall time of first falling e
406. ults for this type of circuit You will still get sensible results without checking this option they will just be a little better with it For more information see Convergence and Accuracy chapter in the Simulator Reference Manual If you have any graph windows open you should now close them Once you have loaded or entered the circuit press F9 or use the schematic Simulator Run menu to start the simulation This will take somewhat longer than the previous tutorial but still less than 1 second on a 2 8G Pentium 4 This is the graph you will see 43 User s Manual 44 Output V 0 0 2 0 4 0 6 0 8 1 Time mSecs 200uSecs div The circuit is the switching stage of a simple step down buck regulator designed to provide a 3 3 V supply from a 9V battery The circuit has been stripped of everything except bare essentials in order to investigate power dissipation and current flow Currently it is a little over simplified as the inductor is ideal More of this later We will now make a few measurements First the power dissipation in Q1 1 Create an empty graph sheet by pressing F10 2 Select schematic menu Probe Power In Device Left click on Q1 This is what you should see Chapter 2 Quick Start Power Q1 W Time mSecs 200uSecs div This shows a peak power dissipation of 200W although you are probably more interested in
407. un there is no need to explicitly abort it You can just start a new run in the normal way If you do this you will be asked if you would like to resume the pending run If you answer No the pending run will be automatically aborted and the new run started Aborting an Analysis There is actually never a need to explicitly abort an analysis If you decide you do not wish to continue a run just pause it as described above Pause is the same as abort except that you have the option to change your mind and restart Nevertheless there is an abort facility Simply select the Simulator Abort menu When you abort a run you will not be able to restart it There is just one benefit of aborting a run instead of pausing it When an analysis is aborted the simulator frees up the memory it needed for the run Note that this does not happen after a run completes normally If you need to free up simulator memory after a normal run completes type Reset at the command line Not available with SIMetrix Intro 169 User s Manual Running Analyses in Asynchronous Mode In asynchronous mode the simulation runs in the background and you are free to carry on using the SIMetrix environment for entering schematics or viewing results from previous analyses Because the simulation is running in the background it is necessary for the simulation process to be detached from the front end environment and for this reason it is not possible to use GRAPH o
408. uncate function described on page 311 This selects data over a given X range so you can apply a goal function to work on only a specific part of the data Primitive Functions The following primitive functions may be used as goal functions Not all actually return a single value Some return an array and the result would need to be indexed Maxima is an example Chapter 9 Graphs Probes and Data Analysis Name Description Page Maxima real real string Returns array of all maximum turning 307 points Maximum real complex Returns the largest value ina given 308 real real range Mean real complex Returns the mean of all values You 308 should not use this for transient analysis data as it fails to take account of the varying step size Use Mean 1 instead Mean 1 real real real Finds the true mean accounting for 308 the interval between data points Minima real real string Returns array of all minimum turning 308 points Minimum real complex Returns the largest value ina given 309 range RMS1 real real real Finds RMS value of data 310 SumNoise real real real Integrates noise data to find total 310 noise in the specified range XFromy real real real Returns an array of X values ata 211 real given Y value YFromX real real real Returns an array of Y values at a 312 given X value User Defined Functions The following functions are defined using the user defin
409. unctions are available that perform a computation on a complete curve to create a single value By applying one or a combination of these functions on the results of a multi step analysis a curve of the goal function versus the stepped variable may be created This feature is especially useful for Monte Carlo analysis in which case you would most likely wish to plot a histogram We start with an example and in fact it is a power supply whose load response we wish to investigate Example The following circuit is a model of a hybrid linear switching 5V PSU See Work Examples HybridPSU Svpsu_v1 sxsch R12 12 c7 470 C vi 1004 5 D2 A i x2 Nee w Y 1R1 R7 R13 a2 IDEAL 0 5 x BC547 100k Ble ae J BC547 E1 R6 LT107 ai o 330u 100k 1 p35 L1 nT o 1MEG oY aT T ji R5 820k L 100u F ay T Lin R1 cs 1 100K 1 Ce Sro Re vout 26u_l 260u L co 1u pulse 0 iload 0 03 1m j c8 T c2 y 7r C1 12 270k 2 1K R10 R9 oe oe R15 R16 R14 R2 o3 L 100 ce 1 oo a s b I2 provides a current that is switched on for 1mS after a short delay A multi step analysis is set up so that the load current is varied from 10mA to 1A The output for all runs is 263 User s Manual 264 12 pos V 4 9 4 94 4 9 2 pos iload 1 28 30 32 34 36 38 40 Time mSecs 2mSecs
410. use With Windows you can use the LMTOOLS program to find this information This is located on the CD at flexlm windows Click on the System Settings tab With Linux you must use the Imutil command line utility as described below This utility is also available for Windows To use Imutil open a terminal window DOS prompt on Windows at the license server and cd to the FLEXIm directory Type lmutil lmhostid Omit the on Windows This will return the 12 digit Ethernet address If you have more than one ethernet adapter it might return more than one address If so the license can be locked to any of them but you should advise us which one you want to use One of the addresses may be a removable adapter for example which might not always be present Its best to run the utility when any removable or temporary adapters are disabled or disconnected If you are using a FLEXid dongle either supplied by us or from another software vendor using the FLEXIm manager then type lmutil lmhostid flexid Email the license information to support catena uk com Once we have the above information we can issue a license file for the features you have ordered 25 User s Manual 26 Using the License Server Once the license server is installed and running any machine on the network will be licensed to run SIMetrix Licenses will be granted up to the number that have been ordered Note that licenses are counted on a per u
411. use cursor shape change to an up down arrow Press left mouse key and drag 3 Drag and drop In this mode the cursor is picked up and moved without tracking any curve It can be dropped to any location and will then snap to the nearest curve To use this method place the mouse cursor at the intersection of the crosshairs You will see the cursor shape change to a four pointed arrow Press left key and drag to new location You can also move the reference cursor in left right mode using the right mouse button Moving Cursors along a Curve You can move a cursor to a peak or trough using the hot key defined in the following table Key Function F5 Move main cursor to next peak shift F5 Move main cursor to previous peak F6 Move main cursor to next trough shift F6 Move main cursor to previous trough 243 User s Manual 244 Key Function F7 Move reference cursor to next peak shift F7 Move reference cursor to previous peak F8 Move reference cursor to next trough shift F8 Move reference cursor to previous trough These operations can also be accessed from the graph menu Cursors Move Hiding Cursors You can temporarily hide all or some of the displayed cursors Menu Cursors Hide Show All has a toggle action and will hide all cursors if all cursors are currently displayed and vice versa If some cursors are visible and some are hidden you will be presented with an option to hide all cursors or show all cursors
412. use next option 4 Bitmap specify image size png jpg bmp As 3 above but you must explicitly define the image resolution in pixels You will be prompted for this when you close the file selection dialog box Saving Graphs You can save a graph complete with all its curves cursor settings and annotations to a binary file for later retrieval Note that all the graph data is stored not just that needed for the current view If a long run was needed to create the graph the file could be quite large Saving Select command shell menu File Graph Save As or graph menu File Save As to save a graph that has never been saved before To update a saved graph use command shell menu File Graph Save or graph menu File Save Restoring Select command shell menu File Graph Open or if a graph window already exists graph menu File Open Viewing DC Operating Point Results 260 Schematic Annotation You can annotate the schematic with the results of a DC operating point analysis This requires special markers to be placed on the schematic You can instruct SIMetrix to place markers at every node or you can place them manually To place a voltage marker manually use the schematic popup Bias Annotation Place Marker or use control M The text displaying the value will be placed on the sharp side of the marker which to start with points up If you are placing the marker on a vertical wire you might wish the text to be on one side T
413. used to modify the existing definitions You can disable the built in definitions from the options dialog box File Options General Menu Short cuts These are keys which activate defined menus The key name is displayed to the right of the menu text All menu definitions may have short cuts specified using the shortcut switch for the DefMenu command A potential problem arises if the same key is used for a short cut and a key definition using DefKey If this happens the DefKey definition takes precedence User Defined Toolbars and Buttons All toolbars and buttons are user definable and it is also possible to create new toolbars and buttons Full details are provided in the Script Reference Manual Chapter 7 350 Chapter 13 Sundry Topics Startup Script The startup script is executed automatically each time SIMetrix is launched By default it is called startup sxscr but this name can be changed with in the options dialog box File Options General The startup file may reside in the script directory defined by ScriptDir option variable or in a user script directory defined by UserScriptDir option variable The most common use for the startup script is to define custom menus and keys but any commands can be placed there To edit the startup script select the File Scripts Edit Startup menu item 351 User s Manual Index LIB 165 OUT file 261 PARAM 155 param 155 3dB points calculating 251 700Exten
414. usses with different names connected together One name has to win Next the netlist is read in by the simulator but the simulation is not started This will identify any devices for which models have not been found Schematic Preferences Component Toolbar The default toolbar show a selection of symbols useful for either CMOS IC design Micron versions or discrete circuit design all other versions There are however many more buttons available and these can be added as desired To do this select the schematic menu View Configure Toolbar This will display a dialog box allowing full customisation of the component buttons on the schematic toolbar Note that the toolbar configuration in SIMetrix mode is independent of the configuration in SIMPLIS mode Further customisation of all toolbars is possible using script commands You can also define your own toolbars and buttons Full details may be found in the Script Reference Manual Component Placement Options You can specify whether or not you prefer multiple or single placement of components By default placement of components from the schematic tool bar is repetitive while placement of components from the menus is done one at a time This can be changed Select the command shell menu File Options General In the schematic sheet the options available are presented in the Placement box Adding and Removing Worksheets A number of standard sizes of worksheet are included See me
415. ut mV 60 50 40 301 201 ifSt attempt 0 2 4 6 8 10 Time uSecs 2uSecs div As you can see The problem with the trailing edge has been fixed and the ringing is much improved Now let s have a look at the ringing in more detail To do this we need to zoom in the graph by adjusting the limits of the axes There are two ways of doing this The quickest is to simply drag the mouse over the region of interest The other method is to manually enter the limits using the Edit Axis Dialog Box To zoom with the mouse proceed as follows 1 2 36 Make sure that the graph window is selected by clicking in its title bar Place the cursor at the top left of the region of interest i e to the left of the y axis and above the top of the red curve Press the left mouse key and while holding it down drag the mouse to the bottom right of the area you wish to zoom in You should see a rectangle appear as you drag the mouse Release the mouse key You should see something like Chapter 2 Quick Start 601 501 With R added 40 301 Amplifier Output mV 201 0 50 100 150 200 250 300 350 400 Time nSecs 50nSecs div If you don t get it quite right press the Undo Zoom button to return to the previous view We can probably improve the ringing by adding a small phase lead in the feed back loop This can be done by connecting a small capacito
416. vely Moving Place cursor inside the box and drag to new location Editing Properties Double click on the box or select then menu Annotate Edit Selected Object A dialog like the one shown for legend boxes see above will be displayed Note when editing the label you can use the symbolic constants as detailed in Placing above Caption and Free Text The Caption and Free Text objects are essentially the same the only difference is their initial font size and position Placing Select menu Annotate Caption or Annotate Free Text Enter required text then Ok You can use the symbolic constants Yodate Y time and version to represent creation date creation time and the product version respectively Moving Place cursor inside the box and drag to new location 257 User s Manual Editing Properties Double click on the box or select then menu Annotate Edit Selected Object This will open a dialog similar to the one shown for curve markers but without the Automatic option for text alignment Copying to the Clipboard 258 Overview SIMetrix offers facilities to copy both graph data and the graph s graphical image to the system clipboard This provides the ability to export simulation results to other applications The data for example may be exported to a spreadsheet application for custom processing while the graphical image may be exported to a word processor for the preparation of documents SIMe
417. viable then a great deal of time will have been saved System Requirements Operating System Windows Requires Windows NT4 with service pack 6 or Windows 2000 or Windows XP or any later system 29 User s Manual At the time of preparing this manual Windows Vista had not been released SIMetrix has however been successfully tested on a late Beta version and full support for Windows Vista will be provided once it is released SIMetrix 5 will not install or run on Windows 95 98 or ME Linux Currently tested and supported distributions are Redhat 7 2 7 3 8 0 and 9 0 SuSE 8 0 8 1 8 2 and 9 0 See http www catena uk com for information on the latest supported distributions Hardware SIMetrix will run satisfactorily on any hardware that is sufficient to run the machine s operating system Recommended System If you regularly run large circuit simulations or long runs on smaller circuits we recommend investing in the most powerful CPU available A large RAM system can be useful as this will allow caching of simulation data This will speed up plotting results if a large amount of data is generated The data is stored to disk in an efficient manner and therefore substantial RAM is not essential unless the circuits being simulated are very large indeed 20 000 MOSFETs requires around 64MBytes A high performance bus mastering SCSI disk system will improve simulation performance a little Upgrade Notes 30 Upgrading
418. w Sub menu Select the location for your new menu then press Add Menu Enter the menu name as required The new sub menu will have one single empty item which you can select to add new items to the sub menu The empty item will not appear in SIMetrix menus To Edit or Add an Accelerator Key Select the menu item to which you wish to assign the accelerator key Press Accelerator You will now be asked to press a single key or key combination with shift control or alt The key you press will be assigned to the menu Press Remove to delete the accelerator key assignment To Reset to Factory Settings Press Reset to reset the menu system back to factory settings Usually this means that the menu system will revert to the structure defined when SIMetrix was first installed However if you defined any menus in the startup script using the DefMenu command these menus will be faithfully restored as well Reopen Menu The Reopen menu in the Command Shell File menu is dynamically updated to include schematic files recently opened or saved The items in this menu are not listed in the Menu Editor and cannot be edited The Reopen sub menu itself should not be deleted or moved to a new sub menu nor should it be renamed but it may be repositioned in the command shell s File menu as desired Message Window Chapter 10 The Command Shell The message window is the window in the command shell below the command line The ma
419. wever depend on the type of adapter card and display driver you are using Default OnStart Options Determines when dialog temporary simulation data is deleted Possible values Never OnStart OnClose and OnDelete See Graph Probe Data Analysis on page 327 for details Default SHAREPATH SymbolLibs default sxslb Name and location of default symbol library Chapter 13 Sundry Topics Name Type User interface support Description DevConfigFile Text DigAxisHeight Numeric DisplaySimProgressMessage Boolean EchoOn Boolean Editor Text ExportRawFormat Text GlobalCatalog Text unsupported Default SHAREPATH DeviceConfig cfg Name and location of device configuration file See Simulator Reference Manual for details Default 8 0mm Options Height of digital axis in mm dialog Screens are typically 75pixels inch Default False If true a message will be displayed in the command shell indicating the start and end of a simulation When set all commands are echoed to the command shell message window This is used primarily for script debugging Options dialog Default NOTEPAD EXE Default text editor Options dialog Default SPICE3 Possible values SPICE3 SPECTRE and OTHER Controls format of raw output See Exporting SPICE3 Raw Files on page 278 No Default SHAREPATH all Location and base name of global catalog file usually referred
420. while using the mouse to select the desired items in the usual way Selecting Wires Only Hold down shift key while performing select operation Holding Down the ALT Key while selecting will limit component selection to only devices that are wholly enclosed by the selection box Zoom Area Press a button on schematic Drag mouse to zoom in on selected area Zoom Full Fit to Area Select popup Zoom Full or press the HOME key to fit the whole schematic in the current window size Circuit Rules The following design rules must be observed for the simulation to run correctly Note that most circuits obey them anyway and they do not impose serious limitations on the capability of the simulator s There must always be at least one ground symbol on every circuit 7 Every node on the circuit must have a de path to ground If you do have a floating node connect a high value resistor e g 1G between it and ground There must not be any zero resistance loops constructed from voltage sources and or inductors If you do have such loops insert a low value resistor It is best to make the resistance as low as is needed to have a negligible effect on your circuit but no lower There should be at least two connections at every node Failure to observe the above usually leads to a Singular Matrix error 55 User s Manual Circuit Stimulus Most circuits require some form of input signal such as a pulse or sine wave
421. will refer to the most recent block that was used to descend into it The block that a schematic refers to is always displayed in the schematic s status bar as illustrated below EN C Program Files SIMetrix50 examples hierarchy fastamp sxcmp Selected Joe Eile Edit View Simulator Place Probe Probe AC Noise Hierarchy Monte Carlo SUC a MXC QQ 7 pert OROe KKE EL TDK tamp semp bandgap sxcmp bg_amp sxemp are eee EOR a VOUT oe ai i i Te NBFSI7 BFS17 H FEE T Sidi 3 a r ET D P JE ii i ya fee oe es BCSSER AUTR a EAR koU E mers Nprsi7 BFS17 VINN or gt Necesas Ni de aaa L100 zrn aa se LJ200 HRE p 4 ad Select x 0 83 yii Top level reference of block To plot a node in U2 ascend to parent TOP SCH in the above example then descend C Program Files SIMetrixS0 examples hierarchy top sxsch Pathname of root into U2 The same schematic as above will be displayed but will now refer to U2 instead of U1 Plotting Currents In the same way that you can plot currents into subcircuits in a single sheet design so you can also plot currents into hierarchical blocks at any level Plot Journals and Updating Curves Overview You can repeat previous plotting operations in one of two ways 234 Chapter 9 Graphs Probes and Data Analysis The Update Curves featur
422. wish to plot Press the left mouse button A graph of the voltage at that point will be created The new curve will be added to any existing graph if the X axis has the same units Otherwise a new graph sheet will be created Random Voltage Probing On New Graph Sheet Select the schematic menu item Probe Voltage New Graph Sheet Using the mouse place the cursor over the point on the circuit you wish to plot Press the left mouse button A graph of the voltage at that point will be created A new graph sheet will be created for it unconditionally Random Current Probing Select the schematic menu item Probe Current Using the mouse place the cursor at the device pin whose current you wish to plot Press the left mouse button A graph of the current at that point will be created The new curve will be added to any existing graph if the X axis has the same units Otherwise a new graph sheet will be created Random Current Probing On New Graph Sheet 1 Select the schematic menu item Probe Current in Device Pin New Graph Sheet Using the mouse place the cursor at the device pin whose current you wish to plot Press the left mouse button A graph of the current at that point will be created A new graph sheet will be created for it unconditionally Probing dB and Phase for AC Analysis In AC analysis you will probably want to plot signals in dB and you may also want to plot the phase of a signal 1 Selec
423. xis switch must be specified e g Curve AutoAxis L3 P Manually Creating Axes and Grids Two toolbar buttons Create new grid and Create new axis allow manual creation of new axes and grids These will be initially empty Subsequent random probe operations will use the new axis or grid unconditionally as long as it remains selected see below Selecting Axes Some operations are performed on the selected axis or grid The selected axis or grid will be displayed with its vertical axis line a deep black while the remaining axes and grids will be light grey Newly created axes and grids are always selected To select an axis click the left mouse button immediately to the left of the vertical axis line Moving Curves to Different Axis or Grid You can freely move curves around from one axis or grid to another Proceed as follows 1 Select the curve or curves you wish to move by checking its checkbox next to the coloured legend which designates the curve 2 Select the axis you wish to move it to See above 3 Press the Move selected curves to new axis button The curves will be re drawn on the new axis Any axes that become empty as a result of this operation will be deleted unless it is the Main axis See section below on Deleting Axes 237 User s Manual Deleting Axes To delete an axis select it then press Erase axis button Note that you cannot erase an axis or grid that has curves attached to it nor can you erase the M
424. xtension of the netlist format to tell the simulator what the pin names are Chapter 5 Components Chapter 5 Components Overview In this chapter we describe the components available at the schematic level Broadly speaking components fall into two categories namely numbered and generic Numbered components are devices that have a manufacturer s part number and are described by a model either supplied with SIMetrix or by the manufacturer itself Generic components are devices that are defined by one or more parameters that are entered by the user after the component has been placed on the schematic A transistor like a 2N2222 or BC547 is an example of a numbered component and a resistor is probably the simplest example of a generic component There are some components that have characteristics of both types CMOS IC designers would use MOSFETs defined by a model but will then customise it with length and width parameters Saturable inductors have an underlying model to describe the core s characteristics but a number of user defined parameters to define the geometry and air gap Numbered components need a model which is usually stored in the model library Refer to Device Library and Parts Management on page 157 for details This chapter is concerned only with devices at the schematic level Many of these devices are implemented directly by the simulator For example the simulator has a bipolar transistor model built in and such
425. xtension option variable 345 Graphs 212 annotation 254 258 AutoAxis 237 captions and free text 257 changing curve weight 328 changing digital axis height 328 copying to clipboard 258 creating new axes 237 356 Index creating new grids 237 cursors 242 247 see also Graph cursors deleting axes and grids 238 deleting curves 241 editing axes 238 hiding curves 241 highlighting curves 242 logarithmic 217 232 measurements 247 moving curves 237 multiple y axes 235 naming curves 241 plotting 212 printing options 327 saving and restoring 260 scrolling 253 selecting axes and grids 237 selecting curves 241 showing curves 241 zooming 253 GridPrintWidth option variable 336 Grids creating new 237 deleting 238 reordering 239 Group curves multi step analysis feature 195 Group delay plotting 219 GroupDelay function 303 GroupPersistence option variable 240 336 H Hamming FFT window 226 handle property 105 Hanning FFT window 226 HideSchematicGrid option variable 336 Hierarchical schematics see Schematic hierarchical HighlightIncrement option variable 336 HistoCurveStyle options variable 336 Histogram function 303 Histograms 265 HPBW function 273 357 User s Manual I if template property keyword 112 ifd template property keyword 113 Iff function 304 IIR function 304 im function 305 Impedance probing 220 Importing data 277 incscript property 105 Inductor editing values 137 initial condition 138
426. y SIMPLIS Conversely any lines following SIMULATOR SIMPLIS will only be accepted by SIMPLIS and will be ignored by SIMetrix All lines before any occurrence of SIMULATOR or after SIMULATOR DEFAULT will be accepted by both simulators Running the Simulator SIMetrix To run simulator select the Simulator Run menu item press F9 or select the run button in the Simulator Choose Analysis dialog box A dialog box will show the status of the simulation You can pause the simulation by selecting the Pause button on the simulator status dialog box To restart select the Resume button the Pause button changes name when simulation pauses or the Simulator Resume menu item There is no obligation to resume a simulation that has been paused If you start a new run after having paused the previous one you will be asked whether you wish to abandon the pending simulation run 65 User s Manual Notes 1 There is no need to specify in advance of the simulation what voltages currents and or powers you wish to look at By default everything except signals internal to some device models are stored in a disk file You can decide after the run is complete what you wish to look at 2 It is recommended that any schematics are saved before a run is commenced especially if the run is expected to take a long time SIMPLIS If the schematic is in SIMPLIS mode the procedure described above will start the SIMPLIS simulator A window showing the pro
427. ymbol that are already placed will not change You can use the popup menu Restore Properties to restore properties to their symbol defined values For more information see Restoring Properties on page 106 If you wish a property value to always follow the definition in the symbol then you must protect it See Defining Properties on page 97 for details Summary of Simulator Devices The following information is needed to define schematic symbols for the various devices supported by the simulator In order to be able to cross probe pin currents the pin names for the schematic symbol must match up with those used by the simulator So for a BJT bipolar junction transistor the simulator refers to the four pins as b c e and s for base collector emitter and substrate The same letters must also be used for the pin names for any schematic BJT symbol The simulator device pin names are listed below The model property is the schematic symbol property which describes what type of device the symbol refers to SPICE uses the first letter of the component reference to identify the type of device The SIMetrix netlist generator prefixes the model property and a symbol to the component reference to comply with this This makes it possible to use any component reference on the schematic Device Model Pin no Pin Pin function property names XSPICE device A Arbitrary Sources B 1 p 2 n Bipolar junctio

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