tektronix tdsjit1
Contents
1. Histogram On Off i Autoscale Center 500 0ms ales Histogram Period After all application menu parameters have been set as darivad Figure 20 Histogram format menu part 2 Display Resolution Medium vertical pur Store Histogram In Value at V Bar To view the vertical values press Value at V Bar side after you have taken a measurement Press CURSOR V Bar side to display the cursors Profile Format Setup You can define the appearance of the results in the Profile format To do so follow these steps 1 Press Profile main On Off side to enable or disable the format You define the format in the remaining menu items See Figure 21 and Figure 22 TDSJIT1 Jitter Analysis Application User Manual 27 Setup Parameters 28 2 Press Profile Height side and select the height of the profile in number of divisions The range of height values is from 0 5 division to 8 divisions in 0 5 division increments 3 Press Reset Profile side to clear all values used to define the Profile format 4 Press Store Profile In side and select the reference waveform in which to store the profile information Refl Ref2 Ref3 or Ref4 5 Press Profile Length side and select the number of points in the reference waveform in which the format information 1s saved as 500 1000 2500 5000 or 15000 Tek Run 500kS s Sample Period2. Duty Cycle 38 Frequency 36 N Cycle 37 Period 35 Pulse Width 37 Skew 39 application test method 34 Continue 8 descriptions 33 guidelines Cycle to Cycle 36 Duty Cycle 38 Frequency 36 N Cycle 37 Period 35 Pulse Width 38 Skew 39 41 Index localizing 31 oscilloscope changes 8 Pause 8 setup parameters duo waveform measurements 29 single waveform measurements 24 starting 7 turning off display 9 tutorial lessons 11 menu Control 8 overview 21 messages Warning 34 N N Cycle measurement application equations 37 guidelines 37 tutorial lesson 12 O online help 6 oscilloscope compatibility 1 P Pause side menu 8 Period measurement application equations 35 guidelines 35 tutorial lesson 12 product compatibility 1 description 1 requirements 2 restrictions 2 updates 2 Profile format 10 setup parameters 27 turning off 9 tutorial lesson 15 Pulse Width measurement application equations 37 guidelines 38 tutorial lesson 12 Q quitting the application 10 42 R readout turning off 9 recalling a setup 23 tutorial lesson 20 reference waveforms loading 11 Reset All 8 S saving a setup 23 tutorial lesson 19 setup parameters duo waveform measurement 29 single waveform measurements 24 setups recalling 23 saving 23 Single acquisition mode 8 Skew measurement application equations 39 guidelines 39 tutorial lesson 17 starting ap
3. Pk Pk Population Stop Reset All EN 2 Measure Setup Histogram Profile Control Utilit Skew Skew Ref2 Ref1 Ready Y Figure 13 Skew lesson Statistics readout 7 To display the other formats follow steps 4 through 22 on page 13 These steps include how to view individual measurement values and remove the formats from the display Figure 14 shows the results in the Histogram format Tek Run 100kS s Sample E Control Mode Skew Mean StdDev Max Min Pk Pk Population stop Reset All ga Measure Setup Histogram Profile Control un Skew Skew Ref Refl Ready Utility Figure 14 Skew lesson Histogram format 18 TDSJIT1 Jitter Analysis Application User Manual Tutorial Figure 15 shows the results in the Profile format Tek Run 100kS s Sample E Control Mode Population Measure i Profile Control Ref2 Ref1 Skew Ready Utility Figure 15 Skew lesson Profile format Saving a Setup and Exiting the Application You might need to save the oscilloscope setup and the application setup To save the oscilloscope setup refer to the user manual for your oscilloscope The procedure varies between models The setup is always saved in the APPS TDSJITI TEMP directory on the oscilloscope To save the application setup follow these steps 1 Press the SHIFT and then the APPLICATION button to return to
4. TDSJIT1 Jitter Analysis Application User Manual 37 Measurement Descriptions Procedure To set up the Pulse Width measurement follow these steps 1 Press Measure main N Cycle side 2 To select the channel reference or math waveform to be measured press Pulse Width Setup main Input side 3 Follow steps 3 through 6 on page 35 Duty Cycle Measurement The Duty Cycle measurement calculates the ratio of the positive or negative portion of the cycle relative to the period Definition The Duty Cycle measurement is calculated using the following equations Dj W P D W P Where D is the positive duty cycle D is the negative duty cycle W is the positive pulse width W is the negative pulse width P is the period Procedure To set up the Duty Cycle measurement follow these steps 1 Press Measure main gt Duty Cycle side 2 To select the channel reference or math waveform to be measured press Duty Cycle Setup main Input side 3 Follow steps 3 through 6 on page 35 38 TDSJIT1 Jitter Analysis Application User Manual Measurement Descriptions Skew Measurement The Skew measurement calculates the difference in time between the designated edge on a principal waveform to the designated edge on another waveform Definition The Skew measurement is calculated using the following equation S T T Where S is the period T is the edge of the principal waveform after t
5. Tutorial Taking Measurements from Two Waveforms In this example you learn how to use the application to calculate the difference in time between a designated edge on a principal waveform and a designated edge on another waveform NOTE The results of the Skew lesson is a pulse width value The object of the lesson is to make you familiar with setting up a Skew measurement To measure a pulse width you would typically use the Pulse Width measurement To become familiar with the Skew jitter measurement follow these steps 1 B N Press Measure main gt more 1 of 2 side gt Skew side Press Setup Skew main From Input side and select Ref3 Press To Input side and select Ref3 See Figure 12 Press To Edge side gt Slope side and select Fall Press Done side Tek Run 100kS s Sample Skew After all application menu parameters have been set as desired Press Control Start to execute the measurement Figure 12 Setup Skew menu TDSJIT1 Jitter Analysis Application User Manual d i Measure Histogram Profile Control ns Skew ETE Reta Ref1 Ready Utility i d To DX Setup Skew From Input To aH From Display Statistics 17 Tutorial 5 To take the measurement press Control main gt Start side 6 Wait for the calculations to complete Figure 13 shows the Statistics readout Skew Mean StdDev Max Min
6. After all application menu parameters have been set as Ancirad Figure 21 Profile format menu part 1 Tek Run 500kS s Sample l E Profile On Off Ei Profile Xn Value at Reset Profile Figure 22 Profile format menu part 2 E Profile Store Profile In Rett Profile TDSJIT1 Jitter Analysis Application User Manual Setup Parameters 6 Press Value At side after taking a measurement to view the vertical values by index number You can approximate the index number based on 50 per horizontal division N Cycle The N cycle measurement has an additional menu item in the setup menu Press Cycle Separation N side and use the GP knob to select the number of cycles between the cycles that will be measured Duty Cycle The Duty cycle measurement has an additional menu item in the setup menu Press Polarity side and select the polarity on which to start the measurement Positive or Negative Duo Waveform Measurements The Skew measurement compares the difference in time between a designated edge on a principal waveform and a designated edge on another waveform After a measurement is complete the results appear in a Statistics readout and are saved in a graphical format if enabled To set up the Skew measurement follow these steps 1 Press Measure main Skew side to select the measurement 2 Press Setup Skew main and use the Setup menu to define the
7. INI file will contain the stored settings Once you have saved a setup that setup will be recalled whenever you start the Jitter Analysis Application NOTE If you want to save the existing configuration you must use the Save Setup feature to store the present application settings TDSJIT1 Jitter Analysis Application User Manual 23 Setup Parameters You can recall the settings in the HDO APP TDSJIT1 TEMP TDSJIT1 INI file at any time To do so press Utility main Recall Setup side m To recall the factory default menu settings press Utility main Default Setup side The Jitter Analysis Application Save Recall function is totally independent of the primary oscilloscope Save Recall function stored in nonvolatile RAM Single Waveform Measurements 24 The Period Frequency Cycle to Cycle N Cycle Pulse Width and Duty Cycle measurements compare the random or systematic variation of timing relation ships of two events on one input waveform After a measurement is complete the results appear in a Statistics readout and are saved in a graphical format if enabled Although this description uses the Period measurement it also applies to the Frequency Cycle to Cycle and Pulse Width measurements if you substitute one of these measurements for Period in steps 1 and 2 This description also applies to the N Cycle and Duty Cycle measurements However these measurements require some additional set up Figur
8. eee eee 37 Duty Cycle Measurement 0 0 0 cee eee eee tees 38 Skew Measurement 0 00 T EA A A aE eee 39 TDSJIT1 Jitter Analysis Application User Manual Table of Contents List of Figures Figure 1 TDSJIT1 Jitter Analysis Application Figure 2 Starting the application ee Figure 3 Jitter Analysis Application initial display Figure 4 Returning to the application Figure 5 The Control menu ooooooooooomoo moro Figure 6 Setup Period menu basic setup menu Figure 7 Period lesson Statistics readout Figure 8 Histogram format menu eeeese Figure 9 Period lesson Histogram format Figure 10 Profile format menu eere Figure 11 Period lesson Profile format Figure 12 Setup Skew menu eere Figure 13 Skew lesson Statistics readout Figure 14 Skew lesson Histogram format Figure 15 Skew lesson Profile format Figure 16 Application menu structure eese Figure 17 Save Setup and Recall Setup selections in the Utility menu Figure 18 Cycle Start Edge menu oo ooooooo oo o Figure 19 Histogram format menu part 1 Figure 20 Histogram format menu part 2 Figure 21 Profile format menu part1 Figure 22 Profile
9. margin in graticule divisions above and below the Level threshold which the voltage must cross to be recognized as changing Press Done side The specified values are loaded for the measurement Tek Run 500kS s Sample E Setup Skaw From input To Input From Edge l To Edge After all application menu Roo deu Rise 0 0 parameters have been set as desired Skew D sett a ects Display Press Control Start to execute T Ov Statistics the measurement Measure Histogram Profile Control i Skew EN of Off Ready Utility Figure 23 Setup Skew menu TDSJIT1 Jitter Analysis Application User Manual Setup Parameters NOTE The application detects the minimum and maximum voltage levels of the waveform If the voltage level plus or minus the hysteresis falls outside of 2 596 to 97 596 of the waveform peak to peak range no measurement is taken 7 Descriptions on how to set up the Histogram and the Profile graphical formats start on page 26 8 After the measurement is set up press Control main Start side If you enabled the Statistics readout when the measurement is complete the readout values display or update If you enabled a graphical format the results are saved in the selected reference waveform and do not display To display the results in the Histogram format follow step 7 on page 14 To display the results in the Profile format follow step 18 on page
10. or Duty Cycle side To take measurements of the difference in time between two edges on two waveforms select Skew side The name of the Measure main menu changes to match the selection In the setup menu select or specify values for parameters associated with or required by the selected measurement See Setup Parameters on page 23 The application warns you if the setup is not adequate for the measurement By default the results appear as numeric values in the Statistics readout To view the results graphically you need to access the Histogram or Profile menu enable the format and specify parameters to customize the format See Viewing the Results on page 9 If you want to change trigger settings or localize the measurement see Localizing Measurements on page 31 do so now The application defaults to the level setting as specified in the Cycle Start Edge menu item of the setup menu Figure 18 on page 25 shows an example of the Cycle Start Edge menu item Functional Overview 6 Press Control main Figure 5 shows the Control menu Tek Run 100kS s Sample Control Mode Period T Stop After all application menu parameters have been set as desired Press Control Start to execute f oW RS the measurement 2 f Measure Setup Histogram Profile Control TR Period Period of Off Ready utility Figure 5 The Control menu 7 Press Mode side to select Single or Free Run acqui
11. the application Press Utility main Save Setup side Press Save to Selected File side To exit the application press Utility main Exit side To confirm press OK side TDSJIT1 Jitter Analysis Application User Manual 19 Tutorial Recalling a Setup To return to the tutorial setup you can recall the saved oscilloscope setup from the hard disk You will also need to restart the application To recall the oscilloscope setup refer to the user manual for your oscilloscope The procedure varies between models To recall the application setup follow these steps 1 Start the application as described on page 5 2 Press Utility main Recall Setup side 20 TDSJIT1 Jitter Analysis Application User Manual CAS AAA A Reference Menu Structure Figure 16 shows the relationship of the application menus Period Setup Period Input Type Slope Measure Frequency also F requency Cycle Start Edge Edge Level Cycle Cycle amp Cycle Cycle Display Statistics Hysteresis N Cycle Done Skew ei Pulse Width Input Duty Cycle Setup N Cycle Cycle Separation N E Cycle Start Edge Display Statistics Setup From Input Iz To Input On Off From Edge Histogram Autoscale Setup Skew To Edge Center Display Statistics Span Baia Display Resolution Vertical Display A Input Store Histogram In Setup Pulse Width Pulse Start Edge Value at V Bar Displa
12. waveforms between which to measure skew periods and where to start and end the measurement Figure 23 shows the Setup Skew menu 3 Press From Input side and select the channel reference waveform or math waveform on which to start to take the measurement NOTE If you select a reference or math waveform you will need to display the waveform before a measurement can be taken To display the waveform press the MORE button and the appropriate main item 4 Press To Input side and select the channel reference waveform or math waveform on which to end the measurement 5 Press From Edge side and specify where to start the measurement Press Slope side and select the edge on which to start the measurement Rising or Falling TDSJIT1 Jitter Analysis Application User Manual 29 Setup Parameters 30 Press Level side and specify where on the slope in Volts to set the measurement threshold Press Hysteresis side and select the margin in graticule divisions above and below the Level threshold which the voltage must cross to be recognized as changing Press Done side The specified values are loaded for the measurement Press To Edge side and specify where to end the measurement Press Slope side and select the edge on which to end the measurement Rising or Falling Press Level side and specify where on the slope in Volts to set the measurement threshold Press Hysteresis side and select the
13. 15 Figure 9 on page 14 shows an example of the Histogram format and Figure 11 on page 16 shows an example of the Profile format Localizing Measurements You can control the amount of data to measure by adjusting the Record Length or Horizontal Scale in the oscilloscope horizontal menu or the Trigger Position By specifying the trigger position the starting point and the total length of the measurement you can effectively size the area of interest NOTE If an error message displays because there are not enough cycles from which to take a measurement you should increase the Record Length TDSJIT1 Jitter Analysis Application User Manual 31 Setup Parameters 32 TDSJIT1 Jitter Analysis Application User Manual A EE SE Measurement Descriptions This section contains descriptions of the measurements available in the Jitter Measurements Application This section includes information on the equations used to take each measurement and the algorithms each follows There are seven measurements Period Frequency Cycle to Cycle N Cycle Skew Pulse Width and Duty Cycle Figure 24 shows an example of the results from a Period measurement and the three ways to display the results Statistics readout Period Mean StdDev Max Min Pk Pk Population Profile format Figure 24 Example of a Period measurement and the results Measurements will continuously update if you select the Free Run mode in the Control menu befo
14. HETHER TEKTRONIX OR THE VENDOR HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES AAA D Table of Contents Related Documentation sisian 0 cece eee cnt e ia vii GoOnventiOns xe Pisa haben did te eu eto wt vds vii Contacting Tektronix asiri 42 nan ir nete an whan ides viii Getting Started Product Description 0 cece cece cc cece cece eee nenne 1 Compatibility sr 8 22 AA SA ei ee eL LI sets s 1 Requirements and Restrictions 0 00 cece cee eee eee eens 2 Updates cs cas cites hee Sie eee be ee Bea t eve 2 ACCESSOMES iis pee boa SUE a BE Ce ie VR 2 Installation ner gia EU ei an 3 Installing the Application lssssseseseeleese I 3 Updates Through a Web Browser 0 cece eee eee nA 4 Equipment Under Test Connections eese 4 Operating Basics Functional Overview o oooococcoocroccorocccncrnonocnno n 5 Starting the Application oooooooooooooororr ee 5 Using the Local Help 2 0 0 ccc Ih 6 Using Other Functions 2 22 0 00 cece n 6 Taking a Measurement 0 n 7 Viewing the Results ooooooooooorororrr n 9 Statistics Readout olera BEA ea ne Reis detur eod 9 Histogram Graphical Format oooooooocooocor or 9 Profile Graphical Format 0 0 0 cee o 10 Exiting the Application lsssseseeeee e Ih 10 Tutorial eei rd tere Ri E E ux e 11 Setting Up the Oscilloscope o0ooooooooorororo
15. The application detects the minimum and maximum voltage levels of the waveform If the voltage level plus or minus the hysteresis falls outside of 2 596 to 97 596 of the waveform peak to peak range no measurement is taken 5 Press Statistics Readout side to enable or disable the Statistics Readout Tek EE 100kS s E Cycle Start Edge iud Level 0 0 Y Y ste resis Period TIES Done After all application menu parameters have been set as desired i i ICH 1 10 0mV Press Control Start to execute fo E i 0 v the measurement Measure CO Histogram Profile control a Period Period of Off Ready Utility Figure 18 Cycle Start Edge menu 6 To enable and define the appearance of results in a graphical format refer to Histogram Format Setup on page 26 and Profile Format Setup on page 27 7 After the measurement is set up press Control main Start side If you enabled the Statistics readout when the measurement is complete the readout values display or update TDSJIT1 Jitter Analysis Application User Manual 25 Setup Parameters Histogram Format Setup 26 If you enabled a graphical format the results are saved in the selected reference waveform and do not display To display the results press the MORE button and the appropriate reference waveform Figure 9 on page 14 shows an example of the Histogram format and Figure 11 on page 16 shows an exampl
16. User Manual Tektronix Y TDSJIT1 Jitter Analysis Application 071 0527 00 This document applies to software version 1 0 0 and above Warning The servicing instructions are for use by qualified personnel only To avoid personal injury do not perform any servicing unless you are qualified to do so Refer to all safety summaries prior to performing service Copyright O Tektronix Inc All rights reserved Licensed software products are owned by Tektronix or its suppliers and are protected by United States copyright laws and international treaty provisions Use duplication or disclosure by the Government is subject to restrictions as set forth in subparagraph c 1 ii of the Rights in Technical Data and Computer Software clause at DFARS 252 227 7013 or subparagraphs c 1 and 2 of the Commercial Computer Software Restricted Rights clause at FAR 52 227 19 as applicable Tektronix products are covered by U S and foreign patents issued and pending Information in this publication supercedes that in all previously published material Specifications and price change privileges reserved Printed in the U S A Tektronix Inc P O Box 1000 Wilsonville OR 97070 1000 TEKTRONIX and TEK are registered trademarks of Tektronix Inc WARRANTY Tektronix warrants that the media on which this software product is furnished and the encoding of the programs on the media will be free from defects in materials and workmanship for a
17. al To load the reference waveform file follow these steps 1 Press WAVEFORM gt Recall Wfm to Ref main gt Recall from file side Use the general purpose GP knob to select hd0 and press SELECT Use the GP knob to select WFMS and press SELECT 2 3 4 Use the GP knob to select SIGSOMHZ WFM and press Ref 3 active side 5 Press MORE Ref 3 main to display the waveform 6 Press the SHIFT and then the APPLICATION front panel menu button to return to the application TDSJIT1 Jitter Analysis Application User Manual 11 Tutorial Taking Measurements from One Waveform 12 In this example you learn how to use the application to calculate the duration of a cycle as defined by a start and a stop edge You will view the results in the Statistics readout and the both graphical formats NOTE This lesson uses the Period measurement The objective of the lesson is to make you familiar with how to set up all measurements from one waveform Period Frequency Cycle to Cycle N Cycle Pulse Width and Duty Cycle To become familiar with a measurement from one waveform follow these steps 1 Press Setup Period main Input side and select Ref3 See Figure 6 Tek Run 100kS s Sample Cycle Start Edqe Period Mean StdDev Display Statistics Measure Setup i Control zh Period Period e Off Ready Utility Figure 6 Setup Period menu basic setup menu 2 To take the
18. ariation of timing measurements as values in a Statistics readout or graphically in a Histogram or a Profile format If you want to display the results in a graphical format the information is placed in a reference waveform selected in the Histogram or the Profile menu To view the Histogram or Profile after a measurement press MORE Ref main to view the formatted results NOTE Stop the acquisition before viewing the results in a graphical format if you are operating the oscilloscope in the Free Run acquisition mode By default the measurement results appear in the Statistics readout The Statistics readout contains values for the mean standard deviation StdDev peak to peak Pk Pk maximum Max and minimum Min values and Population the number of cycles used to calculate the values There are two ways to view parts of the waveform that are obscured by the Statistics readout You can push the CLEAR MENU button or access the setup menu for the measurement and set the Statistics Readout menu item to off The Histogram graphical format is a bar graph that represents the distribution of timing measurements The horizontal axis where you can specify the center and span represents the measurement values and the vertical axis represents the number of times that the value occurred NOTE Use the Horizontal SCALE knob to adjust the horizontal scale of the waveform to fit the screen for proper viewing TDSJIT1 Jitter A
19. ce section Starting the Application You can start the Jitter Analysis Application after it has been installed in the oscilloscope To start the application follow these steps 1 Press SETUP gt Select Application main 2 Use the general purpose GP knob to select hd0 and press SELECT 3 Use the GP knob to select the TDSJIT1 APP title as shown in Figure 2 and press Activate Application side Use to choose i Press SELECT to change 1 47 Select Directory hd0 Free 153 5ME Application Td0 hdo APP 98 10 30 WFMS 98 10 30 TDSDDM1 APP 98 10 30 TDSPRT1 APP 98 10 30 TDSPWRI APP 98 10 30 TDS 99 01 05 Tek Run T00kS s Sample amp E Activate Application eca ave eca File Saved Current Factory Anal Utilities Setup Setup Setup i Figure 2 Starting the application TDSJIT1 Jitter Analysis Application User Manual 5 Functional Overview The application starts up and displays as shown in Figure 3 Tek Run 100kS s Sample Period After all application menu parameters have been set as desired Press Control Start to execute the measurement Measure Setup Period Period Figure 3 Jitter Analysis Application initial display Using the Local Help Profile off Control Measure Period Frequency Cycle Cycle N Cycle V Ready Utility The application incl
20. croll through the files to the TDSJITI application select the file and download it to your hard disk drive If necessary unzip the file 3 Copy the application from the hard disk to a blank DOS formatted floppy disk 4 Follow the Installing the Application procedure on page 3 Equipment Under Test Connections A You can use any compatible probe to connect between your EUT equipment under test and the oscilloscope The connection is usually to a clock signal The Skew measurement requires two channels or two reference waveforms WARNING To avoid electric shock you must ensure that power is removed from the EUT before attaching a probe to it Do not touch exposed conductors except with the properly rated probe tips Refer to the probe manual for proper use Power down the EUT before connecting the probe to it Table 1 shows the default channel to waveform assignments Table 1 Channel assignments Channel or reference Waveform assignment Chl Main waveform such as the Clock signal Ch2 Skewed waveform Refl Profile graphical format Ref2 Histogram graphical format TDSJIT1 Jitter Analysis Application User Manual EX d AAA Operating Basics DE Functional Overview This section contains descriptions of the basic functions of the Jitter Analysis Application and how to use the functions Further details about the basic functions and descriptions of more advanced features are included in the Referen
21. ds Updates You can find information about this and other applications at the Tektronix Inc web site http www tektronix com Measurement scopes index html in the Software and Drivers category Check this site for application updates that you can download and for free applications Accessories There are no standard accessories for this product 2 TDSJIT1 Jitter Analysis Application User Manual AA l Installation This application resides on a floppy disk You can download updates if any from the Tektronix ftp site through a web browser NOTE To operate the Jitter Analysis Application the TDS Run Time Environment VI 1 or above must be installed on your oscilloscope Installing the Application To install the application from the floppy disk to your oscilloscope follow these steps 1 Power off the oscilloscope NOTE Additional information about the application or installation is located in a Readme txt file on the floppy disk You should insert the floppy disk into a DOS based personal computer and read the Readme txt file before you continue If you are updating the application the Readme txt file on the Tektronix ftp site supercedes the Readme txt file on the floppy disk 2 Insert the disk in the floppy disk drive and power on the oscilloscope NOTE To verify that the TDS Run Time Environment V1 1 or above is installed watch for the name to ap
22. e 3 on page 6 shows the initial display after selecting the Period measure ment To set up a jitter measurement on one waveform follow these steps 1 Press Measure main Period side to select the measurement 2 Press Setup Period main Use the Setup menu to define the waveform on which to measure period duration and where to start and end the measure ment See Figure 6 on page 12 3 Press Input side and select the channel reference waveform or math waveform on which to measure period duration NOTE If you select a reference or math waveform you will need to display the waveform before a measurement can be taken To display the waveform press the MORE button and the appropriate main menu item 4 Press Cycle Start Edge side and specify the slope level and hysteresis to define where to start and stop the measurement of each period See Fig ure 18 Press Slope side and select the edge on which to start the measurement Rising or Falling TDSJIT1 Jitter Analysis Application User Manual Setup Parameters Press Level side and specify where on the slope in Volts to set the measurement threshold Press Hysteresis side and select the threshold margin in graticule divisions relative to the Level which the voltage must cross to be recognized as changing The margin is the Level plus or minus half the hysteresis Press Done side The specified values are loaded for the measurement NOTE
23. e of the Profile format You can define the appearance of the results in the Histogram format To do so follow these steps 1 Press Histogram main On Off side to enable or disable the format You define the format in the remaining menu items See Figure 19 and Figure 20 NOTE You should acquire measurements with a population greater than three before you use Autoscale Press Autoscale side The Center side menu item will be set to the Mean value and the Span side menu item will be set to 2 1 times the Max minus Mean or Mean minus Min value whichever is larger Press Center side and specify the value for the horizontal center position of the histogram The range varies by measurement Press Span side and specify the total horizontal range that the histogram covers The range varies by measurement Press Display Resolution side and select the resolution as defined by bins to be High 500 bins Medium 50 bins or Low 20 bins Press Vertical Display side and select the vertical axis to be linear or logarithmic Press Store Histogram In side and select the reference waveform in which to store the histogram information Refl Ref2 Ref3 or Ref4 TDSJIT1 Jitter Analysis Application User Manual Setup Parameters Tek Run 300kS s Sample Period After all application menu parameters have been set as darivad Figure 19 Histogram format menu part 1 Tek Run 300kS s Sample
24. ff side to select On Refl appears under Profile to indicate that the results will be stored in Refl See Figure 10 Tek Run 100kS s Sample E Profile On Off Profile je Zeh Yalue at E Resat Profile Max Min Pk Pk Population more 1of2 Measure Setup Histogram Profi Control TM Period Period Ref Ref1 Ready utility Figure 10 Profile format menu 17 18 19 Press Control main Start side to retake the measurements To display the Profile graphical format follow these steps a Press the MORE button b Press Refl to display the Profile format Press the SHIFT and then the APPLICATION button TDSJIT1 Jitter Analysis Application User Manual 15 Tutorial 16 Figure 11 shows the results in the Profile format Tek Run 100kS s Sample E Control Mode Population Measure Setup i Profile Control su Period Period Ref2 Ref1 Ready Utility Figure 11 Period lesson Profile format 20 21 22 Press Profile main Value at side to view the measurement values by index number Use the GP knob to scroll through the values You can approximate the index number based on 50 per horizontal division Vertical cursors do not need to be displayed Press the MORE and then the WAVEFORM OFF button Press the SHIFT and then the APPLICATION button TDSJIT1 Jitter Analysis Application User Manual
25. fference between adjacent periods P is the period To set up the Cycle to Cycle measurement follow these steps 1 Press Measure main gt Cycle to Cycle side 2 To select the channel reference or math waveform to be measured press Cycle to Cycle Setup main Input side 3 Follow steps 3 through 6 on page 35 TDSJIT1 Jitter Analysis Application User Manual Measurement Descriptions N Cycle Measurement The N Cycle measurement calculates the difference in period measurements from cycles that are a defined number of cycles apart Definition The N Cycle measurement is calculated using the following equations ANP T cow T T iow T Where ANP is the difference between adjacent N cycle periods Procedure To set up the N Cycle measurement follow these steps 1 Press Measure main N Cycle side 2 To select the channel reference or math waveform to be measured press N Cycle Setup main Input side 3 Follow step 3 on page 35 4 Press Cycle Separation N side You can specify the number of cycles between the period measurements 5 Follow steps 4 through 6 on page 35 Pulse Width Measurement The Pulse Width measurement calculates the difference in time between the rising and falling edges of a pulse Definition The Pulse Width measurement is calculated using the following equations Where Wis the pulse width T is the time location of the opposite polarity edge
26. format menu part 2 Figure 23 Setup Skew menu eere Figure 24 Example of a Period measurement and the results TDSJIT1 Jitter Analysis Application User Manual oo lA A un 13 13 14 15 16 17 18 18 19 21 23 25 27 27 28 28 30 33 Table of Contents iv TDSJIT1 Jitter Analysis Application User Manual fcm EU I Ii General Safety Summary Symbols and Terms A TDSJIT1 Jitter Analysis Application User Manual Review the following safety precautions to avoid injury and prevent damage to this product or any products connected to it To avoid potential hazards use this product only as specified Only qualified personnel should perform service procedures While using this product you may need to access other parts of the system Read the General Safety Summary in other system manuals for warnings and cautions related to operating the system Connect and Disconnect Properly Connect the probe output to the measurement instrument before connecting the probe to the circuit under test Disconnect the probe input and the probe ground from the circuit under test before disconnecting the probe from the measurement instrument Do not apply a potential to any terminal including the common terminal that exceeds the maximum rating of that terminal Terms in this Manual This term may appear in this manual WARNING Warning statements identify conditions
27. he initial edge T is the edge of the second waveform nearest the principal edge of the first waveform Procedure To set up the Skew measurement follow these steps 1 2 Press Measure main Skew side To select the first channel reference or math waveform to be used in the measurement press Skew Setup main From Input side To select the second channel reference or math waveform to be used in the measurement press To Input side To specify where to start the measurement on the first waveform press From Edge side Press Slope side and specify the edge on which to start the measurement Rising or Falling Press Level side and specify where on the slope to set the measurement threshold Press Hysteresis side and specify the margin above and below the threshold which the voltage must cross to be recognized as changing Press Done side To specify where to end the measurement on the second waveform press To Edge side Press Slope side and specify the edge on which to end the measurement Rising or Falling Press Level side and specify where on the slope to set the measurement threshold TDSJIT1 Jitter Analysis Application User Manual 39 Measurement Descriptions Press Hysteresis side and specify the margin above and below the threshold which the voltage must cross to be recognized as changing Press Done side 6 If you want to localize the measurement see Localiz
28. her the Center or the Span value previous measurement results are cleared To clear the previous results press Control main Reset All side Press Start side to take retake the measurements To display the Histogram graphical format follow these steps a Press the MORE button b Press Ref2 to display the Histogram format Press the SHIFT and then the APPLICATION button Figure 9 shows the results in the Histogram format Use the Horizontal SCALE knob to adjust the horizontal scale of the waveform to fit the screen Tek Run 100kS s Sample E Control Mode Period Mean StdDew Max Min Pk Pk Population Measure Setup i Control Period Period Ref2 ff Ready utility Figure 9 Period lesson Histogram format 9 Press CURSOR V Bars side to display the vertical cursors 10 Press the SHIFT and then the APPLICATION button TDSJIT1 Jitter Analysis Application User Manual Tutorial 11 12 13 14 15 16 Press Histogram Ref2 main more 1 of 2 Value at V Bar side to view the measurement values at the vertical cursor Use the GP knob to scroll through the values Press CURSOR Off side to remove the vertical cursors from the display Press the MORE and then the WAVEFORM OFF button Press the SHIFT and then the APPLICATION button To clear the previous results press Control main Reset All side Press Profile main On O
29. ing Measurements on page 31 do so now The application defaults to the settings specified in the Trigger menu 7 Press Control main gt Start side to start the measurement 8 Wait for the measurement to complete and display the results readout 40 TDSJIT1 Jitter Analysis Application User Manual Index Index A accessories 2 application exiting 10 tutorial lesson 19 recalling a setup tutorial lesson 20 returning 6 saving a setup tutorial lesson 19 starting 5 updates 2 downloading 4 C changing settings during a measurement 8 channel assignments 4 CLEAR MENU button 9 connections 4 contacting Tektronix viii Continue side menu 8 Control menu 8 conventions vii Cycle to Cycle measurement application equations 36 guidelines 36 tutorial lesson 12 D Duty Cycle measurement application equations 38 guidelines 38 tutorial lesson 12 E exiting the application 10 F Free Run acquisition mode 8 33 Frequency measurement application equations 36 guidelines 36 tutorial lesson 12 TDSJIT1 Jitter Analysis Application User Manual G GPIB commands 8 H Help online 6 Histogram format 9 setup parameters 26 turning off 9 tutorial lesson 13 installation application 3 L leaving the application 10 lessons See tutorial lessons loading reference waveforms 11 localizing a measurement 31 Measure menu 7 measurement application equations Cycle to Cycle 36
30. measure Support ment product call toll free in North America 1 800 TEK WIDE 1 800 835 9433 ext 2400 6 00 a m 5 00 p m Pacific time Or contact us by e mail tm app supp tek com For product support outside of North America contact your local Tektronix distributor or sales office Service Contact your local Tektronix distributor or sales office Or visit Support our web site for a listing of worldwide service locations http www tektronix com For other In North America information 1 800 TEK WIDE 1 800 835 9433 An operator will direct your call To write us Tektronix Inc P O Box 1000 Wilsonville OR 97070 1000 viii TDSJIT1 Jitter Analysis Application User Manual Getting Started pem 54 Product Description The TDSJIT1 Jitter Analysis Application is a Java based application that enhances the jitter analysis capability of Tektronix TDS oscilloscopes The application offers many of the same timing measurements and two additional measurements Cycle to Cycle and N Cycle Oscilloscopes can take only one measurement in an acquisition waveform The TDSJIT1 application can take and accumulate measurements throughout an entire waveform The application can display the measurement results three ways as Statistics in a Histogram graphical format or in a Profile graphical format measurement versus measurement index numbers Figure 1 shows an example of the Histogram f
31. measurement press Control main Start side NOTE When the input is a reference waveform the measurement performs a single measurement cycle regardless of the acquisition mode TDSJIT1 Jitter Analysis Application User Manual Tutorial The Control menu main displays Control Sequencing while the application is executing When the Control menu displays Control Ready the applica tion has completed the calculations 3 Wait for the calculations to complete Figure 7 shows the Statistics readout Period a Mean 20 020ns Sta StdDev 37 108ps P Max 20 150ns Min 5 19 903ns 4 Pk P 246 42ps up Population 623 chis OV Pix Measure Setup Histogram Profile Control ni wur e er SW Ready Bu Figure 7 Period lesson Statistics readout 4 Press Histogram main gt On Off side to select On Ref2 appears under Histogram to indicate that the results will be stored in Ref2 See Figure 8 Press Autoscale side The value for Center side becomes the Mean value of the signal and the value for Span side is 2 1 times the Max minus Mean or Mean minus Min value whichever is larger Tek Run T00kS s Sample Histogram on off Autoscale Center 20 020n5 rk Figure 8 Histogram format menu TDSJIT1 Jitter Analysis Application User Manual 13 Tutorial 14 NOTE When you press Autoscale or when you change eit
32. nalysis Application User Manual 9 Functional Overview Profile Graphical Format The Profile graphical format contains consecutive values for each active measurement The vertical axis represents the measurement value and the horizontal axis represents the index number of the measurement This can be useful for observing the variation of a measurement Exiting the Application To exit the application press File Utility main Exit side To confirm press OK side 10 TDSJIT1 Jitter Analysis Application User Manual Ee MD Ml Tutorial This tutorial teaches you how to setup and take two types of jitter measurements In addition it teaches you how to exit the application and how to save and recall setups Further operating information is located in the Reference chapter Setting Up the Oscilloscope Before you start set up the oscilloscope To do so follow these steps 1 Press SETUP gt Recall Factory Setup main gt OK Confirm Factory Init side to set the oscilloscope to the default factory settings 2 Press the WAVEFORM OFF button to remove the active waveform Starting the Application To perform these lessons the Jitter Analysis Application must be installed on the oscilloscope See Installation on page 3 To start the application follow steps 1 through 3 on page 5 Loading the Reference Waveform File The application includes a reference waveform file for use with this tutori
33. or practices that could result in injury or loss of life General Safety Summary vi TDSJIT1 Jitter Analysis Application User Manual A M l Preface This manual contains operating information for the TDSJIT1 Jitter Analysis Application The manual consists of the following chapters m The chapter Getting Started briefly describes the TDSJIT1 Jitter Analysis Application and provides installation instructions m The chapter Operating Basics covers basic operating principles of the application and includes a tutorial m The chapter Reference describes how to perform specific tasks Related Documentation Your oscilloscope user manual provides operating instructions for general oscilloscope features Conventions This manual uses the following conventions m This manual refers to the TDSJIT1 Jitter Analysis Application as either the Jitter Analysis Application or as the application m When steps require that you make a sequence of selections using front panel controls and menu buttons an arrow marks each transition between a front panel button and a menu or between menus Names that are for a main menu or side menu item are clearly indicated Press VERTICAL MENU gt Coupling main DC side Bandwidth main 250 MHz side TDSJITI Jitter Analysis Application User Manual vii Preface Contacting Tektronix Product For application oriented questions about a Tektronix
34. ormat of a period measurement Tektronix TDS 784D sitio osmosore isk MIO Tek Run 100kS s Sample NN VERTICAL 4888 HORIZONTAL lt posmon gt E O VERTICAL son MENU 3000 GOSSES ON STBY 30 Figure 1 TDSJIT1 Jitter Analysis Application Compatibility The Jitter Analysis Application is compatible with the following Tektronix oscilloscopes m All TDS 500D and 700D Digital Phosphor Oscilloscopes with Option HD hard disk drive or Option 2M hard disk drive plus 8 MB record length m TDS 600C Digitizing Oscilloscopes with an Option HD hard disk drive m TDS 700C Color Digitizing Oscilloscopes serial number B020100 and up with Option HD hard disk drive or Option 2M hard disk drive plus 8 MB record length and with firmware version 5 2e and up TDSJIT1 Jitter Analysis Application User Manual 1 Product Description For a current list of compatible oscilloscopes check the Tektronix Inc web site http www tektronix com Measurement scopes index html in the Software and Drivers category Requirements and Restrictions The TDS Run Time Environment V1 1 and above must be installed on the oscilloscope to operate the Jitter Analysis Application The application does not support control by external GPIB comman
35. pear at the top of the display when you power on the oscilloscope If it does not appear contact your local Tektronix sales office After performing the power up self test the oscilloscope automatically begins the installation procedure As the application loads from the disk the oscilloscope displays a clock icon to indicate that it is busy Also the floppy disk drive LED is on indicating activity If the clock icon continues to display after the floppy disk LED has gone out a problem has occurred with the installation Repeat the above procedure If the problem persists contact your Tektronix representative When the installation is complete an Installation Complete message displays 3 Remove the floppy disk and cycle the power to the oscilloscope TDSJIT1 Jitter Analysis Application User Manual 3 Installation Updates Through a Web Browser If there is an update for this application it will be available from the Tektronix ftp site To install an application update you will need to download it from the ftp site to a hard disk copy it to a blank DOS formatted floppy disk and then install it on your oscilloscope NOTE More information about changes to the application or installation is in a Readme txt file on the ftp site You should read it before you continue To copy the application from a web browser follow these steps 1 Access the ftp site at ftp ftp tek com mbd support 00 index html 1 2 S
36. period of three 3 months from the date of shipment If a medium or encoding proves defective during the warranty period Tektronix will provide a replacement in exchange for the defective medium Except as to the media on which this software product is furnished this software product is provided as is without warranty of any kind either express or implied Tektronix does not warrant that the functions contained in this software product will meet Customer s requirements or that the operation of the programs will be uninterrupted or error free In order to obtain service under this warranty Customer must notify Tektronix of the defect before the expiration of the warranty period If Tektronix is unable to provide a replacement that is free from defects in materials and workmanship within a reasonable time thereafter Customer may terminate the license for this software product and return this software product and any associated materials for credit or refund THIS WARRANTY IS GIVEN BY TEKTRONIX IN LIEU OF ANY OTHER WARRANTIES EXPRESS OR IMPLIED TEKTRONIX AND ITS VENDORS DISCLAIM ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE TEKTRONIX RESPONSIBILITY TO REPLACE DEFECTIVE MEDIA OR REFUND CUSTOMER S PAYMENT IS THE SOLE AND EXCLUSIVE REMEDY PROVIDED TO THE CUSTOMER FOR BREACH OF THIS WARRANTY TEKTRONIX AND ITS VENDORS WILL NOT BE LIABLE FOR ANY INDIRECT SPECIAL INCIDENTAL OR CONSEQUENTIAL DAMAGES IRRESPECTIVE OF W
37. plication 5 measurement 7 Statistics readout 9 turning off 9 T tdsjitl ini file 23 technical support viii Tektronix contacting viii terms vii tutorial lessons 11 Cycle to Cycle measurement 12 Duty Cycle measurement 12 exiting the application 19 Frequency measurement 12 Histogram format 14 18 N Cycle measurement 12 Period measurement 12 Profile format 16 19 Pulse Width measurement 12 recalling a setup 20 saving a setup 19 Skew measurement 17 Statistics readout 13 18 TDSJIT1 Jitter Analysis Application User Manual Index V viewing obscured parts of the waveform 9 W Warning messages 34 TDSJIT1 Jitter Analysis Application User Manual warning messages 34 waveform viewing obscured portions 9 web site 2 43 Index 44 TDSJIT1 Jitter Analysis Application User Manual
38. r ee 11 Starting the Application oooooooooooororcrr ee 11 Loading the Reference Waveform File 00 ce cee eee eee eee 11 Taking Measurements from One Waveform 0 00 eee eee eee 12 Taking Measurements from Two Waveforms 0 eee eee eee 17 Saving a Setup and Exiting the Application 0 0 eee ee eee 19 Recalling Setup vais e do ae dt enden 20 Reference Menu Structure cece ccc cee cece rete eee hh 21 Setup Parameters srl I a eR EE See a EET 23 Saving and Recalling Setups 0 ce cece esee 23 Single Waveform Measurements 0 0c cee eee eee eee eens 24 Histogram Format Setup 0 e eect cence 26 Profile Format Setup 23 0048 oe eset aa ae 27 Duo Waveform Measurements seseeeeeeeee ee 29 Localizing Measurements 2 0 0 n 31 TDSJIT1 Jitter Analysis Application User Manual i Table of Contents Index Measurement Descriptions eee 33 Warning Messages 0 E ce ete e ene e eee 34 Oscilloscope Setup Guidelines 0 0 0 0 0 cece eee eee eee 34 Test Methodology 2 0 0c ec IIIA 34 Edge Time Measurements 00 cece eee eee tees 35 Period Measurement sss 35 Frequency Measurement sseseeeee eee ete 36 Cycle to Cycle Measurement lesse 36 N Cycle Measurement 00 eee eee cee eee tees 37 Pulse Width Measurement 0 0 0 eee eee
39. re starting the measurement If you select Single mode and want to take another measurement press Start side again TDSJIT1 Jitter Analysis Application User Manual 33 Measurement Descriptions Warning Messages All jitter measurements provide a warning if the input conditions do not support accurate measurements For example the Period measurement warns you if you do not have at least two cycle start edges in the acquired waveform Oscilloscope Setup Guidelines For all measurements use the following guidelines to set up the oscilloscope 1 Thesignal is any channel reference waveform or math waveform 2 The vertical scale for the waveform must be set so that the waveform does not exceed the vertical range of the TDS oscilloscope 3 When possible limit the bandwidth such as to 20 MHz and acquire data using the Hi Res mode This increases the accuracy of the measurement 4 The time per division must be set small enough to capture sufficient waveform detail and avoid aliasing 5 Longer record lengths increase measurement accuracy Test Methodology The application performs the measurement according to the following algorithm 1 Imports the current waveform 2 Checks that the voltage level plus or minus half the hysteresis are within the 2 5 to 97 5 range of the peak to peak waveform values 3 Checks that there are a minimum number of edges in the waveform to calculate the measurement as follows m Two cycle s
40. ress Level side and specify where on the slope to set the measurement threshold Press Hysteresis side and specify the margin above and below the threshold which the voltage must cross to be recognized as changing Press Done side 4 If you want to localize the measurement see Localizing Measurements on page 31 do so now The application defaults to the settings specified in the Trigger menu 5 Press Control main Start side to start the measurement 6 Wait for the measurement to complete and display the Statistics readout if enabled TDSJIT1 Jitter Analysis Application User Manual 35 Measurement Descriptions Frequency Measurement Definition Procedure The Frequency measurement calculates the inverse of the period for each cycle The Frequency measurement is calculated using the following equation F 1 P Where F is the frequency P is the period To set up the Frequency measurement follow these steps 1 Press Measure main Frequency side 2 To select the channel reference or math waveform to be measured press Frequency Setup main Input side 3 Follow steps 3 through 6 on page 35 Cycle to Cycle Measurement Definition Procedure 36 The Cycle to Cycle measurement calculates the difference in period measure ments from one cycle to the next The Cycle to Cycle measurement is calculated using the following equations AP Pro Ps Where AP is the di
41. sition mode The Single option performs measurements on a single acquisition and stops The Free Run option repeatedly acquires a waveform performs timing measurements and jitter analysis and arms the trigger 8 Press Start side NOTE Do not change oscilloscope settings while a measurement is being taken Doing so can invalidate the measurement Do not attempt to execute external GPIB commands to control the oscilloscope while running the application Doing so may interrupt the process To clear the results from the Statistics readout and graphical formats press Reset All side You do not have to wait for the measurement to complete to clear the results TDSJIT1 Jitter Analysis Application User Manual Functional Overview Viewing the Results Statistics Readout Histogram Graphical Format 9 You can press the Pause or Stop side menu buttons to interrupt or stop the measurement However the application will complete the measurement in progress before responding which can be several seconds for long records In Single mode when the measurements have successfully completed for a waveform segment the Statistics readout refreshes if enabled and graphical format information is saved in the selected reference waveforms 1f enabled Long waveforms may be processed in shorter segments The jitter analysis displays continue to update while processing the waveform The application provides information on the v
42. tart edges Period Frequency Pulse Width Duty Cycle m Three cycle start edges Cycle to Cycle m 2N 1 cycle start edges N Cycle m Two edges on each of two waveforms Skew 4 Performs the measurement 5 Uses the results in the Statistics readout or saves the results formatted graphically in a reference waveform 34 TDSJIT1 Jitter Analysis Application User Manual Measurement Descriptions Edge Time Measurements All timing measurements are based on the time locations of edges within each acquisition Edge conditions are defined in the setup menu of each timing measurement 7 represents the acquisition edge times where n is an index between 1 and the number of edges in the acquisition Period Measurement The Period measurement calculates the duration of a cycle as defined by a start and a stop edge The first start edge is called the initial edge Edges are defined by slope threshold and hysteresis Definition The Period measurement is calculated using one of the following equations P n T Ta Where P is the period measurement Procedure To set up the Period measurement follow these steps 1 Press Measure main gt Period side 2 To select the channel reference or math waveform to be measured press Period Setup main Input side 3 To specify where to start the measurement press Cycle Start Edge side Press Slope side and specify the edge on which to start the measurement Rising or Falling P
43. udes local help information about the measurements modes with some explanation of the individual controls To display the local help follow these steps 1 Press Utility main Help side 2 Usethe side menu buttons to navigate through the help Using Other Functions You can switch between the Jitter Analysis Application and other oscilloscope functions To access primary oscilloscope functions press the desired front panel control To return to the application push the SHIFT then the APPLICATION front panel menu buttons as shown in Figure 4 TDSJIT1 Jitter Analysis Application User Manual Functional Overview Push the SHIFT then the APPLICATION button to return to the application SAVE RECALL WAVEFORM APPLICATION MENU ACQUIRE MENU MEASURE CHARDCCSY RUN STOP SELECT UTILITY SHIFT CURSOR DISPLAY pur E ICO Figure 4 Returning to the application Taking a Measurement You can set up the application to take any one of a variety of measurements on one or on two waveforms To set up the application to take a jitter measurement follow these steps 1 2 TDSJIT1 Jitter Analysis Application User Manual Start the application as described on page 5 In the application Measure menu press the side menu button for the type of measurement you want to take To take measurements from a single waveform you can select Period Frequency Cycle to Cycle N Cycle Pulse Width
44. y Statistics lo n Off Input Profile Profile Height Setup Duty Cycle Polarity Value at E Cycle Start Edge Reset Profile Display Statistics Store Profile In Profile Length Mode Single F ree Run Control Start amp Continue Pause Stop Reset All Help Utility Exit Save Setup Recall Setup Default Setup Figure 16 Application menu structure TDSJIT1 Jitter Analysis Application User Manual 21 Menu Structure 22 TDSJIT1 Jitter Analysis Application User Manual SE M Setup Parameters This section describes the menus and menu items for the jitter measurements Saving and Recalling Setups You can save and recall application menu settings Figure 17 shows the Utility menu with the save and recall side menus Tek ERE 100kS s E utility Help Save setup Period Recall After all application menu a pme Setup parameters have been set as desired Chi 10 0m press Control Start to execute Ko ov peau l the measurement etup Measure Setup histogram Profile Control Period Feriod e Off Ready Figure 17 Save Setup and Recall Setup selections in the Utility menu The save recall function is controlled from the application Utility menu and contains the following selections m To store the current application settings press Utility main gt Save Setup side The HD0 APP TDSJIT1 TEMP TDSJIT1
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