nanoZ User Manual (TDT) - Tucker
Contents
1. argN The function name is not case sensitive and can be one of the following Name Purpose getversion Returns the version of the nanoz ME file enumdevs Enumerates attached nanoZ devices open Opens a free nanoZ device for access by other functions close Closes an opened nanoZ device releases system resources selectchannel Selects a channel setfreq Sets the test frequency for impedance measurements startimpmetering Starts impedance measurement getimpdata Retrieves impedance measurement data getwaveformcaps Returns information about the waveform generation capabilities getplatingcaps Returns information about the electroplating capabilities 17 nanoZ User Manual preparewaveform Prepares a waveform for use during electroplating startplating Starts electroplating setplatingdata Retrieves electroplating voltage feedback data stop Stops impedance metering or electroplating Sample scripts The following demonstration Matlab scripts are provided o get info m display hardware information about all attached nanoZ devices measure impedance m measure the impedance of a single electrode o electroplating m electroplating with a DC constant current They can be found in the Matlab SDK folder accessible from the short cut in the Windows Start Menu These sample scripts along with the supporting functions they use should provide a foundation for building you own customized nanoZ applications 18 Function descriptions getver2. ASCII file format Requires Matlab 2006a or later The figures below show the percent error in A impedance magnitude and B phase measurements as a function of impedance magnitude and test frequency across the working range of the nanoZ A B 20 20 15 BEE D D 2 VE ee a EE DEE Z MOhm 10 ich S NN 1000 1500 2000 frequency Hz 0 500 1000 1500 2000 500 frequency Hz The same data on a semi log plot ss ss ss db bs web e eee es Pe er ee mm e e e e e Z MOhm Z MOhm gt 2 ran 1500 2000 0 500 1000 1500 2000 frequency Hz 0 500 1000 frequency Hz 29 nanoZ User Manual Appendix C Channel Mapping The nanoZ application stores adaptor and electrode site mappings in the electrodes ini file which can be accessed from the link in the Windows Start menu You can use a standard text editor to add remove or modify the existing channel mappings however care must be taken to adhere to the correct syntax described in this Appendix We recommend you backup electrodes ini before making any changes to this file Adaptor definitions The mapping between the nanoZ s internal 64 channel MUX and the two native Samtec connectors is depicted here as viewed facing the connector with the lowest channel numbers closest to the USB port end of the nanoZ Use this numbering scheme when programming the channel selection in the Matlab SDK or when d
3. in Hz 20 Return values freq achieved The frequency in Hz which can be generated by the device as close as possible to the desired frequency and on which the actual measurement will be performed fs optional return value It receives the sampling frequency used for signal measurement Remarks This function prepares the device for impedance measurement During measurements the nanoZ applies a sinusoidal current on the target electrode and records the voltage across at the sampling frequency returned by the fs output argument startimpmetering Starts impedance measurement Usage nanoz startimpmetering handle nsam measure numdsps Arguments handle handle to an opened device returned by the open function nsam measure number of samples to measure per single impedance reading numdsps number of overlapping impedance measurements Return values none Remarks Calling this function initiates the impedance measurement process applying sinusoidal test current to the target electrode and measuring the voltage across it After a given number of samples is collected which is specified by the nsam measure argument the data are converted to a single average impedance reading Because it may take considerable time typically about a second to collect data for result conversion it is possible to perform multiple concurrent conversions partially overlapping in time with each other This allows more impe
4. means that channel 4 of the adaptor is connected to site 15 Since the mapping is determined by ordinal position n is only used for the site label in the Probe window and Probe report and can therefore use any numbering scheme This added flexibility allows for zero based vs one based electrode site numbering different data acquisition systems use one or the other or for example the row and column site numbering used by the MCS 8x8 standard MEA Finally restart the application or click File Reload definitions from the Main Menu to make the nanoZ application aware of any changes to electrodes ini 32 Appendix D NZ CAL Component Values The following table shows the channel mapping for the bank of test resistors 1 tolerance and capacitors 5 tolerance on the NZ CAL adaptor channel R MOhm C nF channel R MOhm C nF 1 6 8 17 short circuit 2 10 0 1 18 0 12 p 3 4 7 19 1 0 A 3 3 20 1 0 S 5 20 21 0 0051 6 2 2 22 0 51 7 1 0 23 0 010 S 8 1 5 24 1 0 9 10 25 100 10 1 0 26 S 10 11 1 0 27 1 0 12 0 82 28 0 22 13 8 2 29 0 033 14 1 0 gt 30 0 020 15 13 3 31 1 0 16 open circuit 32 0 051 R and C in parallel The measured phase angle of pure resistors should be 0 with an impedance that is independent of test frequency whereas pure capacitors should report a phase angle of 90 with an impedance magnitude that varies inversely with frequency For comparison
5. nanoZ_firmware1 13x hex 4 Select the nanoZ device you wish to update by serial number If only one device is plugged in only one serial number will appear in the drop down list 5 Click Update While the new firmware is being uploaded the green LED on the nanoZ will flicker Do not unplug the nanoZ during the upload The message 3 nanoZ User Manual Firmware updated successfully indicates when the process is complete You can now click Exit and continue using the nanoZ application 6 If the update is interrupted or cancelled the nanoZ will not function properly Repeat these instructions to upload the firmware completely Probe adaptors Probes or electrode arrays that have Samtec connectors MOLC 110 01 S Q can be plugged directly into the nanoZ assuming they conform to the nanoZ s native pin mapping see Appendix C The nanoZ comes with a NZA DIP16 adaptor for probes that use a DIP16 connector and a variety of other adaptors are available for commonly used interconnects such as those from Millmax and Omnetics All NZA series adaptors should be plugged into nanoZ so that the 3 pin header on the adaptor is closest to the USB port end of the nanoZ If using the NZA DIP16 adaptor mapping defined in electrodes ini be sure to plug the adaptor into the lower Samtec socket closest to the edge of the nanoZ In the current version of the nanoZ only R1 is connected to the internal circuitry R2 and R3 are
6. 05 0 006 0 4 00 00 05 0 006 3 0 00 00 05 0 051 0 3 00 00 05 0 052 0 5 00 00 05 0 120 0 0 00 00 05 0 052 0 2 00 00 05 The upper panel of the report shows information about the currently selected I m SE probe and when it was most recently z 0 518 0 1 00 00 05 0 515 0 0 00 00 05 To view or hide the report window select View Report from the Main Menu on oot GO PA rz Val 00 00 05 tested user defined criteria for flagging Ui 7 whether or not an electrode site is faulty is oss ss 00 00 05 and several display options e If an electrode has been selected in the main nanoZ program the probe name and description extracted from the corresponding electrodes ini file is shown The time and date when the last impedance test or plating procedure began is also displayed The Short and Open user input boxes are editable An electrode is considered shorted when the measured impedance magnitude falls below the value entered in Short and is considered open circuit when the impedance magnitude is greater than the value entered in Open Impedances within this range are considered normal The left most column in the spreadsheet displays the electrode site index The column titles show the impedance test frequency and if applicable the plating current that was applied In electrode impedance spectroscopy mode there will be additional columns two for each test frequency The body of the spreadsheet contains the most re
7. Note that if the initial electrode impedance measurement is already less than or equal to the target impedance no current will be applied to that electrode D Click the Autoplate button to begin the electroplating sequence Clicking on Autoplate again or pressing ESC at any time will pause the plating and you will be given the option of skipping the current electrode Ignore continuing the sequence or stopping The pre and post plating impedance test results in the Probe report can be saved by clicking the kd icon Impedance spectroscopy mode This mode cycles through all or a subset of electrodes on the selected probe measuring the impedance of each electrode at multiple test frequencies No adaptor Omm Probe not selected _ Scope CH1 SH est Impedances Giz V Trig BD DC E tronlate dei v Z f Spectroscopy gt Test cycles A7 AHC Test probe j Aves Frequencies A Select the impedance Test Frequencies in Hz from the check box list or check All to test at all frequencies in the list Click the lA icon to edit the list of test frequencies Valid frequencies range between 1Hz and 4986Hz The nanoZ will generate test sinusoidal waveforms as close as possible to the specified test frequencies The exact test frequencies used will be displayed in the status bar and in the column titles of the Probe report B Choose the number of Test cycles The default setting of 40 cycles is a good trade
8. activation time 4 97914 tg 2 028 dase Gebees O Match charge capacity 7 v Va s7 Manual control 1 bi Hz Duty oe e Fr 5 S Ta NW gd Duration 30 s A e Activate probe A Only the Fixed activation time is implemented in the current software version so this setting is currently ignored B Set the Activating current Both current settings can be adjusted from 12uA electrode negative to 12uA electrode positive in 100nA steps by moving the position of the sliders The exact currents that will be applied to the electrode are indicated above the sliders The DMM has limited measurement resolution 89mV and should be considered approximate however the calibrated current readings adjacent to the sliders are accurate to within a few nA nanoZ User Manual C Set the desired activation frequency the Duty cycle and the activation Duration per electrode The Duty cycle determines the relative time of the two current phases where the percentage refers to the first current setting in B If Test Z is checked the post plating electrode impedance is measured at the test frequency specified D Click the Activate probe button to begin the activation sequence To illustrate a typical activation sequence using the settings shown above as an example i e 1Hz activation frequency 25 duty cycle currents 5uA to 2uA and duration 30s the nanoZ will apply 30 activation Square wave cycles comprising a 5uA electrode
9. at the expense of a longer testing duration whereas decreasing the number of cycles may lower accuracy due to insufficient localization of the test signal in the frequency domain The testing time per site is displayed in the status bar C Click the Test probe button to begin the test Clicking on Test probe again or pressing ESC at any time will pause the test and you will be given the option of continuing the test or stopping Impedance test results in the Probe report can be saved by clicking the kd icon DC electroplate mode This mode cycles through all or a subset of the electrodes on the selected probe applying a controlled DC constant current to each site It has two sub modes of operation fixed plating time per channel and match impedances mode whereby the nanoZ will only advance to the next channel when the electrode site impedance is lowered to the specified Target impedance The DC Electroplate mode has many possible applications including o plating with gold or other metals to lower electrode site impedances o deposition of conductive polymers such as PEDOT to simultaneously lower the electrode site impedance and improve the site charge capacity o electrode site cleaning o in vivo or in vitro rejuvenation of electrode sites o tissue lesioning and electrode track marking No adaptor Gi Dm Probe not selected C Scope CH1 SH est Impedar GES V Trig Fa DC Electroplate lt gt v Z f d A
10. electroplating but is not guaranteed to do so 26 Appendix A Principle of Operation For measuring impedance the nanoZ utilizes a voltage divider circuit According to Ohm s law the ratio of voltages V1 and V2 in the circuit is Vi Rep V2 Z This formula generalizes to AC sinusoidal signals where V1 V2 and Z are complex numbers whose angles represent phase relations in the circuit When a known voltage V is applied and V2 is measured it is possible to solve the above equation for Z which is exactly how the nanoZ measures impedance During impedance measurement test currents flow through the circuit The nanoZ uses a 4mV peak to peak sinusoidal waveform for V1 which yields a maximum test current through Z of 1 4nA RMS when Z is approaching zero and 0 7nA RMS when Z is 1MOhm The nanoZ has a single measurement circuit including the generator voltage V1 the amplifier for V2 and the reference resistor R e Different channels having different electrode impedances Z are connected to this circuit via an on board 64 to 1 analog multiplexer Here is a simplified schematic of the overall circuit Measurement circuit Attenuator Amy p p Sinusoid Magnitude and Phase detector Constant current source SW Either the impedance measurement circuit or the electroplating constant current source can be connected to a channel via switches SW1 and SW2 The electroplating current sour
11. must close the device after they have finished using it to release system resources and allow other programs access If a program fails to close the device it will stay open until Matlab finishes or until the nanoz MEX file is unloaded To unload the MEX file issue the Matlab command clear nanoz which will unload the MEX file closing all open nanoZ devices selectchannel Selects a channel to perform impedance measurement or electroplating on Usage nanoz selectchannel handle channel Arguments handle handle of an opened device returned by the open function channel channel number to select from 1 to 64 or O to de select all channels Return values none Remarks This function connects the measurement circuit to a specific channel Prior to switching channels any impedance measurement or electroplating that was in progress is automatically stopped Channel switching may cause a transition on the measurement circuit that lasts about 0 5 seconds To preserve accuracy impedance measurement is not recommended during this period After switching channels the circuit is put into passive mode not applying any voltage or current to the target electrode setfreq Sets the test frequency used for impedance measurement Usage freq achieved fs nanoz setfreq handle freq desired Arguments handle handle to an opened device returned by the open function freq desired The desired test frequency
12. off between accuracy and speed Increasing the number of cycles will marginally improve the accuracy due to averaging at the expense of a longer testing duration whereas decreasing the number of cycles may lower accuracy 14 due to insufficient localization of the test signal in the frequency domain The total testing time per site is displayed in the status bar C Click the Test probe button to begin the test Clicking on Test probe again or pressing ESC at any time will pause the test and you will be given the option of continuing the test or stopping The impedance spectroscopy results in the Probe report can be saved by clicking the kd icon Activation mode This mode uses cyclic voltammetry to increase the charge capacity of all or a subset of electrodes on the selected probe for either a fixed duration or to match a target electrode charge capacity Activation mode applies a bipolar constant current square wave to the electrode which both lowers the impedance and increases the charge capacity two properties that are desirable for effective electrical stimulation With suitable electrodes and appropriate waveform settings the activation mode can also be used for in vivo or in vitro microstimulation T nanoZ File Edit Device Mode View Help No adaptor v DMM Probe not selected v C Scope CH1 OP Impedances CH2 Trig QB DC Electroplate lt gt d ZC SES Mode A Activating current RE Fixed
13. reserved for future expansion If you wish to make your own reference electrode cable be sure that it connects to R1 Calibration adaptor The nanoZ comes supplied with a 32 channel calibration adaptor NZ CAL comprising a bank of resistors and capacitors of various impedances Appendix D Use this adaptor to confirm the accuracy of your nanoZ across the specified working range Appendix B The nanoZ does not require routine calibrations however future firmware and software upgrades may necessitate a device re calibration for example to extend the nanoZ s functionality accuracy or working range The NZ CAL 4 adaptor may also be used to test whether 3 party electrode adaptors or tether cables introduce errors in the impedance measurements nanoZ User Manual nanoZ Software Overview There are two options for interfacing with the nanoZ a Windows based nanoZ application and the Matlab SDK which runs under Matlab Refer to the Matlab software development kit section of the User Manual for detailed instructions on how to control the nanoZ from Matlab The nanoZ application can be run from the Windows Start menu or Desktop shortcut The application will connect with the first available nanoZ device If the nanoZ is plugged into the USB port after the application has already started it can be selected from the Device list on the Main Menu adaptor SW electrode e X a e robe not selected d Scope F ion bri
14. volts Remarks During electroplating the nanoZ monitors the voltage on the target channel This voltage is sampled at the frequency that is returned by the getwaveformcaps function This function returns all samples that have been collected since electroplating was started or from the time this function was previously called It may be an empty matrix if no new values were acquired The user application should call this function every 30ms or a data overrun may result The total number of samples returned by this function since electroplating was started can be used to determine the exact electroplating duration 25 nanoZ User Manual Values returned by this function take into account device calibration and have units of volts stop Stops impedance metering or electroplating Usage nanoz stop handle Arguments handle handle to an opened device returned by the open function Return value none Remarks This function stops any impedance measurement or electroplating process The measurement circuit remains connected to the selected channel Consequently a new impedance measurement on the same channel may start immediately because there will not be any transient channel switching artifact The Matlab application should call this function prior to calling any function other than getimpdata or getplatingdata on the target device Calling other nanoZ library functions may also indirectly stop impedance measurement or
15. Sonera eee erence er eer eee eee 15 Matlab Software Development Kit ccscsccsssccsceccececcscsccccsccccsccccsceccscescsceccscscesens 17 t e E 17 VS UU 6 k 6 gl 6 Hope ne eee een oer acre e ene reese een emer eee ee eee eee 18 FUG ULM Cle SCF 10 ee 19 EE 19 EE 19 DEE 19 te 20 EE 20 EE 20 EE 21 GEP O ee 21 Eege 22 EEN EE 23 TO COW OC ege 24 tee a 6 005109 E 24 EE 25 EE 26 Appendix A Principle Of Operation cccscscsscsccsceccccsccccsccccsceccccsscscescccnccccececcsceees 27 Appendix B Technical Specifications csscscscscsscsceccccccscsccccececsccccccscscsccccscsseseces 28 ER 28 OI rcs cape pets tec ccst pases ct coerce I TA A EE AIA O E A 28 Appendix C Channel ET Te UE 30 Adaptor COTTA VON e E 30 Electrode COTM I CIO e EEN 31 Appendix D NZ CAL Component Values 2 Year Limited Warranty sscsssseees Welcome to the nanoZ The nanoZ was specifically designed for multichannel electrode arrays It has inbuilt testing modes for measuring electrode site impedances and electrode impedance spectroscopy EIS in addition to several electroplating modes for automated site impedance matching site activation and site cleaning The setup and operation of the nanoZ is described in this user manual and includes information about the Matlab Software Development Kit SDK for developing your own customized nanoZ applications What s in the box Each nanoZ comes supplied with nano
16. Z device 1 8m USB cable NZA DIP16 adaptor NZ CAL test adaptor 3 pin to alligator clip cable Installation CD 4 stick on feet optional CO O E O 2 nanoZ User Manual If any item is missing or appears to be damaged or faulty please contact the distributor from whom you purchased your nanoZ Software installation 1 Connect your nanoZ to the computer using the USB cable provided Let Windows search for the driver on the installation CD in the Drivers subfolder Follow the on screen instructions to install the USB drivers Note that Windows 7 may have inbuilt FTDI drivers which are fine to use instead 2 Run setup exe from the installation CD Follow the on screen instructions to install the application suite including the optional Matlab SDK if you want to develop your own nanoZ applications under Matlab 3 The software is ready for use You can run the nanoZ control program from the Windows Start Menu or Desktop Shortcut Note that if you are re installing the software using the setup exe installer it will overwrite any existing electrodes ini and prefs ini files without warning If you have modified these files be sure to back them up before doing a re installation Setting up the nanoZ The nanoZ requires no additional hardware other than a PC with a USB port A simple way to mount the nanoZ is with a regular laboratory retort stand or tripod and a three prong clamp Position the nanoZ ove
17. ce is programmed by a voltage coming from an 8 bit DAC yielding 256 current steps between 12uA electrode negative and 12uA electrode positive The DAC can produce both DC and alternating waveforms from the nanoZ s on board memory E nanoZ User Manual Appendix B Technical Specifications Hardware Number of channels Z measurement range Z accuracy amp precision Z test current Test signals Electroplate mode Electroplate range Electroplate resolution LED Indicators EEPROM PC interface Connectivity Weight Dimensions 64 1kQ to 10MQ 1kQ display resolution 5kQ to 5MQ 5 channels matched to within 1 1 4nA RMS max bias leakage current 50pA typ default 1kKHz sinusoid waveform frequency range 1Hz to 4986Hz arbitrary user defined waveforms Bipolar constant current 12uA 4 9 4 3V compliance 100nA adjustment step nom power operating mode device specific calibration values USB 1 1 or 2 0 no additional power supply required Two Samtec FOLC 110 01 S Q 2 5mm phono socket future I O optional electrode adaptors 2 9 oz 82 g 3 2 X 2 8 x 0 47 inches 81 x 70 x 12 mm The nanoZ electrode adaptors and all accessories are certified ROHS Compliant Software Operating systems Operating modes Data export Matlab SDK included 28 Windows XP XP64 Vista or 7 Probe impedance test electrode impedance spectroscopy DC electroplate site activation manual operation
18. cent site impedance measurements for all tested sites If the Phase checkbox is checked then both the impedance magnitude and phase are displayed If unchecked only the impedance magnitude is shown For electroplating modes the cumulative plating time is shown for each individual electrode which may vary from site to site for example if impedance matching mode was run Both pre and post plating impedances are stored in separate columns to the left and right of the cumulative plating time respectively If the Statistics checkbox is checked then the average impedance magnitude and phase standard deviation of all tested sites is shown at the bottom of each column Note that if the Condition checkbox is checked only normal sites are included in these aggregate statistics nanoZ User Manual If the Condition checkbox is checked then shorted site impedance values are highlighted in red on the spreadsheet and Probe layout window Open sites are highlighted in blue Normal sites are displayed in green The report can be saved to file by clicking the kl icon in the main program window or selecting File Save Report from the Main Menu Data are saved in tab delimited ASCII format according to the current checkbox settings i e phase information will be exported only if the Phase checkbox is checked aggregate Statistics are exported according to the Statistics checkbox etc Operating Modes The nanoZ application has five separate m
19. dance readings per second The multiplication factor is specified as the numdsps parameter For example if one measurement lasts one second and numdsps parameter is set to 4 there will be 4 impedance readings per second While measuring impedance the user program has to poll the results by calling the getimpdata function every 30ms or a data buffer overrun may occur Prior to measuring impedance a channel must be selected and a working frequency must be specified by calling the selectchannel and setfreq functions respectively getimpdata Retrieves impedance measurement data 21 nanoZ User Manual Usage signal samples Z nanoz getimpdata handle Arguments handle handle to an opened device returned by the open function Return values signal samples vector of integers which are raw analog signal readings from the target electrode The user application may use these readings in order to monitor for example the noise and interference levels during impedance measurement If the signal is not clean the impedance reading may be inaccurate Z vector of complex impedance readings in Ohms Remarks During impedance measurement the user program must call this function approximately every 30ms to poll for incoming data Output vectors are sized according to the amount of new data that were collected between two successive calls of this function If no data were acquired the vectors will be empty In typica
20. der C The current can be adjusted from 12uA electrode negative to 12uA electrode positive in 100nA steps by moving the position of the slider with the mouse or arrow keys The voltage across the electrode site will be displayed on the DMM The DMM has limited measurement resolution 39mV and should be considered approximate however the calibrated current reading adjacent to the slider is accurate to within a few nA The DMM also indicates if the voltage is out 11 nanoZ User Manual of compliance that is if the voltage needed to achieve the desired current is greater than the nanoZ can generate To stop applying the current select Off A Impedance test mode This mode rapidly cycles through all or a subset of the channels on the selected probe measuring the impedance of each electrode The impedance results are tabulated in the Report window View Report No adaptor y Gi DRM Probe not selected v C Scope CH1 ew Test Impedances Chie Trig lt gt b d hus Activate sites Test frequency 1000 G Hz Test cycles 40 Ded Crest probe 1004Hz 00 01 16 per channel A Set the impedance Test frequency to the desired value The actual test frequency that will be used is shown in the status bar B Choose the number of Test cycles The default setting of 40 cycles is a good trade off between accuracy and speed Increasing the number of cycles will marginally improve the accuracy due to averaging
21. e ke H selectlo virtual DMM OH ie Impedances j aH K scope display kt E dp E DOUD mode selection e Activate sites Test frequency 1000 Hz Test cycles 40 17 d e settings for Current mode ki ffe prp fr pr fie fir Dr fie fir Dr fie Er Dr fie Er Dr fie Er Dr fie ir fr fie fr E dheseeeeee eeg ee e ee e ee ee ee ee e Re ee eee Di 1004Hz 00 01 16 per channel device status An intuitive graphical user interface makes the nanoZ easy to use User programmable electrode site configurations see Probe window provide a meaningful way to visualize the integrity of the electrode array and allow subsets of channels to be tested and or conditioned by selecting the relevant sites with a few mouse clicks A virtual digital multimeter DMM displays real time impedance measurements and the current plating voltage depending on the mode of operation Clicking on Scope or selecting View Scope from the Main Menu will display a virtual oscilloscope display with the test or plating output waveform in green and the measured input waveform in cyan Use the arrow icons to change the horizontal time and vertical amplitude zoom To switch back to the DMM display click DMM or select View DMM from the Main Menu The status bar displays information about the nanoZ device hardware The LED icon on the left hand corner of the status bar reflects the mod
22. e the first line in the NZA DIP16 definition MUX 51 75 375 means that channel 1 of the adaptor is connected to MUX channel 51 and is situated on the bottom left hand corner of the DIP 16 socket Finally restart the application or click File Reload definitions from the Main Menu to make the nanoZ application aware of any changes to electrodes ini Electrode definitions The format for the electrode definitions in electrodes ini is similar to that used for adaptor definitions Steps 1 to 4 for defining the electrode name description site appearance and outline are almost identical except for subtle differences in the field names Step 5 is different 5 the last section of the electrode definition is the most important as it defines the mapping from the adaptor pinout to the electrode site layout The NumSites field specifies the number of electrode sites The format for this mapping is Site n x y sizeX sizeY where n is site number x and y define the site location on the Probe window and sizeX and sizeY are optional values that replace the default dimensions in SiteSizeX and SiteSizeY thereby allowing for electrode arrays with different site sizes For simplicity specify all these values in microns The ordinal position defines the mapping between the electrode site and the adaptor pin number So for example the 4 line in the MCS 8x8 standard electrode definition 31 nanoZ User Manual Site 15 350 450
23. e LED on the actual nanoZ device and indicates the currently selected mode of operation off for passive mode glowing green for impedance mode and glowing red for electroplating mode Impedance data are displayed in an Excel like spreadsheet See Report window which can be saved to file for storage or further analysis in programs like Microsoft Excel or Matlab The specific settings for the manual and automated modes of operation are described in the next chapter of the User Manual Channel mapping To support the various electrode adaptors that are available for the nanoZ the nanoZ application seamlessly translates the probe site layout to the adaptor pin mapping and from the adaptor pins to the nanoZ s internal multiplexer MUX By mapping in two stages rather than directly from the probe layout to the nanoZ it is unnecessary to construct a new probe mapping for different adaptors probe site layout adaptor pin nanoZ MUX mapping channel Both adaptor mappings and electrode site layouts are defined in electrodes ini Refer to Appendix C for information on how to configure additional probe layout and adaptor mappings Adaptor window Adaptors can be selected from the drop down list of known adaptors i e those defined in electrodes ini located in the left top corner of the nanoZ main application window Select View Adaptor from the Main Menu to display a window depicting the adaptor If no adaptor is attac
24. e Plating current B WE Fixed plating time 0 012u4 SE is Match impedances SECH Menus cont a 1000 aji Tesz OO nc ie s Abt Davitopiate A Select the plating mode either Fixed plating time or Match impedances B Set the DC plating current The current can be adjusted from 12uA electrode negative to 12uA electrode positive in 100nA steps by moving the position of the slider The exact current that will be applied to the electrode is indicated adjacent to the slider The DMM has limited measurement resolution 89mV and should be considered approximate however the calibrated current reading adjacent to the slider is accurate to within a few nA C For a fixed plating duration per site set the desired plating Duration If Test Z is checked the post plating electrode impedance is measured For impedance matching mode set the desired Target impedance test frequency and plating Interval The plating interval specifies how long to apply the plating current before re testing the electrode impedance For example a setting of 2 will apply the specified current for two seconds test the impedance and alternate between these two modes every two seconds until the target impedance is achieved The 13 nanoZ User Manual total plating time is limited by the Retries setting Once this number of plating Z test cycles has occurred the nanoZ will advance to the next channel even if the target impedance has not been reached
25. esigning custom made electrode adaptors The electrode reference pins R1 R2 and R3 shown in red cannot be selected by the nanoZ software however R1 must be physically connected to the electrolyte in order to complete the circuit R2 and R3 are not currently used but are reserved for future versions of the nanoZ To describe the format of the adaptor definitions contained in electrodes ini the NZA DIP16 adaptor mapping is used as an example in the following step by step instructions 1 choose a name for the adaptor and enter it on a new line in the Known Adaptors section Spaces are allowed but the last character must have an sign to be recognized For the DIP16 adaptor the entry is NZA DIP16 2 create a corresponding section name for this adaptor by adding the adaptor name to a new line enclosed in square brackets e g NZA DIP16 3 the next few lines define the adaptor name description adaptor pin dimensions and whether the pins are round or square The values assigned to the Name and Description fields will appear in the drop down list of known adaptors and in the Report window respectively They should be succinct yet informative and include version identifiers if multiple versions of the same adaptor exist The ContactSizeX and ContactSizeY determine the relative size of the pins in the Adaptor window If RoundContact is zero the pins will be square otherwise they will appear round 30 4 the
26. g of the analog signal on the electrode is a fraction of the generator sampling frequency in this case 1 4 which also may be changed in the future The user program should rely on the fs adc parameter of the caps structure Waveforms must be uploaded into the memory of the nanoZ s microcontroller The current version has memory for waveforms up to 126 samples bytes long The minimum frequency that can be generated with a sampling frequency of 83333HzZ and 126 samples is approximately 661Hz Waveform interpolation is used to generate lower frequencies The interpol field of the caps structure lists supported interpolation factors Linear interpolation is used for factors of 8 or less 16x and higher interpolation is performed by 8x linear interpolation combined with 2x or higher ratio hold interpolation which effectively reduces the generator sample rate Using the maximum 1024x interpolation factor 8x linear 128x hold frequencies down to 0 645Hz can be generated For impedance measurement the MEX library automatically chooses the best interpolation factor and synthesizes a waveform of appropriate length to achieve a test signal frequency as close as possible to that specified by the user For electroplating arbitrary user supplied waveforms may be used which puts the responsibility of choosing waveform length and interpolation factor on the user application eetplatingcaps Returns information about electroplating capabilities Usa
27. ge caps nanoz getplatingcaps handle Arguments handle handle to an opened device returned by the open function Return value caps a Matlab structure with the following fields min current The minimum negative current in amperes which the nanoZ s electroplating current source can generate max current The maximum positive current in amperes which the nanoZ s electroplating current source can generate current step The minimum step size in amperes by which the requested electroplating current can be decreased or increased min voltage The minimum negative voltage which can be produced by nanoZ to maintain the requested current i e negative voltage compliance 23 nanoZ User Manual max voltage The maximum positive voltage which can be produced by nanoZ to maintain the requested current i e positive voltage compliance Remarks The values returned by this function reflect the device s calibration status not just the design specifications and can therefore vary slightly from device to device preparewaveform Prepares a waveform for electroplating Usage output waveform achieved current nanoz preparewaveform handle desired waveform Arguments handle handle to an opened device returned by the open function waveform user supplied waveform to be generated during electroplating Units are amperes Return values raw waveform device specific raw waveform which
28. he target electrode is constantly monitored To prevent a possible buffer overrun the user application must call the getplatingdata function to fetch the results of this monitoring The exact moment when electroplating actually starts is not predictable Depending on the waveform length uploading the waveform may take some time and delay the start of electroplating When the electroplating duration must be exactly controlled the application should determine the exposure time from the number of samples returned by the getplatingdata function and stop plating when the prescribed number of samples has been acquired lf for whatever reason the user application crashes during electroplating the nanoZ device will not be informed of it and will continue to supply electroplating current to the target electrode For this reason it is a good idea to encapsulate electroplating sections of the Matlab code in try catch clauses in order to ensure that electroplating is stopped in all cases even if an error occurs The most reliable way to stop electroplating without generating further errors is to execute a clear nanoz Matlab statement getplatingdata Retrieves electroplating voltage feedback data Usage voltage nanoz getplatingdata handle Arguments handle handle to an opened device returned by the open function Return value voltage a vector of voltage values measured across the target electrode during electroplating Units are in
29. hed to the nanoZ selecting No Adaptor from the drop down list of adaptors will show the layout of the 64 channels used by the native connector When a channel is active the corresponding pin on the Adaptor window is highlighted In passive or impedance testing mode the pin is highlighted in green in electroplating mode the pin is highlighted in red Channels that are not used not connected for a given adaptor as defined in electrodes ini cannot be selected regardless of operating mode For example the NZA DIP16 adaptor uses 16 of the 64 available channels and accordingly nanoZ User Manual only these 16 channels can be selected To re enable all 64 channels select No Adaptor Probe window The nanoZ application supports arbitrary probe site configurations and once defined in electrodes ini handles the channel mapping transparently Several example probes are provided with the default installation Probe definitions can be modified and new definitions can be added refer to Appendix C for a detailed description on how to do this Select View Probe from the Main Menu to display a window showing the probe electrode site layout with numbered sites When a channel is active the corresponding electrode site on the Probe window is highlighted As with the Adaptor window in passive or impedance testing mode the site is highlighted in green in electroplating mode the site is highlighted in red The probe layout wi
30. is produced on the basis of user supplied waveform taking into account device calibration achieved current values of electroplating current in amperes which are based on the raw_waveform values returned by this function Remarks This function converts the user specified electroplating currents into raw values that are output by the nanoZ s 8 bit DAC during waveform generation An attempt is made to produce a current waveform that is as close as possible to that requested taking into account the device calibration The application can modify the raw waveform prior to uploading it into nanoZ for example to implement dithering a technique which in some cases can overcome inaccuracies due to the 8 bit DAC quantization As there is a low pass filter after the waveform generation DAC fast changes in electroplating current will be dampened startplating Starts electroplating Usage nanoz startplating handle raw waveform interpol Arguments handle handle to an opened device returned by the open function raw_ waveform waveform of electroplating current to be generated in device specific units which can be obtained from the preparewaveform function 24 interpol interpolation factor to be used during waveform generation Return value none Remarks This function uploads the user specified waveform into the nanoZ s memory and starts the electroplating process During electroplating the voltage across t
31. l situations the Z vector is empty most of the time but occasionally it has one element the impedance reading that was most recently acquired Failure to call this function at regular intervals may result in a buffer overrun error Recovery from a buffer overrun requires impedance measurement to be stopped This will cause any pending results to be lost Note that if a buffer overrun error does occur the impedance measurement test waveform is still applied to the currently selected channel until the stop function is called setwaveformcaps Returns information about waveform generation capabilities Usage caps nanoz getwaveformcaps handle Arguments handle handle to an opened device returned by the open function Return value caps a Matlab structure with the following fields fs gen generator sampling frequency in Hz Typical value is 83333Hz fs adc Sampling frequency of the A D converter Typical value is 10417Hz maxsam Maximum length of the waveform in samples interpol List of Supported interpolation factors Remarks The nanoZ generates waveforms for impedance measurement and electroplating with an 8 bit digital to analog converter clocked at a sampling frequency of 83333Hz Since this may change in future firmware upgrades user 22 applications should not rely on the values quoted in the specifications but rather query the attached device for its actual capabilities fs gen parameter Samplin
32. most electrophysiology electrodes will have a phase angle between 50 and 80 indicating a largely capacitive impedance 33 nanoZ User Manual 2 Year Limited Warranty White Matter LLC White Matter the manufacturer of the nanoZ warrants to the Original purchaser that the nanoZ will be free from defects in materials and workmanship for two years from the date of purchase White Matter will repair or replace any nanoZ product or part thereof which upon inspection by White Matter is found to be defective in materials or workmanship The nanoZ must be returned to the Distributor from which it was bought together with proof of purchase A return authorization must be obtained from the Distributor in advance of return Please include a brief description of any claimed defect s The customer shall be responsible for all costs of transportation and insurance to the Distributor The Distributor will cover the return shipping costs This warranty shall be void and of no force of effect in the event the nanoZ has been modified in design or function or subjected to abuse misuse mishandling or unauthorized repair Water or other liquid related damage is specifically excluded from this warranty Furthermore product malfunction or deterioration due to normal wear is not covered by this warranty 34
33. nanoZ User Manual Disclaimer Information in this document is subject to change without notice No part of this document may be reproduced or transmitted without the express written permission of White Matter LLC While every precaution has been taken in the preparation of this document the publisher and the author assume no responsibility for errors or omissions or for damages resulting from the use of information contained in this document or from the use of programs and source code that may accompany it In no event shall the publisher and the author be liable for any loss of profit or any other commercial damage caused or alleged to have been caused directly or indirectly by this document Distributed by Tucker Davis Technologies 11930 Research Circle Alachua FL 32615 USA Phone 386 462 9622 Fax 386 462 5365 e mail info tdt com March 2010 2009 2010 White Matter LLC All rights reserved Table of Contents Werom 0 g aor TE 1 RK EE Ee 1 SEENEN 2 EE 2 Eelere 3 Probe Ee e 4 CAI UE OTA e 4 W 6 BEE 6 Ee eet 7 EE 7 Probe ee 8 Report WInNdOW een ee eran eens ore a ee ee ee E ee ee 9 Operatine MODES eegene 11 fe COMET ON krute 11 Impedance ESE WOT E 12 DC electroplate mode csicccscccssssseiesesscsssecosseasscscseesessevseosenccasssedecsseseseteosceessntasusedeensstsnsedvecssesenennonssetueseovevsnevenrelie 13 Impedance e Ee en Une 14 Ara ON OE aa am Urner arrears an rrr ererertt enee et sr seer ern tee
34. ndow can be used to select a subset METET CER of electrode sites for testing or electroplating You can select and deselect one or multiple electrode sites using the mouse Double clicking the left mouse button selects or deselects all sites Selected site numbers are displayed in green deselected sites are displayed in grey The current site selection applies to all automated modes of operation but not the Manual Control mode channel selector The Probe window can also be used to visualize impedance test results according to the probe site layout which is more intuitive than interpreting tabular results Once a probe has been tested holding down the right mouse button highlights the condition of every recording site red for short blue for open green for normal according to the settings in the Report window With the right mouse button held down moving the mouse pointer over individual electrode sites will display a small pop up window with the measured impedance magnitude and phase for that site N2T A2 42 tet 3mm 150 150 312 Report window When using any of the automated modes CH Condition FOR r ame x2 tet 3mm 150 150 Short 20 k vl Phase of O p e rati O n 7 th e n a n oZ sto re S te st bne e Gerbe 5 Open 5o000 k Ster results in an Excel like spreadsheet Last tested 08 12 2009 at 8 51 47 AM 75 of sites good MV Condition 1004 Hz 2 389u Mag MOhm Phase hh mm ss 57 909 ban 00 00 05 0 006 2 4 00 00
35. negative current for 250ms immediately followed by a 2uA electrode positive current for 750ms The post plating site impedance will then be measured and the nanoZ will advance to the next selected electrode site Clicking on Activate probe again or pressing ESC at any time will pause the activation and you will be given the option of skipping the current electrode Ignore continuing or stopping The pre and post activation impedance test results in the Probe report can be saved by clicking the kl icon Matlab Software Development Kit The nanoZ Matlab SDK allows users to program customized nanoZ applications that are not supported by the bundled Windows program To use the Matlab SDK you should have a licensed copy of Matlab installed on the host PC version 2006a or later and have the nanoZ SDK installed refer to the Software Installation section of this User Manual nanoz MEN library MATLAB applications can access the nanoZ through the nanoz MEX files Two versions are provided one each for 32 and 64 bit versions of Matlab running under Windows nanoz mexw32 and nanoz mexw64 respectively A MEX file can contain only one Matlab function and because the nanoZ SDK provides multiple functions the actual function names are passed as the first argument when calling the nanoz gateway function The following syntax is used for all function calls lt output gt nanoz function name argl arg2
36. next few lines defines the shape of the adaptor as displayed in the Adaptor window Typically this will define one or two rectangles representing one or both of the nanoZ s Samtec connectors however it can be any shape The NumPoints field specifies the number of points that comprise the adaptor outline The format for these points is Outline x y where _ is an arbitrary suffix and x amp y are 2D pixel coordinates The outline must form an enclosed region Repeating the same Outline coordinates on _ two consecutive lines indicates that this is the last point in that shape with subsequent Outlines representing the next shape For example with the NZA DIP16 adaptor shown here on the left the single rectangle requires 6 points with the last two points Outline4 Outline5 having the same coordinates as OutlineO to complete the rectangle Unless you require an adaptor with a special shape it is probably simplest to just copy and paste this section from one of the existing 32 or 64 channel adaptors as required 5 the last section of the adaptor definition is the most important as it defines the mapping from the nanoZ s internal MUX to the pins of the adaptor The NumChans field specifies the number of adaptor channels to map The format for the mapping is MUX n x y where n is the nanoZ MUX channel 1 64 and x and y define the pin location on the Adaptor window The ordinal position defines the adaptor pin number So for exampl
37. nsure accurate results regularly check the signal quality using the Scope display of the nanoZ application It is recommended to keep the electrode and reference connections as short as possible Long wires may also distort results due to their capacitance Avoid open ends which act as antennas If necessary wrap wire mesh or aluminum shielding around the setup and ground the shield to the reference clip In especially noisy environments it may also help to run the nanoZ from a battery powered laptop Particular care should be taken not to expose the nanoZ to liquids of any kind It liquid gets splashed on the nanoZ wipe it off with a moist cloth and allow to dry If solution gets spilled inside the nanoZ immediately unplug it and remove any attached electrodes or electrode adaptors For water spills allow the nanoZ to dry completely before resuming use For saline or other solutions remove the two screws that secure the end cap closest to the probe connector Slide out the printed circuit board being careful not to damage the probe connector on the enclosure opening Flush with distilled water to remove all traces of the spillage and allow the circuit board to completely dry before re assembling the nanoZ Firmware updates Follow these instructions to update the firmware on your nanoZ 1 Plug in the nanoZ and run the nanoZ application 2 Select Help Update firmware from the Main Menu 3 Click File to select the new firmware e g
38. odes of operation for performing a variety of different tasks These modes can be selected by clicking a button on the left pane of nanoZ application or via the Mode menu on the Main Menu The following instructions assume that a suitable electrode adaptor and probe configuration have been chosen and the electrode sites of interest have been selected in the Probe window The screenshots below were taken from Windows XP The appearance of the user interface may vary depending on the version of Windows you are using Manual control mode This mode provides manual control of the nanoZ s site selection impedance testing and DC constant current electroplating functions No adaptor O Dmm Probe not selected C Scope CH1 Ger Trig A volate B C Ge L t peut thins Oof Channel Testmeq gt 41 z Hz Impedance off Current level r 2 D Manual control O Current es L j d One shot 1 lt gt v 0 084uA LA 541 1 Hz Selecting Impedance A will continuously measure the impedance of the currently selected channel B at the specified Test freq C The impedance in Mohms and phase angle in degrees will be displayed on the DMM If One shot is checked a single impedance measurement will be made To stop continuous impedance measurements select Off A Selecting Current A mode will apply a DC constant current to the currently selected channel B at the level indicated adjacent to the Current level sli
39. r a small beaker of saline or plating solution With this setup it is easier to put the beaker on a height adjustable laboratory jack and raise or lower the jack to immerse the probe in the solution rather than adjusting the height of the nanoZ on the stand Alternatively remove the screw on the nanoZ adjacent to the future I O port and replace with a threaded rod 3 40mm outer thread diameter attached to a micromanipulator This setup is ideal for in vivo applications To use the nanoZ with in vitro dish electrodes such as MEAs from Multi Channel Systems attach the supplied stick on feet to the underside of the nanoZ Place the nanoZ on a flat surface plug the MEA adaptor into the nanoZ and plug the MEA into the adaptor Fill the MEA well with saline or plating solution A piece of platinum wire immersed in the bath solution makes an ideal reference connection as does a silver silver chlorided wire or other inert metal If the probe is connected directly to the nanoZ e g a NeuroNexus A32 or A64 packaged probe use a short jumper wire to connect one of the G pins on the probe PCB to the bath electrode If using a NZA series adaptor such as the NZA DIP16 connect the bath electrode to the adaptor using the 3 pin alligator cable supplied Care should be taken to protect your setup from electromagnetic interference EMI The nanoZ is susceptible to EMI because it uses very small test signals for measuring impedance To e
40. sion Returns the version of the nanoz MEX file Usage major version minor version nanoz getversion Arguments none Return values major version minor version major and minor versions of the currently installed nanoz MEX file respectively enumdevs Enumerates attached nanoZ devices Usage devs nanoz enumdevs Arguments none Return value devs cell array of strings one string per each attached device containing the device specific serial numbers Remarks If a device is attached but already opened by this MEX file or another application it will not be enumerated An empty cell array is returned if no devices are attached or available open Opens and allocates a free nanoZ device for access by other functions Usage handle nanoz open serial number Arguments serial number string device serial number which can be obtained using the enumdevs function Return value handle number handle to the opened device to be used to access all other device functions Remarks If a nanoZ device with a given serial number is not attached or is already opened by this MEX file or another application this function will fail nanoZ User Manual close Closes an opened nanoZ device and releases system resources Usage nanoz close handle Arguments handle handle to an opened device returned by the open function Return values none Remarks User Matlab programs
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