Tektronix DPO77002SX, DPS77004SX, DPO75902SX, DPS75904SX, DPO75002SX Online Help

...

PAMJET

ransmitter Analysis Solution

Application Help

*P077120711*

077-1207-1

PAMJET

ransmitter Analysis Solution

Application Help

*P077120711*

077-1207-1

Copyright © Tektronix. All rights reserved. Licensed software products are owned by Tektronix or its subsidiaries or suppliers, and are protected by national copyright laws and international treaty provisions. T and pending. Information in this publication supersedes that in all previously published material. Specifications and price change privileges reserved.

TEKTRONIX and TEK are registered trademarks of Tektronix, Inc.

Tektronix, Inc.

14150 SW Karl Braun Drive

P.O. Box 500

Beaverton, OR 97077

USA

For product information, sales, service, and technical support:

• In North America, call 1-800-833-9200.

• Worldwide, visit www.tek.com to find contacts in your area.

ektronix products are covered by U.S. and foreign patents, issued

Table of Contents

List of Figures..............................................................................................................................................................................10

List of Tables................................................................................................................................................................................11

Welcome..................................................................................................................................................................................... 12

Getting started.............................................................................................................................................................................13

Getting started with PAMJET Transmitter Analysis solution................................................................................................ 13

Starting-Closing the application........................................................................................................................................... 13

Using the software...................................................................................................................................................................... 15

Main controls........................................................................................................................................................................15

Config: Save................................................................................................................................................................. 15

Config: Recall............................................................................................................................................................... 15

Config: Default.............................................................................................................................................................. 15

Clear............................................................................................................................................................................. 15

Recalc...........................................................................................................................................................................15

Single............................................................................................................................................................................15

Run............................................................................................................................................................................... 15

Stop.............................................................................................................................................................................. 15

Show Plots....................................................................................................................................................................16

Status Bar..................................................................................................................................................................... 16

Help.............................................................................................................................................................................. 16

Version..........................................................................................................................................................................16

Tabs..................................................................................................................................................................................... 16

Setup............................................................................................................................................................................ 16

Select............................................................................................................................................................................16

Full waveform................................................................................................................................................................16

Averaged waveform......................................................................................................................................................16

Rise fall......................................................................................................................................................................... 16

Reports......................................................................................................................................................................... 17

Log................................................................................................................................................................................17

Prefs............................................................................................................................................................................. 17

Setting up analysis parameters............................................................................................................................................17

Processing flow.............................................................................................................................................................17

Main setup.................................................................................................................................................................... 18

Clock recovery.............................................................................................................................................................. 19

Threshold setup............................................................................................................................................................ 19

Waveform filter..............................................................................................................................................................19

Receive filter................................................................................................................................................................. 20

CTLE, FFE and DFE ....................................................................................................................................................20

Selecting and configuring measurements............................................................................................................................24

Statistical eye analysis..................................................................................................................................................25

BER targets for jitter analysis........................................................................................................................................27

Measurement of SNDR (Signal to Noise and Distortion Ratio).....................................................................................27

Running an analysis.............................................................................................................................................................28

Viewing the results...............................................................................................................................................................29

Full waveform................................................................................................................................................................29

PAMJET Transmitter Analysis Solution Application Help 5

Table of Contents

Correlated waveform.....................................................................................................................................................30

Rise and fall times

........................................................................................................................................................ 30

PAMJET Plots window.........................................................................................................................................................31

Accumulated eye plot annotations................................................................................................................................32

Error Navigator window........................................................................................................................................................33

OIF-CEI jitter measurements: UUGJ, UBHPJ and Even-Odd Jitter ....................................................................................35

IEEE electrical measurements: J

IEEE electrical measurements: V PCIe Gen6 electrical measurements: T

SNDR(PCIe), RLM(PCIe), V

, J4u, J3u, J

rms

di(pk-pk)

TX-uTJ, TTX-RJ, TTX-uDJdd, TTX-UPW-TJ, TTX-UPW-DJDD,

TX-DIFF-PP, VTX-EIEOS

, J

3u03

, Even-Odd Jitter, Rise/Fall Time and SNR

4u04

, VMA, dvf and dR

....................................................................................................36

.................................................................................... 36

peak

............................36

ISI

JNu(PCIe), Jrms(PCIe),

PCIe Gen6 electrical measurements: Tx Preset Equalization............................................................................................. 37

Spread spectrum clocking measurements...........................................................................................................................37

Optical measurements......................................................................................................................................................... 38

IEEE optical measurements.................................................................................................................................................39

Saving results in a report..................................................................................................................................................... 40

Using the event log.............................................................................................................................................................. 44

Preferences..........................................................................................................................................................................45

Population control......................................................................................................................................................... 46

Halt on closed center eye............................................................................................................................................. 46

Error Navigator..............................................................................................................................................................46

Measurement logging................................................................................................................................................... 47

Display units................................................................................................................................................................. 47

Scope noise compensation...........................................................................................................................................47

Export pattern to a text file ...........................................................................................................................................48

Scope noise characterization...............................................................................................................................................48

Measuring scope noise for electrical signals................................................................................................................ 49

Measuring scope noise for optical signals.................................................................................................................... 51

Measurements............................................................................................................................................................................ 55

General full waveform measurements................................................................................................................................. 55

Measurements per level in the PAMJET eye.......................................................................................................................62

Measurements per eye opening (upper, middle, lower) in the PAMJET eye....................................................................... 62

Measurements for the correlated waveform ....................................................................................................................... 63

Measurements per level in the correlated PAMJET eye......................................................................................................64

Measurements for rise times and fall times......................................................................................................................... 64

GPIB command reference...........................................................................................................................................................65

Handshaking protocol.......................................................................................................................................................... 65

Best practice when programming using GPIB commands...................................................................................................65

GPIB commands..................................................................................................................................................................65

APPLICATION:ACTIVATE "PAM Analysis (PAMJET)"..................................................................................................65

VARIABLE:VALUE "pam4","version?".......................................................................................................................... 65

VARIABLE:VALUE "pam4","exit".................................................................................................................................. 66

VARIABLE:VALUE? "pam4"......................................................................................................................................... 66

VARIABLE:VALUE "pam4","clear"................................................................................................................................ 66

VARIABLE:VALUE "pam4","datasource [ch1|ch2|ch3|ch4|math1|ref1]".......................................................................66

VARIABLE:VALUE "pam4","default"............................................................................................................................. 66

VARIABLE:VALUE "pam4","lasterror?".........................................................................................................................67

VARIABLE:VALUE "pam4", "probetype <value>"......................................................................................................... 67

VARIABLE:VALUE "pam4","recalc" ............................................................................................................................. 67

Table of Contents

VARIABLE:VALUE "pam4","recall <filename>".............................................................................................................67

ARIABLE:VALUE "pam4","run"...................................................................................................................................67

VARIABLE:VALUE "pam4","state?" ............................................................................................................................. 67

VARIABLE:VALUE "pam4","saveconfig <filename>"....................................................................................................68

VARIABLE:VALUE "pam4","single"...............................................................................................................................68

VARIABLE:VALUE "pam4","savereport <filename>".................................................................................................... 68

VARIABLE:VALUE "pam4","meascategory [electrical|optical]".....................................................................................68

VARIABLE:VALUE "pam4", "technology [400GCK | PCIe Gen 6]”...............................................................................68

VARIABLE:VALUE "pam4","nominalsymbolrate <value>"............................................................................................69

VARIABLE:VALUE "pam4","nominalbitrate <value>"....................................................................................................69

VARIABLE:VALUE "pam4", "thresholdauto <value>"................................................................................................... 69

VARIABLE:VALUE "pam4", "thresholdhigh <value>"....................................................................................................70

VARIABLE:VALUE "pam4", "thresholdmid <value>".....................................................................................................70

VARIABLE:VALUE "pam4", "thresholdlow <value>".....................................................................................................70

VARIABLE:VALUE "pam4", "waveformfilteron <value>"...............................................................................................70

VARIABLE:VALUE "pam4", "loadfilter <filtername>".................................................................................................... 71

VARIABLE:VALUE "pam4", "ctleon <value>" ...............................................................................................................71

VARIABLE:VALUE "pam4", "ctletype <value>".............................................................................................................71

VARIABLE:VALUE "pam4", "ctledesign <value>".........................................................................................................72

VARIABLE:VALUE "pam4", "ctlepreset <value>"..........................................................................................................72

VARIABLE:VALUE "pam4", "ctleadc <value>"..............................................................................................................73

VARIABLE:VALUE "pam4", "ctlefp1 <value>"...............................................................................................................73

VARIABLE:VALUE "pam4", "ctlefp2 <value>"...............................................................................................................73

VARIABLE:VALUE "pam4", "ctlefp3 <value>"...............................................................................................................73

VARIABLE:VALUE "pam4", "ctlefz <value>".................................................................................................................74

VARIABLE:VALUE "pam4", "ctlefz2 <value>"...............................................................................................................74

VARIABLE:VALUE "pam4", "dfeon <value>"................................................................................................................ 74

VARIABLE:VALUE "pam4", "dfeadaptmode <value>".................................................................................................. 74

VARIABLE:VALUE "pam4", "dfenumtaps <value>"...................................................................................................... 75

VARIABLE:VALUE "pam4", "dfetapvalues <filename>"................................................................................................75

VARIABLE:VALUE "pam4", "ffeon <value>"................................................................................................................. 75

VARIABLE:VALUE "pam4", "ffeadaptmode <value>"................................................................................................... 76

VARIABLE:VALUE "pam4", "ffenumtaps <value>"....................................................................................................... 76

VARIABLE:VALUE "pam4", "ffereftap <value>"............................................................................................................76

VARIABLE:VALUE "pam4", "ffetapspersymbol <value>"..............................................................................................76

VARIABLE:VALUE "pam4", "ffetapvalues <filename>".................................................................................................77

VARIABLE:VALUE "pam4", "savelog <filename>"........................................................................................................77

VARIABLE:VALUE "pam4", "clearlog".......................................................................................................................... 77

VARIABLE:VALUE "pam4", "noiseanalysison <value>"................................................................................................77

VARIABLE:VALUE "pam4", "noiseber <value>"........................................................................................................... 78

VARIABLE:VALUE "pam4", "halteyeclosureon <value>"..............................................................................................78

VARIABLE:VALUE "pam4", "popcontrolmethod <value>"............................................................................................ 78

VARIABLE:VALUE "pam4", "popcontrolsymbols <value>"........................................................................................... 79

VARIABLE:VALUE "pam4", "popcontrolacquisitions <value>"......................................................................................79

VARIABLE:VALUE "pam4", "enablesavecsv <value>"................................................................................................. 79

VARIABLE:VALUE "pam4", "clockmethod <value>".....................................................................................................80

VARIABLE:VALUE "pam4", "clockmodel <value>"....................................................................................................... 80

VARIABLE:VALUE "pam4", "clockpllmodel <value>"....................................................................................................80

VARIABLE:VALUE "pam4", "clockplldamp <value>".................................................................................................... 80

PAMJET Transmitter Analysis Solution Application Help 7

Table of Contents

VARIABLE:VALUE "pam4", "clockpllbw <value>".........................................................................................................81

ARIABLE:VALUE "pam4", "clockjtfbw <value>"..........................................................................................................81

VARIABLE:VALUE "pam4", "results ceijittermeas?"..................................................................................................... 81

VARIABLE:VALUE "pam4", "results corrmeas?".......................................................................................................... 81

VARIABLE:VALUE "pam4", "results corrlevel1?"..........................................................................................................82

VARIABLE:VALUE "pam4", "results corrlevel2?"..........................................................................................................82

VARIABLE:VALUE "pam4", "results eyelow?".............................................................................................................. 82

VARIABLE:VALUE "pam4", "results eyemid?"..............................................................................................................82

VARIABLE:VALUE "pam4", "results eyeupp?"..............................................................................................................83

VARIABLE:VALUE "pam4", "results fall1?"...................................................................................................................83

VARIABLE:VALUE "pam4", "results fall2?"...................................................................................................................83

VARIABLE:VALUE "pam4", "results fullmeas?"............................................................................................................83

VARIABLE:VALUE "pam4", "results fullmeas1?"..........................................................................................................84

VARIABLE:VALUE "pam4", "results fullmeas2?"..........................................................................................................84

VARIABLE:VALUE "pam4", "results fulllevel1?"........................................................................................................... 84

VARIABLE:VALUE "pam4", "results fulllevel2?"........................................................................................................... 84

VARIABLE:VALUE "pam4","results hlowleft?".............................................................................................................. 85

VARIABLE:VALUE "pam4","results hlowright?"............................................................................................................85

VARIABLE:VALUE "pam4","results hmidleft?"..............................................................................................................85

VARIABLE:VALUE "pam4","results hmidright?"............................................................................................................85

VARIABLE:VALUE "pam4","results huppleft?"..............................................................................................................85

VARIABLE:VALUE "pam4","results huppright?"........................................................................................................... 85

VARIABLE:VALUE "pam4", "results ieeemeas?"..........................................................................................................86

VARIABLE:VALUE "pam4", "results opticalmeas?"...................................................................................................... 86

VARIABLE:VALUE "pam4", "eradjustison <value>"......................................................................................................86

VARIABLE:VALUE "pam4", "eradjust <value>"............................................................................................................ 86

VARIABLE:VALUE "pam4", "results rise1?"..................................................................................................................87

VARIABLE:VALUE "pam4", "results rise2?"..................................................................................................................87

VARIABLE:VALUE "pam4", "results sigmanperlevel?"................................................................................................. 87

VARIABLE:VALUE "pam4", "results sndrtp?"............................................................................................................... 87

VARIABLE:VALUE "pam4", "results sndrvoltage?".......................................................................................................87

VARIABLE:VALUE "pam4","results tmid?"....................................................................................................................88

VARIABLE:VALUE "pam4", "results tx preset equalization?"....................................................................................... 88

VARIABLE:VALUE "pam4", "scopenoisemvrms <value>"............................................................................................ 88

VARIABLE:VALUE "pam4", "sndron <value>".............................................................................................................. 88

VARIABLE:VALUE "pam4", "sndrsamplenumber <value>".......................................................................................... 89

VARIABLE:VALUE "pam4", "sndrfilterlength <value>"..................................................................................................89

VARIABLE:VALUE "pam4", "sndrdelay <value>"..........................................................................................................89

VARIABLE:VALUE "pam4", "sndrnb <value>".............................................................................................................. 89

VARIABLE:VALUE "pam4", "sndrbtfilteron <value>".................................................................................................... 90

VARIABLE:VALUE "pam4", "sndrdebugplotson <value>".............................................................................................90

VARIABLE:VALUE "pam4", "tx_preset <value>".......................................................................................................... 90

VARIABLE:VALUE "pam4", "errnavenabled <value>".................................................................................................. 90

VARIABLE:VALUE "pam4", "enablerelativeunit <value>".............................................................................................91

VARIABLE:VALUE "pam4","export <plot title>:<filename>"..........................................................................................91

VARIABLE:VALUE "pam4", "loggpibtraffic <value>".....................................................................................................91

VARIABLE:VALUE "pam4", "btfilteron <value>"........................................................................................................... 92

VARIABLE:VALUE "pam4", "btfilterbw <value>"...........................................................................................................92

VARIABLE:VALUE "pam4", "btfiltermode <value>"...................................................................................................... 92

Table of Contents

VARIABLE:VALUE "pam4", "rxfilteron <value>"........................................................................................................... 92

ARIABLE:VALUE "pam4", rxfilterbw<value>".............................................................................................................93

VARIABLE:VALUE "pam4", "rxfiltertype <value>".........................................................................................................93

VARIABLE:VALUE "pam4", "rxfiltermode <value>"...................................................................................................... 93

VARIABLE:VALUE "pam4", "symbolratemode <value>"...............................................................................................93

VARIABLE:VALUE "pam4", "dataratemode <value>"...................................................................................................94

VARIABLE:VALUE "pam4","exporterrors <filename>"..................................................................................................94

VARIABLE:VALUE "pam4","exportpatternon <value>".................................................................................................94

VARIABLE:VALUE "pam4","exportpattern <filename>"................................................................................................95

VARIABLE:VALUE "pam4","importpattern <filename>"................................................................................................95

VARIABLE:VALUE "pam4", "patterncontrol <value>"................................................................................................... 95

VARIABLE:VALUE "pam4", "patternstandard?"............................................................................................................95

VARIABLE:VALUE "pam4", "tdecqffetapnum <value>"................................................................................................ 96

VARIABLE:VALUE "pam4", "tdecqffetapui <value>".....................................................................................................96

VARIABLE:VALUE "pam4", "tdecqffeautoset <value>".................................................................................................96

VARIABLE:VALUE "pam4", "tdecqffetapvalues?".........................................................................................................96

VARIABLE:VALUE "pam4", "tdecqsamplesui <value>"................................................................................................ 97

VARIABLE:VALUE "pam4", "tdecqmaxprecursor <value>".......................................................................................... 97

VARIABLE:VALUE "pam4", "tdecqscopenoise <value>".............................................................................................. 97

VARIABLE:VALUE "pam4", "tdecqextendedsearch <value>".......................................................................................97

VARIABLE:VALUE "pam4", "tdecqverticaladjust <value>"........................................................................................... 98

VARIABLE:VALUE "pam4", "select <mnames>"...........................................................................................................98

VARIABLE:VALUE "pam4", "deselect <mnames>".......................................................................................................98

VARIABLE:VALUE "pam4", "isselect <mnames>"........................................................................................................98

VARIABLE:VALUE "pam4", "pcie_jitterber <value>".....................................................................................................99

VARIABLE:VALUE "pam4", "pcie_jitterdebugplotson <value>".................................................................................... 99

VARIABLE:VALUE "pam4", "pcie_sndron <value>"......................................................................................................99

VARIABLE:VALUE "pam4", "pcie_sndrsamplenumber <value>"..................................................................................99

VARIABLE:VALUE "pam4", " pcie_sndrfilterlength <value>"......................................................................................100

VARIABLE:VALUE "pam4", "pcie_sndrdelay <value>"...............................................................................................100

VARIABLE:VALUE "pam4", "pcie_sndrdebugplotson [1|0]"........................................................................................100

VARIABLE:VALUE "pam4", "isiresdp <value>"...........................................................................................................100

VARIABLE:VALUE "pam4", "isiresnp <value>"...........................................................................................................101

VARIABLE:VALUE "pam4", "weightedwindowtype <value>"......................................................................................101

VARIABLE:VALUE "pam4", "enablereferencereceiverieee802d3ck <value>"............................................................101

VARIABLE:VALUE "pam4", " fixtures4pfile<filename>"..............................................................................................101

Measurement names <mnames> tables.....................................................................................................................102

Sample GPIB script (Python 3.5)....................................................................................................................................... 105

Glossary.................................................................................................................................................................................... 109

PAMJET Transmitter Analysis Solution Application Help 9

List of Figures

Figure 1: CTLE Optimization Setup............................................................................................................................................ 61

List of Tables

Table 1: Electrical measurement names................................................................................................................................... 102

Table 2: Optical measurement names.......................................................................................................................................103

Table 3: PCIe measurement names..........................................................................................................................................104

Table 4: Additional 400GCK measurement names................................................................................................................... 105

PAMJET Transmitter Analysis Solution Application Help 11

Welcome

The PAMJET Transmitter Analysis software application enhances the capabilities of the DPO/DPS/MSO70000DX/SX series oscilloscopes (with 13 GHz or greater bandwidth), adding transmitter and channel testing for four-level Pulse Amplitude Modulation (PAM4) devices and interfaces for both electrical and optical physical domains.

The PAMJET application can run on the following Tektronix products:

DPO77002SX Oscilloscope

DPS77004SX Oscilloscope

DPO75902SX Oscilloscope

DPS75904SX Oscilloscope

DPO75002SX Oscilloscope

DPS75004SX Oscilloscope

DPO73304SX Oscilloscope

DPS73308SX Oscilloscope

DPO72504SX Oscilloscope

DPO72304SX Oscilloscope

DPO72004SX Oscilloscope

DPO71604SX Oscilloscope

DPO71304SX Oscilloscope

DPO73304DX Oscilloscope

DPO72504DX Oscilloscope

DPO72304DX Oscilloscope

DPO72004DX Oscilloscope

DPO71604DX Oscilloscope

MSO73304DX Oscilloscope

MSO72504DX Oscilloscope

MSO72304DX Oscilloscope

MSO72004DX Oscilloscope

MSO71604DX Oscilloscope

Getting started

Getting started with PAMJET Transmitter Analysis solution

The PAMJET Transmitter Analysis software application runs on the Tektronix performance oscilloscopes listed in the Preface. The application enables transmitter and channel testing for four-level Pulse Amplitude Modulation (PAM4) devices and interfaces, for both electrical and optical physical domains.

Optical testing is typically performed using the Tektronix DPO7OE1 or DPO7OE2 optical probe, although 3rd-party O/E converters may also be used. The electrical and optical capabilities are separately licensed, so some features described in this manual may be disabled depending on which licenses you have available. Trial licenses are separately available for the electrical and optical features.

Using filter files produced by the Serial Data Link Analysis (SDLA) application, the PAMJET Transmitter Analysis application allows you to de-embed probes or fixtures and embed a channel model. PAMJET Transmitter Analysis also allows you to apply several types of equalization from directly within the PAMJET application.

After any waveform processing is complete, PAMJET Transmitter Analysis uses the DPOJET application and additional resources to perform voltage and timing measurements and render eye diagrams on the target waveform. If the waveform contains a repeating pattern, the application additionally calculates the Correlated Waveform (which removes uncorrelated behavior such as random and periodic jitter/noise) and provides additional measurements on this waveform.

The key features of the PAMJET application are:

• Channel embedding and fixture de-embedding by way of .flt files

• Equalization (CTLE, FFE, and DFE, either individually or together)

• Configurable clock recovery

• Jitter measurements per eye for repeating patterns

• Eye diagrams for performance visualization

• BER eye contours for each eye along with IEEE and OIF-CEI-compliant eye measurements such as EW and EH

• IEEE and OIF-CEI-compliant jitter measurements such as J4u, J

• PCIe Gen 6 compliant jitter measurements such as T

• PCIe Gen 6 compliant transmitter voltage parameters such as Signal to Noise and Distortion Ratio (SNDR), Level Separation Mismatch Ratio (RLM), V

• Symbol error detection and navigation plus SER and BER measurements

• Transmitter characterization measurements: such as Signal to Noise and Distortion Ratio (SNDR) and TDECQ measurements

• Correlated waveform computation

• HTML-style report generation for presentation, sharing or archiving

• Programmable interface for test automation

• Automatic or manual voltage reference thresholds

• Measurement logging to .csv files

• Ck measurements like V

TX-DIFF-PP,

di(pk-pk)

and V

TX-EIEOS

, VMA, dvf, dR

TX-uTJ, TTX-RJ, TTX-uDJdd, TTX-UPW-TJ, TTX-UPW-DJDD,

, Gaussian window, Compute eye opening, Receive Filter, ISI

peak

, UUGJ, UBHPJ and even-odd jitter

rms

JNu(PCIe), and Jrms(PCIe)

RES

Starting-Closing the application

After you install the PAMJET software on your oscilloscope, start your oscilloscope application and wait for it to initialize. To launch the PAMJET application, select Analyze > PAM Analysis (PAMJET) from the oscilloscope menu, as shown in the following figure.

PAMJET Transmitter Analysis Solution Application Help 13

Getting started

The first time that the application is started after installation, it may take up to two minutes to appear. This is normal, and is due to one-time initialization.

o close the PAMJET application, click the red square in the upper right corner of the application window and then click "Yes" in the

verification dialog.

Using the software

This section describes the basic operation of the PAMJET Transmitter Analysis application.

Main controls

The following controls are on the main application panel and are accessible regardless of which tab is currently selected.

Config: Save

Select this button to display a dialog that allows you to save the current PAMJET Transmitter Analysis configuration in a proprietary binary file with the .psf extension.

Config: Recall

Select this button to recall a saved configuration file.

Config: Default

Select this button to restore all configuration settings to the values present when the application is first launched.

Clear

Selecting this button clears all accumulated measurement results. The results are also cleared when you change any configuration parameter.

Recalc

Selecting this button causes the application to perform a processing cycle on the waveform already present in scope memory. This allows you to change configuration parameters such as clock recovery or threshold and then re-run the analysis on the same waveform. For reference waveforms, Single and Recalc behave the same way.

Some measurements cannot produce a result until multiple waveforms have been processed, due to the sample size requirements of the measurement. Since Recalc can only re-analyze the waveform already in the oscilloscope memory, it cannot be used to re-compute these population-intensive measurements.

Single

Selecting this button causes the application to acquire a single waveform and perform a processing cycle, consisting of waveform filtering, equalization, clock recovery, and computation of measurements and eye diagrams. If the scope was in continuous acquisition (Run) mode, it is stopped so that the waveform that was analyzed remains on the screen and in acquisition memory.

Some measurements require a higher population of symbols than a single analysis cycle can obtain. In these cases, you can either select Single again or use Run mode.

Run

Selecting this button causes the PAMJET Application to repeatedly acquire waveforms and perform processing cycles as described for Single. The process continues until you press the Stop button or until a configured population limit has been met. For some measurements (e.g. EW, EH, J4u, J

measurements. For other measurements, results are re-computed for each new processing cycle.

, UUGJ and UBHPJ) the results must be accumulated across multiple cycles to build the population required by the

rms

Stop

The Stop button replaces the Single or Run button when processing is in progress. Selecting the Stop button interrupts processing.

PAMJET Transmitter Analysis Solution Application Help 15

Using the software

Show Plots

The Show Plots button is only visible when auxiliary plot windows are present, and is used to bring those windows to the foreground in case they have been minimized or are behind the main application window

Status Bar

The status bar is at the bottom of the screen. During analysis, the status bar reports the progress of the processing.

Help

Selecting the question mark button opens the PAMJET Transmitter Analysis Software User Manual (this document) in a separate window. The manual opens to the section that corresponds to the panel (tab) currently displayed.

Version

Click on About text in the status bar to display the software version of the application.

This is the same information that appears briefly when the application launches.

The version also appears in any HTML-style reports that are generated.

abs

Setup

Selecting the Setup tab opens the Setup screen, which allows you to set up the most commonly used analysis parameters, including which type of equalizer to use. See Setting up analysis parameters on page 17.

Select

Clicking the Select tab opens a screen where you can choose the measurement category (Electrical vs. Optical). If the electrical category is chosen, then you can choose "PCIe Gen 6" or "400GCK" technologies and then select specific measurements. It also allows you to configure the measurements.

See Selecting and configuring measurements on page 24.

Full waveform

Selecting the Full Wfm tab opens the Results for Full Waveform screen. This screen displays the measurement results for the full waveform. See Viewing the results on page 29.

Averaged waveform

Selecting the Avg. Wfm tab opens the Results for Correlated Waveform screen. This screen displays the measurement results for the correlated waveform. Results of averaged waveform are displayed only if Correlated Waveform Analysis measurement is chosen in the test tree. See Viewing the results on page 29.

Rise fall

Selecting the Rise/Fall tab opens the Rise Times and Fall Times screen. The maximum, minimum, and mean rise and fall times are displayed for all transitions in the correlated waveform, along with the number of times each transition type occurs. Results of Rise and fall measurements are displayed only if Rise/Fall measurement is chosen in the test tree. See Viewing the results on page 29.

Using the software

Reports

Selecting the Reports tab opens the Reports screen. This screen allows you to select a file name and save the analysis report.

Log

Selecting the Log tab provides a view of the activity log, which shows information such as when the analysis started and stopped, how many UI have been accumulated, and when data was saved. The log also captures warnings, error messages and other auxiliary information. See Using the event log on page 44.

Prefs

Selecting the Prefs tab allows you to adjust user preferences and some infrequently-used configuration items. See

Preferences on page

45.

Setting up analysis parameters

Use the Setup screen to set the most common analysis parameters.

Note: Configuration parameters should only be changed when the application is in the idle state.

Processing flow

In broad terms, the individual boxes on the Setup Panel represent processing blocks through which a chosen input signal flows prior to being measured. That processing flow can be better understood by reference to the following figure:

PAMJET Transmitter Analysis Solution Application Help 17

Using the software

The blue blocks in the flow diagram correspond to the blue boxes on the Setup panel, and all except the Clock Recovery block may be enabled or disabled. When you first launch the application, all the processing blocks are disabled so that the input signal, after clock recovery

The green blocks in the flow diagram correspond to measurements. Like the processing blocks, most of them can be enabled or disabled. The plots, represented by purple blocks, cannot be individually enabled but are tied to the measurements. (Some special-purpose plots are not shown in the diagram.)

, goes directly to the measurements and plots.

Note: The Correlated Eye and associated measurements, as well as the SNDR measurements, are always done prior to the FFE and DFE equalizers. For this reason, the Accumulated and Correlated eye diagrams may have a dif character when FFE or DFE equalization is enabled. Similarly, the TDECQ measurement includes its own FFE, so the TDECQ eye may have a different visual appearance.

ferent scale or visual

Main setup

Choose the P remaining Math and Ref sources may be used by the PAMJET application (depending on which features and options are being used), and may be overwritten by the PAMJET application without warning.

There are two modes for controlling data rate and pattern, Auto Detect and User-guided. In the default Auto Detect mode, the PAMJET application will automatically detect the data rate during analysis, in most cases. The detected rate always appears in the measurement results on the Full Wfm panel but it also appears in the Main Setup panel when Auto Detect is enabled, after clock recovery has finished.

In the User-guided mode, you enter an approximate data rate to guide the detection process in either Giga-symbols per second (GBaud) or GBits per second. Remember that since PAM4 signaling carries 2 bits per symbol, the symbol rate or baud rate is one half of the bit rate. For example, a bit rate of 51.2 Gbps corresponds to a symbol rate of 25.6 GBaud.

AMJET waveform source that you wish to analyze. The available sources are Ch1 - Ch4, Math1 and Ref1. Some or all of the

User-guided mode is particularly useful when the input waveform lacks cues about its true rate. For example, one PAM4 Linearity pattern consists of 16 consecutive repeats of each of 10 symbols. If it is running at 25 GBd, the waveform only has transitions every 640 ps even though one unit interval is 40 ps. This makes the signal appear to be a 10-symbol pattern at a symbol rate of 25 GBd/16, or 1.5625 GBd. Using User-guided mode and entering a symbol rate of 25 GBd will cause it to be correctly interpreted as a 160-symbol pattern. If the entered rate is within about 5% of the actual rate, the clock will be recovered and the actual rate will be displayed on the Full Wfm panel.

Using the software

Like the symbol rate, the data pattern can either be auto-detected (default) or user-directed. When it is user-directed the known symbol stream is imported by means of an ASCII text file. The file may contain symbols from any set of four numerical values that are equally spaced. Some common examples of symbol sets are:

{0, 1, 2, 3}

•

• {1, 2, 3, 4}

• {-1, -0.33, +0.33, +1}

If only two numerical values are represented in the text file, they will taken to match the two outer PAMJET symbols. A PRBS13Q text file is installed by default and you can use this as a model to create other pattern files as needed.

If user-guided symbol rate is used, the application will still perform automatic symbol detection. It will then auto-correlate the recovered symbols with the specified ones to determine the most likely pattern phase (timing offset). During this process it will also check whether the algebraic inverse of the given pattern provides a better fit to the waveform. If the inverted pattern is a better fit, this is noted in the message history on the Log tab.

In addition to importing a pattern to control analysis, you can export the automatically-detected pattern as an ASCII text file, either for every processing cycle or for the current waveform. Refer Preferences on page 45 for more details.

You can also export an ASCII file that shows all deviations from the expected pattern (whether that pattern was auto-detected or user-provided). See the export errors command in the GPIB Command Reference portion of this manual for more details.

Clock recovery

Clock recovery is performed using a noise-tolerant software model of a phase locked loop (PLL). You can choose a Type 1 or Type 2 loop (which in most contexts are equivalent to 1st and 2nd order loops, respectively). You can enter the bandwidth in Megahertz, and for Type 2

loops, the loop damping.

The bandwidth entered is the Jitter Transfer Function (JTF) bandwidth, which is the bandwidth of the high-pass filter function defining which jitter is NOT tracked by the clock recovery. For Type 1 loops, the JTF bandwidth is the same as the loop bandwidth. For Type 2 loops, the JTF and loop bandwidth are slightly different (by a factor that depends on the damping factor). For most standards, it is the JTF bandwidth that is specified.

You can also switch between the configurable PLL and fixed behavioral CDR methods. The behavioral clock recovery contains CDR models of transfer functions based on the standard requirements.

The collections available at this time are:

• PCIe Gen6 64G 0p7 (Nov 2021)

If you have enabled one or both equalizers, the clock recovery is applied after the CTLE and jointly with the FFE/DFE processing.

Threshold setup

The three thresholds nominally correspond to the centers, in the vertical dimension, of the three eyes in the PAMJET eye diagram. By default (Auto Detect), appropriate thresholds are picked based on analysis of symbol levels in the source waveform, and displayed both on the Config tab and on the Full Wfm results screen. To designate specific thresholds, unselect the Auto Detect checkbox and directly enter the desired thresholds using units of millivolts (electrical) or microwatts (optical).

Waveform filter

The Waveform Filter feature allows you to modify the source waveform by applying a FIR filter, using the oscilloscope Math system. Click the Waveform Filter checkbox to enable the feature and use the Browse button to select the desired filter file, which will have a .flt extension. See your oscilloscope documentation for more information on filter files.

One common use for waveform filters is to de-embed a probe or fixture, or to embed a reference channel. The SDLA application can be used to create or combine filters that can be applied using this feature.

PAMJET Transmitter Analysis Solution Application Help 19

Using the software

Receive filter

When the Receive filter checkbox is enabled, a filter based on the choices is applied to the source waveform after any waveform filter and before CTLE. This filter is required for several compliance measurements.

Note: Be careful not to apply the BT filter twice. For example, when using an optical probe, the probe often includes an Optical Reference Receiver (ORR), which has a Bessel-Thomson response. Be sure to disable the ORR in the probe. When working with

ektronix optical probes (e.g. DPO7OE1), the PAMJET application automatically sets the probe response to "Flat to maximum

T bandwidth" if the BT filter is enabled and the measurement category is set to "Optical".

The type of receive filter, order, filter's selection mode(auto/manual), and -3 dB bandwidth are displayed in the filter's setup panel when the filter configuration menu is closed. To adjust these parameters, press the Config button under the bandwidth to open the Receive Filter configuration window.

The receive filter can be configured to either “Bessel-Thomson” or “Butterworth”. The order of the filter is shown based on the choice made. In Auto Bandwidth mode, the P

• 0.5 of the actual symbol rate for Bessel-Thomson filter.

• 0.75 of the actual symbol rate for Butterworth filter.

In Manual Bandwidth mode, you can specify the precise -3 dB bandwidth. For every processing cycle during which the Receive Filter is enabled, the PAMJET application automatically exports the created filter in the format of a .flt file ("ReceiveFilter.flt") to C:\Users\<username>\Tektronix\TekApplications\PAMJET\Filters. One common use for this feature is to apply the filter file in scope MATH or other analysis packages to emulate the Receive filter.

The filter's selection mode and -3 dB bandwidth are displayed in the filter's setup panel when the filter configuration menu is closed. To adjust these parameters, press the Config button under the bandwidth to open the Bessel-Thomson Filter configuration window.

AMJET application automatically sets the filter's -3 dB bandwidth to

CTLE, FFE and DFE

Depending on the characteristics of the transmitter and signal channel, the PAMJET eye might be closed at the channel output. An equalizer can be used to open the eye back up. By checking the associated boxes in the Setup screen, one can model one or multiple of the following types of equalizers:

• Continuous-time linear equalizer (CTLE)

• Feed-forward equalizer (FFE)

• Decision-feedback equalizer (DFE)

Using the software

Set the equalizer parameters as desired for modeling the effects of the equalizer on your signal. Change the parameters and run the analysis again to see the ef

The CTLE model offers two types of operation. The first is Custom design, in which you can directly control individual poles and zeros. You can choose between a design with one zero and two poles (typical of first-generation standards) or a design with two zeros and three poles. Once the design is chosen, you can directly adjust each available parameter.

The other type of CTLE is one based on selectable aggregations of parameters, called Presets, which are usually specified by the standards bodies, and usually identified by the amount of de-emphasis such as '1 dB' or '3.5 dB'. For a given preset, you cannot change individual CTLE parameters but you can view the pole and zero frequencies that are in effect. First use the CTLE Type control to choose a collection of presets, and then use the Preset Name control to select a specific preset. The collections available at this time are:

• OIF-CEI Gen I: 2-pole/1-zero design per oif2014.230.06.pdf (Feb 2015)

• OIF-CEI Gen II: 3-pole/2-zero design per oif2014.230.10.pdf (Feb 2017)

• IEEE 802.3bs Draft 3.3: 3-pole/2-zero design with 17 presets (Jul 2017)

• IEEE 802.3bs Draft 3.5 (final): 3-pole/2-zero design with 17 presets (Oct 2017)

• PCIe Gen6 64G 0p7: 6-pole/3-zero design with 11 presets (Nov 2021)

• IEEE 802.3ck TP1a: 3-pole/2-zero design with 54 presets (June 2022)

• IEEE 802.3ck TP4 Far-end: 3-pole/2-zero design with 40 presets (June 2022)

• IEEE 802.3ck TP4 Near-end: 3-pole/2-zero design with 25 presets(June 2022)

• USB-Gen4 v2 Captive device: 1-pole 1-zero design with 10 presets (Oct 2021)

fects of various settings.

Don't forget to enable the checkbox at the top of the CTLE block; otherwise the CTLE model will not take effect. Similar to Bessel-Thomson filter, for every processing cycle during which the CTLE is enabled, the PAMJET application automatically exports the created filter. The filter is exported in the format of a .flt file ("CTLE.flt") to C:\Users\<username>\Tektronix\TekApplications\PAMJET\Filters.

Note: Although the CTLE poles are designated using numerical suf consistent across the various standards that use them). The equalizer operates exactly the same way regardless of the order in which the pole frequencies appear. Likewise, a CTLE with two zeros will behave exactly the same way independent of the order in which the two zero frequencies appear.

As with CTLE, FFE and DFE can be individually enabled or disabled by using their respective checkboxes.

fixes (e.g. Fp1 and Fp2), the order is not important (and is not

PAMJET Transmitter Analysis Solution Application Help 21

Using the software

FFE and DFE can be individually configured by clicking on “Edit FFE” and “Edit DFE”, which brings up a separate window for configuring each equalizer

The following options are available for FFE/DFE tap adaptation:

• Auto-adapt taps: The adaptation routine starts by identifying initial tap settings and adjusts them to optimize recovery of the data and clock.

• Use taps as specified: The equalizer uses the current tap values as input on the graphical user interface. Use the entered values without changes and adaptation.

• Adapt using LFPR 802.3ck method [License Dependent]: Calculates the tap values using the Linear Fit Pulse Response (LFPR) as defined by IEEE 802.3ck.

• Adapt using LFPR PCIe method [License Dependent]: Calculates the tap values using the Linear Fit Pulse Response (LFPR) as defined by PCI Express Base Spec Rev 6.0 .

Note: The LFPR DFE methods automatically set the number of DFE taps and apply constraints to be spec compliant. However constraints. Using any LFPR based DFE requires the pattern length to be at least 30.

, you can subsequently adjust the number of taps to be different from the spec definition which may violate the

Using the software

PAMJET Transmitter Analysis Solution Application Help 23

Using the software

Parameter name Parameter value limit

FFE Number of taps [0, 25]

Reference tap position

1. Cannot exceed number of taps

2. (Ref tap - 1) /T

integer

aps per UI must be an

Number of taps per UI

DFE Number of taps [0, 16]

1. [1, 10]

2. Cannot exceed number of taps

Selecting and configuring measurements

The Select screen allows you to:

Choose either the Electrical or Optical domain

•

• Select different Electrical technologies

• Select which specific measurements to perform

• Configure any necessary measurement options

The Measurement Category radio buttons let you choose whether to perform electrical or optical measurements. If technology licenses are available, a drop-down menu will appear in front of the Electrical radio button and will populate the measurements accordingly. These categories are separately licensed, so you may find that one category has been pre-selected. If only one technology license is available, it will always remain selected.

Using the software

Below the radio buttons, a hierarchical selection tree allows you to choose measurements either individually or by groups. Selecting only the measurements you need can speed processing, and can also reduce clutter in the results screens and reports that you save.

o select an individual measurement, click the checkbox to the left of the measurement name. To select an entire group, click the

T corresponding group's box. If the group already contains a mix of selected and unselected measurements, a first click will de-select all, and the second will select all.

When you select or de-select a measurement or click directly on the measurement name, a new panel may appear to the right of the selection tree showing any configuration parameters for the highlighted measurement. If that measurement has no specific parameters, the right side of the screen will be blank. In many cases a configuration panel will be applicable to an entire group, in which case it only needs to be set for one measurement and will apply across the group.

For descriptions of the individual measurements, see Measurements on page 55. For descriptions of configuration panels that apply to specific measurement groups, see Statistical eye analysis on page 25, BER targets for jitter analysis on page 27, and Measurement of

SNDR (Signal to Noise and Distortion Ratio) on page 27.

Statistical eye analysis

Several PAM standards employ eye analysis that monitors both horizontal and vertical eye closure on a prescribed population of symbols. Since PAM interfaces typically have low noise margin and use coding (such as Forward Error Correction or FEC) to attain higher reliability, the performance goal for the physical layer bit error rate (BER) is usually 1e-5 to 1e-6. The applicable standards rely on direct acquisition of sufficient population for direct measurement rather than extrapolating eye closure from a smaller population. Example measurements based on this technique are EW6, EH6 and VEC, and the standards also define intermediate values (Hupp, Vupp, Hmid, Vmid, Hlow, Vlow) that are used to calculate the prescribed measurements. An analytical benefit of this approach is that BER eye contours are available that can give insight into eye closure at all timing phases and reference levels simultaneously.

Enable Statistical Eye Analysis : This checkbox turns the Statistical eye analysis feature on (default) or off. The measurement system behaves slightly differently depending on whether the feature is on, as defined here:

• Statistical Eye Analysis Off: All eye diagrams are rendered by the DPOJET application and automatically imported into the PAMJET Transmitter Analysis application. On the Full Wfm results panel, the last two columns in the eye measurement table display Eye Width and Eye Height. The EW6, EH6 and VEC measurements are displayed as N/A.

PAMJET Transmitter Analysis Solution Application Help 25

Using the software

• Statistical Eye Analysis On: A second plot window, titled PAMJET Plots, is created as analysis proceeds, and is used to accumulate annotated eye diagrams that show the width and height measurement locations. In this mode, the eye diagrams are rendered directly

AMJET application rather than being imported from DPOJET. On the Full Wfm results panel, the last two columns in the

by the P eye measurement table change to H_eye and V_eye. The EW6, EH6 and VEC measurements as well as the H_eye and V_eye measurements are only shown if an adequate symbol population has been accumulated; otherwise a footnote to the tables indicates that more population is needed. The table below shows how the H_eye and V_eye results shown in the eye measurement table map to the values {Hupp - Vlow} prescribed by CEI-56G-VSR-PAMJET (oif2014.230 draft 7, dated 10-June-2016):

Row H_eye V_eye

Upper Hupp Vupp

Middle Hmid Vmid

Lower Hlow Vlow

Statistical Eye Analysis BER Target: This statistical level determines what BER contour line will be drawn in the three P contour lines are, in turn, used to determine the EW, EH and VEC measurement values. For OIF-CEI compliance, the target must be 1e-6. If it is changed to a different value (say, 1e-5) then the EW6 and EH6 measurements on the Full Wfm panel change correspondingly (in this example, to EW5 and EH5). Since these measurements rely on direct measurement rather than extrapolation, changing the BER target will also change the population of symbols that must be acquired in order to make the measurement. The required population is 4 * 1/(BER Target), so for the default target of 1e-6, a population of 4e6 (or 1e6 in each of the four symbol levels) is needed. (The application will actually make the measurement if at least 95% of this population is acquired.) Eye diagrams retain their information across processing cycles unless cleared, so if the number of symbols is insufficient, you can click "Single" again to build greater population (assuming you have a live signal).

AM4 eyes. The

Additional configurations

Option to Enable Reference Receiver: When this checkbox is enabled, the noise due to reference receiver as defined in the IEEE 802.3

Annex 120G.5 is considered. The computation is dependent on the CTLE and Receive Filter configurations in the Setup menu <add the reference>.

eighting Window Type:

This determines the type of windowing technique to be applied to the vertical probability density functions (PDF) around the eye center.

• None: Consider only the vertical PDF at the eye center. No weighting.

Using the software

• Rectangular: The vertical PDFs around the eye center are weighted uniformly

• Gaussian: The vertical PDFs around the eye center are weighted using a gaussian function as defined in the IEEE 802.3 Annex 120G.5.

Weighting Window Width (±UI):

This determines the number of vertical PDFs to be considered around the eye center. The number is the amount of Unit Interval (UI) that needs to be considered. For example, a value of “0.05” conveys that about 0.05 (or 5%) of the Unit Interval from the left of eye center and to the right of the eye center should be considered for the weighted window. The value is configurable from 0.01 (1%) till 0.1 (10%) of the Unit Interval (UI) in steps of 0.005 (0.5%).

BER targets for jitter analysis

These three BER Target values correspond to the three TJ@BER columns in the central results table on the Full Wfm panel. For example, when a value of -12 is entered on the Prefs panel (corresponding to a BER target value of 1e-12 or one expected error for every 1 x 10

bits), the corresponding column heading in the results table changes to TJ@-12. This shorthand for the more conventional TJ@1E-12 is due to space constraints.

These targets are used for conventional jitter analysis and eye width extrapolation, and should not be confused with the Statistical Eye Analysis BER Target.

Measurement of SNDR (Signal to Noise and Distortion Ratio)

Signal to Noise and Distortion Ratio is defined as the ratio in dB between the square of the linear fit pulse peak and the sum of squares of linear fit error ( σ e ) and vertical noise ( σ n ).

For standards compliance it should be measured on the pattern prescribed by the applicable standard, although other repeating patterns are acceptable if the pattern length is no longer than 10000.

In addition to reporting the SNDR value in dB, the component values p provided. All measurement values appear in the upper left (scrollable) table on the Full Wfm results tab.

Samples per Symbol (M): This determines the granularity with which the individual symbols in the waveform are analyzed. It has no connection with the number of oscilloscope samples per symbol. The valid range is 32 ≤ M ≤ 200, with a default of 32.

Linear Pulse Length (Np): This determines the number of symbols included in the linear fit analysis, and should be long enough to capture most of the energy in the pulse response. The valid range is 2 ≤ Np ≤ 10000, with a default value of 14.

Linear Pulse Delay (Dp): This determines the duration, in symbols, of the part of the pulse response that is assumed to occur prior to the main pulse. Its typical value is 2, to allow for some pre-shoot, but the valid range is 2 ≤ Dp ≤ Np-2.

Show Detail Plots: When this checkbox is enabled, the following auxiliary plots are created in a separate plot window, for additional insight into non-essential aspects of the measurement:

• Linear fit error, overlaid with one cycle of the averaged waveform.

• High and low symbol positions at which the noise measurements are taken within the averaged waveform.

(These plots are not saved in Report files.)

Whenever the SNDR measurement or any of its subcomponents are enabled, the linear fit pulse response is shown graphically in the main PAMJET Plots window, similar to the following image:

, σe and as well as the

max

σn value for each individual PAM level are

PAMJET Transmitter Analysis Solution Application Help 27

Using the software

The optional detail plots, when enabled, typically appear as follows:

Note: SNDR(PCIe) is majorly identical to the regular SNDR measurement and will report the same values. It only dif configurable parameters (M, Np, Dp) and in the computation of SigmaN. The default values of M, Np, and Dp for SNDR(PCIe) are 32, 600, and 4 respectively.

fers by the

Running an analysis

1. Set the signal path parameters on the Setup screen and verify that the options on the Prefs screen are as desired.

2. Click the Run, Single, or Recalc button to perform the analysis.

3. If the mode is Run or Single and the source directly or indirectly uses live channels (Ch1 - Ch4), a new waveform is acquired into

the oscilloscope waveform memory trigger occurs within about 10 seconds, the application changes to an edge trigger on the chosen source waveform.

If the waveform filter is enabled, the PAMJET application applies the filter and places the result in Math 4 on the oscilloscope. If one or more of the three forms of equalization is enabled, the output of the equalizer(s) is placed in Ref4. A synthesized clock waveform representing the recovered clock is placed in Ref3. If any measurement under the Statistical Eye Analysis category is enabled,

. Initially the application uses the trigger settings that have been configured on the scope, but if no

Using the software

the PAMJET application renders an eye diagram of the complete waveform at high resolution, accumulating the diagram with prior acquisitions to build population. If the waveform contains at least three full cycles of a repeating pattern, the P calculates one repeat of the correlated waveform and places it in Ref2. Finally, the PAMJET application sets up the appropriate measurements in DPOJET using either Math4, Ref4 or the original source waveform as the measurement source.

4. If correlated waveform analysis is possible, the PAMJET application creates the correlated waveform eye diagram and measurement values.

5. The PAMJET application finishes the current cycle by performing selected measurements based on the Select tab. For example, some jitter (RJ/DJ/TJ) measurements require DPOJET sequencing. When that is the case, the measurements and plots are imported from DPOJET for display in the PAMJET user interface. If no Statistical Eye Analysis measurements are enabled, DPOJET is also used to render the eye diagram.

6. If the mode is Run, steps 3 through 5 are repeated, until any population limits have been satisfied. A closed center eye may optionally be configured to halt Run mode.

7. The PAMJET application turns off the recovered clock waveform (Ref3) when processing completes, to avoid obscuring other waveforms on the oscilloscope screen. You can turn it back on from the oscilloscope File menu, if you want to view the recovered clock.

AMJET application

Viewing the results

To view measurement results open the following tabs.

Full waveform

Selecting the Full Wfm tab displays the Results for Full Waveform screen, which includes the Accumulated Eye diagram. Values for selected measurements are displayed above the eye diagram.

Note: Many measurements appear in the upper left table, and can be viewed by using that table's scroll bar

PAMJET Transmitter Analysis Solution Application Help 29

Using the software

The eye diagram is updated at the completion of each acquisition cycle.

Correlated waveform

Selecting the A jitter and noise have been removed. Values for time, amplitude, standard deviation, level, and time deviation are displayed above the eye diagram.

These results are displayed only if Correlated Waveform Analysis measurement is selected in the measurement tree.

vg. Wfm tab displays the Results for Correlated Waveform screen, which includes an eye diagram from which uncorrelated

Rise and fall times

Selecting the Rise/Fall tab displays the Rise T rise times and fall times for each of the six transition types in the PAMJET eye diagram, as well as the population (count) for each transition type.

The graphics beside each group of results help explain which transition is represented by that group, and the legend in the lower right corner of the screen explains which results fields correspond to the max (maximum), mean, min (minimum) and count.

The rise and fall time measurements are made on the correlated waveform, because the deterministic waveform behavior (ISI) is usually of more interest than effects that may be due to instantaneous noise or jitter.

Rise and fall time measurement results are displayed only if Rise/Fall measurement is selected in the measurement tree.

The rise and fall times are measured between the 20% and 80% levels for the corresponding transition.

• If one or more transitions in the correlated waveform fail to reach one of the thresholds within the symbol period, then both the Mean and Max rise or fall time will remain blank, and only the Min time (corresponding to the fastest edge) will be displayed.

• If there are no transitions between a specific pair of symbol levels (which can happen depending on the symbol pattern), then all three statistics for that transition will remain blank and the corresponding count will be zero.

The sum of the populations for the 12 transition types may be equal to the waveform's pattern length, but it will usually be less. This is because no transition occurs when two adjacent symbols are alike (e.g. 0→0, 1→1, 2→2 or 3→3).

imes and Fall Times screen. Selecting the tab displays the maximum, minimum, and mean

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Tektronix DPO77002SX, DPS77004SX, DPO75902SX, DPS75904SX, DPO75002SX Online Help

Specifications and Main Features

Frequently Asked Questions

User Manual

Table of Contents

List of Figures

List of Tables

Welcome

Getting started

Getting started with PAMJET Transmitter Analysis solution

Starting-Closing the application

Using the software

Main controls

Config: Save

Config: Recall

Config: Default

Clear

Recalc

Single

Stop

Show Plots

Status Bar

Help

Version

Setup

Select

Full waveform

Averaged waveform

Rise fall

Reports

Prefs

Setting up analysis parameters

Processing flow

Main setup

Clock recovery

Threshold setup

Waveform filter

Receive filter

CTLE, FFE and DFE

Selecting and configuring measurements

Statistical eye analysis

BER targets for jitter analysis

Measurement of SNDR (Signal to Noise and Distortion Ratio)

Running an analysis

Viewing the results

Full waveform

Correlated waveform

Rise and fall times