Tektronix IConnect,MeasureXtractor Primary User

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IConnect® and MeasureXtractor™ Signal Integrity, TDR, and S-parameter Analysis Software

ZZZ

Quick Start User Manual

*P071267701*

071-2677-01

IConnect® and MeasureXtractor™ Signal Integrity, TDR, and S-parameter Analysis Software

ZZZ

Quick Start User Manual

www.tektronix.com

071-2677-01

tional copyright laws and international treaty provisions.

Tektronix pro previously published material. Speciﬁcations and price change privileges reserved.

TEKTRONIX and TEK are registered trademarks of Tektronix, Inc.

IConnect is a registered trademark of Tektronix, Inc.

MeasureXtractor is a trademark of Tektronix, Inc.

ducts are covered by U.S. and foreign patents, issued and pending. Information in this publication supersedes that in all

Contacting Tektronix

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.tektronix.com to ﬁnd contacts in your area.

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 period of three (3) months from the date of shipment. If any such 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 s ervice 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 WITH RESPECT TO THE PRODUCT 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 WHETHER TEKTRONIX OR THE VENDO R HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES.

[W9b – 15AUG04]

Compliance Information ............................................................................................................... ii

Environment

Preface................................................................................................................................. iii

KeyFeatures ..................................................................................................................... iii

Documentat

Conventions Used in This Manual.... . . . . .... . . . . .... . . . . ..... . . . ..... . . . ...... . . ...... . . ...... . . . ..... . . . .... . . . . ..... . . . ..... . iv

Installation.............................................................................................................................. 1

IConnect S

Minimum System Requirements.... . . . . ..... . . . ..... . . . ..... . . ...... . . . ..... . . ...... . . .... . . . . .... . . . ...... . . . ..... . . . ..... . . ... 1

Installing Software................................................................................................................ 1

Starting a

Running IConnect on a Tektronix Oscilloscope . ...... . . ...... . . . ..... . . . .... . . . . ..... . . . ..... . . . ...... . . ...... . . ...... . . . ..... . 2

Running IConnect on a PC .... . . .... . . . . ..... . . . ..... . . . ..... . . .... . . . . ..... . . . ..... . . ...... . . . ..... . . .... . . . . ..... . . . ..... . . ... 3

Operatin

Application Examples................................................................................................................. 24

Index

g Basics ...................................................................................................................... 5

TheUser Interface ............................................................................................................... 5

Connecting the DUT . . .... . . . . .... . . . . ...... . . ...... . . . ..... . . . .... . . . . .... . . . . .... . . . . ..... . . . ...... . . . ..... . . . .... . . . . ..... . . . 10

Measure

Displaying the Correct TDR Waveform......................................................................................... 13

Acquiring, Saving, and Loading Waveforms . . . .... . . . . .... . . . . ..... . . . ..... . . . .... . . . . ..... . . . ..... . . . .... . . . . ..... . . . ..... . . . 18

File Op

Waveform Math ................................................................................................................. 23

Eye Dia

EZ Z-Line DUTTesting.......................................................................................................... 32

Automatically Creating S-Parameter Files (S-Parameter Wizard) ............................................................ 38

Manua

True Impedance Proﬁle (Z-Line) Measurement................................................................................ 42

Standard Modeling . . . ..... . . . .... . . . . ..... . . . ..... . . . ...... . . ...... . . ...... . . . ..... . . . .... . . . . ..... . . . ..... . . . ...... . . ...... . . .. 43

Adva

al Considerations................................................................................................... ii

ion................................................................................................................... iii

oftware Versions ..................................................................................................... 1

nd Stopping the Application.. . . . . .... . . . . ..... . . . ..... . . . ...... . . ...... . . ...... . . . ..... . . . .... . . . . ..... . . . ..... . . . .... 2

ment Best Practices ................................................................................................... 12

erations.................................................................................................................. 22

gram Compliance Testing .............................................................................................. 24

llyCreating S-Parameter Files .......................................................................................... 39

nced Modeling (MeasureXtractor™). . . ..... . . .... . . . . ..... . . . ..... . . .... . . . . .... . . . .... . . . . .... . . . .... . . . . ..... . . . ..... . . 49

Table of Content

IConnect® and MeasureXtractor™ Quick Start User Manual i

Compliance Info

rmation

Compliance In

This section lists the environmental standards with which the instrument complies.

formation

Environmental Considerations

This section provides information about the environmental impact of the product.

Product End-of-Life Handling

Observe the following guidelines when recycling an instrument or component:

Equipment

resources. The equipment may contain substances that could be harmful to the environment or human health if improperly handled at the product’s end of life. To avoid release of such substances into the environment and to reduce the use of natural r materials are reused or recycled appropriately.

Recycling.

esources, we encourage you to recycle this product in an appropriate system that will ensure that most of the

This symb to Directives 2002/96/EC and 2006/66/EC on waste electrical and electronic equipment (WEEE) and batteries. For information about recycling options, check the Support/Service section of the Tektronix Web site (ww

Production of this equipment (the hardware key) required the extraction and use of natural

ol indicates that this product complies with the applicable European Union requirements according

w.tektronix.com).

ii IConnect® and MeasureXtractor™ Quick Start User Manual

Preface

IConnect® and MeasureXtractor™ is TDR (time domain reﬂectometry) software that provides high-speed interconnect characterization. It is an integrated tool for measurement, compliance testing, modeling and validation for interconnects in printed and ﬂexible circuit boards, packages, ATE sockets, connectors, cables, and cable assemblies. IConnect provides accurate measurements and equivalent circuit models that predict reﬂections, ringing, and crosstalk in interconnects.

This software supports signal acquisition from the following instruments:

Tektronix: DSA8300 (recommended), DSA8200, CSA8000, CSA8000B, CSA8200, TDS8000, TDS8000B, and TDS8200

Key F eatures

Optimized for use with the Tektronix DSA8300 Digital Serial Analyzer sampling oscilloscope with 80E10, 80E08 and 80E04 true differential TDR modules

Single-click solution for PCI Express, Serial ATA, and HDMI manufacturing and standard compliance testing (including eye mask te

Preface

sts)

Analyze i

Perform i

Model PCB

Generat

Convert

Obtain S your TDR oscilloscope

Simple calibration procedure minimizes human errors and makes ﬁxture de-embedding a simple task

Obtain more accurate impedance measurements (Z-Line)

Automate manufacturing test and R&D measurements with scripts and programmatic control command line interface

nterconnect jitter, losses, crosstalk, reﬂections, and ringing concurrently in time and frequency domains

nterconnect link analysis to verify system level simulation accuracy

e Eye Diagrams with optional aggressors, periodic jitter insertion, and random jitter and noise insertion

TDR/T data into SPICE with MeasureXtractor; model passivity, stability, and causality guaranteed

-parameters (differential, single ended, mixed-mode; insertion, return loss, frequency domain crosstalk) using

Documentation

This manual provides installation, basic operation, and application example instructions for the IConnect® and MeasureXtractor™ TDR Software. For more detailed information, see the online help (Help > Help Contents).

s, ﬂexboards, connectors, cables, packages, and sockets

IConnect® and MeasureXtractor™ Quick Start User Manual iii

Preface

Conventions Used in This Manual

The following icon is used in this manual:

Sequence Step

iv IConnect® and MeasureXtractor™ Quick Start User Manual

Installation

IConnect Software Versions

IConnect is available in the following versions:

IConnect Evaluation: A free and fully functional evaluation version with a limited number of uses and limited time window of operation

IConnect and MeasureXtractor: Includes all application features (MeasureXtractor, modeling, S-parameters, Z-Line, Eye Diagram Viewer, standards compliance testing and more)

IConnect w/o MeasureXtractor: Includes all application features except MeasureXtractor

IConnect S-Parameters and Z-Line: Provides S-parameter and Z-Line functions

MinimumSystemRequirements

Microsoft Windows 7 Ultimate (32- and 64-bit) or XP on supported Tektronix oscilloscopes or a PC

TekVISA software (to run the S-parameter Wizard tool or to communicate with an oscilloscope over a local area network (LAN)

Installation

National Instruments GPIB board or a USB to GPIB adaptor (not required when running IConnect on supported Tektronix

scopes or over a LAN connection from a Windows PC to a supported Tektronix oscilloscope)

oscillo

l 1024 x 768 resolution monitor when running on any Tektronix sampling oscilloscope other than the DSA8300

Externa

Installing Software

IConnect Software

See the installation instructions that came with the IConnect software CD (071-2676-XX). You can download this ﬁle from the Tektronix Web site (www.tek.com/manuals).

ISA Software

TekV

If you plan to run IConnect on a PC and acquire waveforms from an oscilloscope connected to a LAN, or run the S-parameter Wizard function (on the oscilloscope or remotely from a PC), you must install TekVISA software on your PC.

NOTE. TekVISA is already installed on Tektronix DSA8300 oscilloscopes. Legacy Tektronix sampling oscilloscopes

(DSA8200 series and earlier) will need to have the speciﬁed version of TekVISA installed to correctly operate with this release of IConnect.

1. Check which version of TekVISA is installed on your oscilloscope and PC (open the TekVISA tool and click Help > About). If the version is earlier than 3.3.4.6, go to the Tektronix Web site (www.tektronix.com/software), search for tekvisa, and download version 3.3.4.6.

2. Follow the installation instructions provided with the TekVISA download ﬁle.

IConnect® and MeasureXtractor™ Quick Start User Manual 1

Installation

Starting and Stopping the Application

1. Before starti

hardware key into the appropriate USB or parallel port on your computer. If you already ha connected to your parallel port, plug the IConnect hardware key into the parallel port, and plu the back of the IConnect hardware key.

2. Click Start > Programs Tektronix Applications > IConnect and MeasureXt MeasureXtractor to start IConnect:

3. To stop IConnect, click File > Exit or the

window Close button. If you have any unsaved v to save the views before closing.

ng IConnect, plug the

ve a peripheral device

g the peripheral device into

ractor > IConnect and

iewers, IConnect prompts you

Runni

NOTE. If

close those applications.

you open other applications from within IConnect, such as the S-Parameter Wizard, closing IConnect does not

ng IConnect on a Tektronix Oscilloscope

You can install and run IConnect on a supported Tektronix oscilloscope. Running IConnect on an oscilloscope makes it unnecessary to use a separate PC with a GPIB card, keeping your benchtop area less cluttered.

To most effectively run IConnect on legacy Tektronix sampling oscilloscopes (models earlier than the DSA8300), connect an external 1024 x 768 resolution monitor to the oscilloscope. The external monitor lets you view all of the IConnect user interface, while the instrument display shows the application software. See your oscilloscope documentation for help on setting up dual monitor support.

NOTE. You do not need theTekVISA software to run IConnect on a separate PC that is connected to an oscilloscope directly

through a GPIB interface card. However, you do need TekVISA to remotely operate IConnect over a local area network or to run the S-parameter Wizard.

2 IConnect® and MeasureXtractor™ Quick Start User Manual

RunningIConnectonaPC

You can install and run IConnect on a PC and communicate with an oscilloscope using a GPIB card installed on the PC, a USB/GPIB adapter, or a LAN connection.

LAN Interface

Installation

Use the foll area network (LAN):

NOTE. You must install TekVISA on your PC, and both the instrument and the PC must have a working connection to the

LAN, before

The following instructions are written for TekVISA version 3.3.4.6. You can download TekVISA from the Tektronix Web site.

1. On the oscilloscope, click the VXI-11 server icon in the system tray and selectStart VXI-11 Server to enable the

2. On the oscilloscope desktop, right-click the My Comp uter icon and select Properties.ClicktheComputer Name tab

3. On the PC, right-click the TekVISA icon in the system tray and select Instrument Manager.

4. Click Search Criteria and click the Local LAN bar in the Search Criteria tool.

5. Click the Search Remote LAN check box and enter the oscilloscope computer name to the Add LAN Search Location

6. Click Search for Selected and click Done to close the applet. T he instrument you just added should be listed in the

7. Select the instrument you just added in this list and click Properties.

8. Enter GPIB8::1::INSTR intheDeviceNameﬁeld type and click OK.

owing steps to set up communications between IConnect on a PC and an oscilloscope connected to a local

doing this procedure.

VXI-11 server.

and write down the full name of the oscilloscope computer.

ﬁeld (from step 2). Click the down arrow to add this name to the search list.

Instruments ﬁeld on the main TekVISA Instrument Manager page.

NOTE. This is the default Tektronix oscilloscope GPIB address. If the oscilloscope GPIB address was changed from

the default, enter the correct oscilloscope GPIB address.

9. Start IConnect on the PC. Click the Waveform Acquisition toolbar button and select Te

Local. This should connect IConnect to the speciﬁed instrument.

NOTE. The VXI-11 LAN connection also provides a mechanism w ith which to send GPIB commands from a PC to a

Tektronix oscilloscope. This virtual GPIB connection works as well as a real (phy

sical GPIB card and cable) GPIB connection.

ktronix DSA/TDS/CSA8xxx

GPIB Card Interface

Install any VISA drivers that are required by the GPIB controller board installed in the PC.

Check the index number of the GPIB board installed in the PC that is running IConnect. If the GPIB board index number is not GPIB0, change the default IConnect GPIB board setting to match that of the GPIB board. (See page 18, Acquiring, Saving, and Loading Waveforms.)

IConnect® and MeasureXtractor™ Quick Start User Manual 3

Installation

Set the oscilloscope to online mode. If the oscilloscope is not in the online mode (is set to local mode), the oscilloscope ignores comman mode.

Set or verify that the oscilloscope is in talk/listen mode to enable two-way communication between the oscilloscope and the GPIB controller.

Set the IConnect GPIB address to match that of the oscilloscope. (See page 18, Acquiring, Saving, and Loading Waveforms.) controllers. IConnect has default values of 1 for Tektronix instruments. Change this value in IConnect to match your GPIB and equipment conﬁguration.

ds transmitted over the GPIB bus. See the oscilloscope user manual for details on setting the online

Any address between 0 and 31 is valid, although 0 is discouraged it is the default address of most GPIB

USBtoGPIBA

A USB to GPIB adapter enables a PC to communicate with a GPIB device. Follow the installation and operation instructions that came with the USB to GPIB adapter. The adapter must support the IEEE 488.2 speciﬁcation. The USB to GPIB interface should be transparent, with IConnect communicating with the oscilloscope using normal GPIB commands.

dapters

4 IConnect® and MeasureXtractor™ Quick Start User Manual

Operating Basic

Operating Bas

The User Interface

1. Menu Bar.

2. Toolbar. (See page 5, The Toolbar.)

3. Waveform/Data Views. (See page 6,

The Waveform/Data Views.)

4. Cursor View. (See page 9, Cursors and

Cursor Read

5. Status Bar.

Bar.)

6. Task Tabs. (See page 9, The Task Tabs.)

outs.)

(See page 10, The Status

ics

The Toolbar

The Toolbar provides one-click access to common operations. Click View > Toolbars and select the toolbar elements to

displa

The Standard toolbar buttons control common application operations including opening a new view or model window, open or save a ﬁle, cut

py tasks, print, and undo.

and co

xiliary toolbar buttons provide the following functions:

The Au

Opens task tabs with which you can acquire or load waveforms

Performs speciﬁc measurements or computations

Captures screen images to a ﬁle, clipboard, or printer

The Algorithm toolbar buttons. The S and Z buttons provide fast access to parameters and actions to compute S-parameter and Z-Line measurements.

IConnect® and MeasureXtractor™ Quick Start User Manual 5

Operating Basic

The Enhanced Accuracy toolbar buttons. The EAC1button runs the Enhanced Accuracy Characterization command (on DSA8200 oscilloscope

s) for improved long-record accuracy.

NOTE. The DSA8300 acquisition hardware does not require the IConnect

EAC function.

The Compensate Oscilloscope2button runs the temperature compensation function of the oscilloscope for improved long record waveform me

asurement accuracy. (See page 12, Measurement Best

Practices.)

The S-parameter Wizard button provides a graphical interface and procedure guidance to automatically acquire TDR and TDT waveforms from a DUT c

onnected to a Tektronix sampling oscilloscope to calculate and generate S-parameter and Touchstone ﬁles. (See page 38, Automatically Creating S-Parameter Files (S-Parameter Wizard).)

The Viewers toolbar buttons. The Eye Diagram button opens the Eye Diagram viewer for setting up and displaying Eye Diagrams. The EZ

pens the EZ Z-Line viewer for creating and comparing Z-Line

button o measurements against a known DUT reference.

The Model toolbar buttons open model viewers to extract a variety of interconnect models from measurement data for use in design simulation

idation. (See page 49, Advanced Modeling (MeasureXtractor™).)

and val

IConnect checks the oscilloscope thermal compensation status when you run the EAC function. If the oscilloscope or any module is not compensated, IConnect initiates the oscilloscope compensation program, and then runs the oscilloscope EAC program. If the oscilloscope and all modules are compensated, IConnect just runs the oscilloscope EAC program.

The Compensate Oscilloscope button runs the compensation program regardless of the current compensation status of the oscilloscope.

The Wa

veform/Data Views

The Waveform/Data views show acquired and calculated waveform and data traces

list of the waveforms in the viewer.

and a The type of waveform trace or data shown depends on the selected operation. If there

ultiple views available, each view is

are m accessed with a separate tab.

The icons to the left of the ﬁle names identify

waveform type:

the

oltage

V:V

Impedance

S-parameter

Unknown

6 IConnect® and MeasureXtractor™ Quick Start User Manual

Operating Basic

Waveform trace operations. A waveform trace is a plot of a measurement waveform or a data waveform calculated

by IConnect bas waveform trace:

Operation Description

Select a waveform Click a waveform to select it. You can also select a waveform by c licking on the

Move a wavef

Save a new wa waveform to a new name and/or location

Export waveform data to a different format

Delete a waveform from the view Right-click a selected waveform and select Delete. You can also select a

Show or the selected waveform

Create a label to associate with a

ﬁc waveform

speci

Hide a waveform Right-click a selected waveform and select Hide to remove the waveform from

Reset a waveform position Right-click a selected waveform and select Reset Position to reset the waveform

ign one DUT waveform with another

Al DUT waveform (EZ Z-Line function)

Apply a predeﬁned low pass ﬁlter and

ecalculate a waveform

isplay a waveform in a Spectrum

D view

Change the color and other properties of a waveform

Convert a S-Parameter waveform to an impedance versus frequency waveform

ed on measurement waveforms. The following table lists the operations that you can do on a selected

waveform name in the Legend tab for that view. Selecting a waveform sets the

ow the vertical scale and units of the selected waveform.

ag a waveform to move it.

k a selected waveform and select Save As. Navigate to where you want

e ﬁle, enter a new ﬁle name if required, and select the type of ﬁle to

to restore deleted waveforms.

click a selected waveform and select Cursor Readout. A check mark

orm name. Click and drag a label to move it. Right-click on a label to edit

aveform view (the waveform remains in the Legend list). The application

orm

veform or an existing

remove a cursor readout for

display to sh

Click and dr

Right-clic to save the ﬁle, and enter a new ﬁle name if required.

Right-click a selected waveform and select Export. Navigate to where you want to save th save to. Available export formats depend on the selected waveform.

waveform and press the keyboard Delete key. Use the Undo buttononthe Toolbar

Rightindicates that the cursor readouts are enabled for the selected waveform. Select Cursor Readout again to remove the cursor readout.

Right-click a selected waveform and select Label to create a default label with the wavef the label text, size, color, and other properties. A label does not move when you move its associated waveform.

the w can still access hidden waveforms to perform calculations. To restore a hidden waveform, right-click the waveform in the Legend list and select Unhide.

ts original position when acquired.

to i

ght-click a selected waveform and select Adjust to Position.TheAdjustto

Ri Position feature lets you align one DUT TDR waveform plot with another DUT plot to provide a more accurate comparison of their Z-Line plots.

Right-click a selected waveform and select Filter (n). The value of n is set in the

omputation tab, with the compute type set to Filter Waveform.

ight-click a selected waveform and select S pectrum .

Right-click a selected waveform and select Properties to change the waveform color, add comment text, hide or unhide the waveform, or enable or disable cursor readouts.

Right-click a reﬂected waveform and select Impedance. IConnect opens a new FD Waveform Viewer showing the impedance versus frequency plot.

NOTE. You should only do a S-Parameter to impedance versus frequency

conversion on reﬂection (return loss) S-Parameter waveforms. Reﬂection waveforms are typically named S11, S22, S33, and so on. Doing a conversion on a nonreﬂection waveform generates invalid results.

IConnect® and MeasureXtractor™ Quick Start User Manual 7

Operating Basic

Waveform view operations. Waveform View operations apply to the entire waveform plot area, and are accessible by

right-clickin you can do to the waveform view:

Operation Description

Zoom in on a speciﬁc region of the view

Set the horizontal and vertical scales to sh (Autoscale)

Undo zoom op waveform trace as deﬁned by the current scaling, whether set manually or by Autos

Set the ho for the waveform view

Create a label to save with the waveform view

Import view

Change the waveform plot units Right-click in a waveform view and select Plot. Select the type of plot and set

Expor Touchstone format ﬁle

g inside a waveform view when no waveform traces are selected. The following table lists the operations that

Click and drag in a view to zoom in on that region.

Right-click in a waveform view and select Autoscale.

ow all w aveform traces

erations to see the

cale

rizontal and vertical scales

waveform or other data into a

t the waveform view data to a

Right-click in a waveform view and select Zoom to 100%.

ick in a waveform view and select Set Scale. Enter the horizontal and

Right-cl vertical limits of the graph.

Right-click in the waveform view, select Label, and enter the label text. Click and drag a label to move it. Right-click on a label to edit the label text, size, color, and othe

Rightimport, then navigate to and select the ﬁle to import.

other parameters as needed. The available plot types depend on the waveform view (

Right the port type. Navigate to where you want to save the Touchstone ﬁle and enter a new ﬁle name if required. The available ﬁle options (based on the port numbers) depe

r properties.

click in a waveform view and select Import. Select the type of data to

waveform traces or spectrum view).

-click in the waveform view and select Export > Touchstone, and specify

nd on the number of the S-parameter waveforms.

8 IConnect® and MeasureXtractor™ Quick Start User Manual

The Task Tabs

The task tabs provide access to parameters and actions fo setting measurement parameters. Click the Auxiliary or Algorithm toolbar buttons to open associated Ta

Click a tab to show the parameters for that tab. Task tab contents change depending on the selected

You can undock a task tab from the main window by clicking and dragging on the double-lin move that tab away form the main application window.

r acquiring waveforms or

sk tabs.

measurement or operation.

e area at the top of the tabs to

Operating Basic

Cursors and Cursor Readouts

Cursors provide a way to take measurements at a speciﬁc point on a waveform. The cursor readouts s how the w aveform values at the cursor position.

1. Click and drag a cursor to m ove it. The

two vertical cursors (colored red and blue) let you take measurements at two points on one or more waveforms.

You can also use the keyboard arrow keys to move a waveform, and Ctrl+ the arrow keys for ﬁne movements.

2. Look at the Cursor readouts to see the

horizontal and vertical values at the cursor positions for each waveform and the difference (delta) value between the cursors for each waveform. The measurement units depend on the View plot type.

3. To enable a cursor readout for a

waveform, right-click a waveform and select Cursor Readout. (See page 7, Waveform trace operations.)

IConnect® and MeasureXtractor™ Quick Start User Manual 9

Operating Basic

The Status Bar

The Status Bar current operation and displays help text associated with the button, ﬁeld, or area at the current mo

Rolling the cursor over an interface element displays a pop-up description of that item, and more deta bar.

shows the status of the

use cursor position.

iled information in the Status

Connecting the DUT

Follow the connect the test cables, test ﬁxture (if used) and DUT to the oscilloscope. Use electrostatic handling precautions when initially connecting and while taking TDR measurements, as the TDR measurement modules are extremely susceptible to electros

Typical Measurement Setups

1-Port Single-Ended

procedures in your oscilloscope manual (and any associated TDR module or probe manuals) to correctly

tatic damage. Follow the oscilloscope procedures to deskew the test cables for accurate TDR/T measurements.

t Single-Ended

2-Por

10 IConnect® and MeasureXtractor™ Quick Start User Manual

4-Port Single-Ended

1-Port Differential

Operating Basic

2-Port D

NOTE. In the 4-Port Single-Ended mode, Full Thru calibration improves the phase accuracy on the crosstalk measurements

by measuring a Thru reference for each of the six TDT paths, in both directions. This creates twelve reference thru waveforms in all.

ifferential

Making good connections to the device under test.

CAUTION. Circuitry in the sampling module i s very susceptible to damage from electrostatic discharge or from overdrive

nals. To prevent electrostatic damage to the main instrument and sampling modules, follow the precautions described

sig in the manuals accompanying your oscilloscope. Be sure to only operate the sampling module in a static-controlled environment. Be sure to discharge the center and outer connectors of cables to ground before attaching the cable to

e sampling module.

Good connections to the DUT are critical to achieve high quality measurements. Using high-quality, low-loss microwave grade cables and probes enable the oscilloscope to deliver full incident rise time to the DUT. Since the minimum discontinuity that

an be resolved by a TDR step must be separated from the discontinuity next to it by about one-half the observed rise time,

c delivering a faster rise time to the DUT lets IConnect resolve smaller DUT sizes or achieve higher measurement resolution.

IConnect® and MeasureXtractor™ Quick Start User Manual 11

Operating Basic

Use the following guidelines when connecting the DUT to cables, probes, and/or a ﬁxture:

Use high-quality, low-loss microwave grade cables or probes. Generic cables such as RG-58 are rather stiff and the delay (theref

ore phase) varies considerably when the cable is ﬂexed.

Make sure that Allow the connector to dry completely before using.

Use a torque wrench on connections.

When using a barrel, use the correct wrench to hold the barrel while tightening the connectors.

Use high-quality reference standards. For best insertion loss accuracy, use a Thru reference. For best return loss accuracy, use an Open or Short, with a Load reference.

When the DUT requires a ﬁxture, make sure that the ﬁxture has a low-inductance, low-resistance ground return path to the oscillo

module connectors are clean. Clean connectors with a swab m oistened with isopropyl alcohol if needed.

scope to provide the cleanest measurement interface.

Measurement Best Practices

Taking accurate measurements is the most important element in measurement-based modeling. Without accurate measurements, skilled modeling and thorough veriﬁcation are a waste of time. T he following tips will help you to take accurate measurements.

Warm Up the Oscilloscope

ATimeDo and precision of the instrument, allow the instrument to warm up for 20-30 minutes before performing any measurements, to allow its temperature to stabilize. The oscilloscope manual may provide exact speciﬁcations on warm-up times for your pa during measurement sessions.

main Reﬂectometry (TDR) oscilloscope is a high-performance, high-accuracy instrument. To fully use the accuracy

rticular instrument. You should also keep the air temperature of the instrument environment as stable as possible

Compensate the Oscilloscope

Compensation optimizes the capability of the instrument to make accurate measurements at the ambient temperature. Click the Compensate Oscilloscope button to run the compensation program on supported Tektronix oscilloscopes. To run compensation on other oscilloscope models, see the oscilloscope user documentation.

Enhanced Accuracy Measurements

Enhanced Accuracy is a function on supported Tektronix oscilloscopes that improves measurement accuracy of long record length acquisitions. Click the EAC button to run the EAC program on supported Tektronix oscilloscopes (DSA8200 Series

h serial number B030000 and above, or DSA8200 Series with the DSA82EFEUP (Electrical Front End board) upgrade).

wit

NOTE. The D SA8300 acquisition hardware does not require the IConnect Enhanced Accuracy (EAC) mode.

12 IConnect® and MeasureXtractor™ Quick Start User Manual

Operating Basic

Observe Electrostatic Discharge Prevention Guidelines

Circuitry in the sampling module is very susceptible to damage from electrostatic discharge or from overdrive signals. To prevent electrostatic damage to the main instrument and sampling modules, follow the precautions described in the manuals accompanying your oscilloscope. Be sure to only operate the sampling module in a static-controlled environment. Be sure to discharge the center and outer connectors of cables to ground before attaching the cable to the sampling module.

Deskew the Oscilloscope Channels and Test Cables

Deskew the channels in the TDR oscilloscope when taking differential measurements (for coupled models). Follow your oscillosco

pe deskewing procedure before acquiring differential data.

Use Signal Averaging

Use signal averaging with the oscilloscope to reduce noise. 128 averages can provide an extra 20 dB of dynamic range.

Display the Correct TDR Waveform Information

To take useful TDR measurements for model extraction in IConnect, it is necessary to remove the incident transition from the displayed TDR waveform. (See page 13, Displaying the Correct TDR Waveform.)

Captur

Capture all the transitions in the reﬂection or transmission waveform that characterize the DUT. In many cases this includes the low-frequency asymptote, which means that the waveform must settle to an appropriate level:

If the measurement window stops before the waveform has settled, the resulting measurements and modeling may be inaccurate. For more information on TDR-based interconnect modeling and basics of TDR, download the IConnect TDR Software Modeling Quick Guide from the Tektronix Web site.

e an Adequate Length Waveform Data Record

To 0 V for short termination

To the full incident step amplitude for an open termination

To exactly half the incident step amplitude for a matched, or 50 Ω termination

Displaying the Correct TDR Waveform

IConnect requires just the reﬂected part of the TDR waveform for making measurements. Adjust the oscilloscope to remove the incident waveform step from the displayed waveform. There are two ways to remove the incident step; use the Autoset TDR function on supported Tektronix oscilloscopes, or manually set the waveform display to remove the incident step.

Auto Setup of TDR Waveforms (Tektronix 8000 Series Sampling Oscilloscopes)

Prerequisites:

Let the oscilloscope warm up at least 20 minutes, or until it has passed its warm-up compensation test, before taking measurements.

(Optional) To achieve maximum measurement accuracy, after instrument warm-up, click the Com pensation button to open the Compensation dialog box and execute compensation on the mainframe and TDR modules.

IConnect® and MeasureXtractor™ Quick Start User Manual 13

Operating Basic

1. Connect cables and ﬁxtures to the

oscilloscope using safe antistatic handling prac DUT.

2. On the oscilloscope, press the Setup Dialogs butt

tices. Do not connect the

on.

3. Click the TDR

4. In the Preset settings, click the channels

to use for your TDR measurements. For Differential measurements, click the Diff button for each pair of channels used.

5. In the TDR Step settings, enable measurement channels and set the step pulse polarity.

6. In the ACQ settings, enable measurement channels and set the units to V for each channel taking a TDR measurement.

tab.

7. Click the Advanced TDR Setup button (TDR Autoset Properties button for legacy oscilloscopes).

14 IConnect® and MeasureXtractor™ Quick Start User Manual

8. (DSA8300) Set the TDR Step Rate,

10 MHz Reference source, and Autoset Options ﬁelds

as shown in the Autoset

Properties dialog box. Click Close.

(DSA8200 and other legacy oscilloscopes) Set the Mode, Options, and TDR Options ﬁelds as shown in the Autoset Properties dialog box. Click Close.

Operating Basic

9. Press the Autoset front panel button to

and display the TDR waveform.

acquire

IConnect® and MeasureXtractor™ Quick Start User Manual 15

Operating Basic

10. Use the Horizontal POSITION knob to move the waveform to near the left edge of the screen.

11. Right-click t select Left to move it to the left side of the screen.

12. Connect the DUT to the text ﬁ xture.

13. Make sure that the DUT reﬂection step

is on screen.

14. The waveform record length should be two to three times as long as the distance from the l eft screen edge to the DUT reﬂection step, to accurately capture the required data. Use the Horizontal SCALE knob to set this if necessary.

You are now ready for IConnect to acquire waveforms from the oscilloscope.

he Reference icon and

16 IConnect® and MeasureXtractor™ Quick Start User Manual

Manual Setup of TDR Waveforms

Operating Basic

1. Connect cable

oscilloscope using safe antistatic handling practices. Do not connect the DUT.

2. Set the oscilloscope to take TDR

measurements. Adjust the oscilloscope to display b steps of the TDR waveform.

3. Adjust the oscilloscope to position the

incident step off-screen and the reﬂection step waveform edge near the left edge of the screen.

s and ﬁxtures to the

oth the incident and reﬂection

4. Position the Reference marker to just

left of the rising edge of the waveform.

5. Connect the DUT.

IConnect® and MeasureXtractor™ Quick Start User Manual 17

Operating Basic

6. Ensure that the DUT reﬂection step is on screen. Use the Horizontal SCALE knob to adjust this

if necessary.

7. The waveform r two to three times as long as the distance from the left screen edge to the DUT reﬂection st the required data. Use the Horizontal

SCALE knob to adjust this if necessary.

8. Repeat steps 6 and 7 until the waveform

is correct.

Yo u are now readyfor IConnect toacquire waveforms from the oscilloscope.

ecord length should be

ep, to accurately capture

Acquiring, Saving, and Loading Waveforms

Acquire and Save Waveforms from an Oscilloscope

Use this procedure to acquire waveforms from a connected instrument.

Set the oscilloscope to take the appropriate TDR or TDT measurements before acquiring waveforms i n IConnect. (See page 13, Displaying the Correct TDR Waveform.) Make sure to acquire all necessary waveforms for the IConnect

rement without changing the timebase on the oscilloscope.

measu

NOTE. If you are taking S-parameter measurements on a Tektronix CSA8200, use the S-parameter Wizard to set up

and acquire the measurements. The S-parameter Wizard automates the waveform setup and acquisition process,

ng signiﬁcant time and reducing measurement inaccuracies. (See page 38, Automatically Creating S-Parameter

savi Files (S-Parameter Wizard).)

18 IConnect® and MeasureXtractor™ Quick Start User Manual

1. Set the oscilloscope to display the

correct TDR waveform. (See page 13,

Displaying th

2. In IConnect, click the Waveform

Acquisitio

e Correct TDR Waveform.)

n button.

Operating Basic

3. Click the M

4. Select the appropriate instrument from

the Instrument list. If you get a “Could not all sets up the GPIB connection to the oscilloscope.

5. If the oscilloscope is being accessed

using Settings tab and verify or set the GPIB parameters, including the GPIB board inde

easure tab.

ocate” message, the next step

a GPIB card, click the Instrument

6. Sele

7. Cli

IConnect® and MeasureXtractor™ Quick Start User Manual 19

ct the waveforms or traces to acquire from the instrument. The displayed values depend on the selected

illoscope.

osc

ck the Measure tab and select the

waveform(s) or traces to acquire. Use standard Microsoft Windows operations

select multiple waveforms.

Operating Basic

8. If you are using a Tektronix instrument

with long record length capability, you can set the Use and click the Long Record Parameters button to set the long record length parameters f

Make sure to increase the Timeout value when using long records. Long record lengths are u long transmission lines.

9. (Optional) Click the EA Characterize

button to manually run enhanced measureme on supported Tektronix oscilloscopes. EAC improves long record length measureme function checks the oscilloscope compensation status. If the oscilloscope or any mod IConnect runs the oscilloscope compensation program before running EAC.

Long Record check box

or the acquired signal.

seful when working with

nt accuracy characterization

nt accuracy. The EAC

ules are not compensated,

10. Click th

11. To save a waveform to a ﬁle, right-click

e Acquire button. IConnect

opens the TD Waveform Viewer window and displays the acquired waveforms. You can model the DUT.

The Acquire function also checks the statu temperature compensation. If the oscilloscope is compensated (modules and ma function (on supported oscilloscopes) and acquires the waveforms. If the osci IConnect displays a dialog box asking if you want to compensate the oscilloscope befo to compensate the oscilloscope before acquiring waveforms.

as Legend list and select Save. Navigate to where you want to save the ﬁle, and en

now use IConnect to analyze or

s of the Tektronix oscilloscope

inframe), IConnect runs the EAC

lloscope is not compensated,

re acquiring waveforms. Click Yes

elected waveform in the viewer or

ter a ﬁle name.

20 IConnect® and MeasureXtractor™ Quick Start User Manual

Load Waveforms from Saved Files

Use this procedure to load waveforms that were saved during a previous waveform acquisition session.

1. Select File > Open. Navigate to and

select the ﬁle or ﬁles to open. Click

Open.

2. IConnect loads the waveforms and

displays the correct viewer for the waveforms.

Operating Basic

Using Drag-and-Drop to Load Waveforms or Files

n use standard Microsoft Windows drag-and-drop operations to load waveform, model, and waveform viewer ﬁles

You ca into IConnect. As you will need adequate room on a display to view both the Windows Explorer and IConnect application window, this method is recommended only when running IConnect on a PC, or when running IConnect on a Tektronix

loscope to which an external monitor is connected.

oscil

IConnect® and MeasureXtractor™ Quick Start User Manual 21

Operating Basic

File Operations

File Operation Procedure

Save a single waveform Select the waveform in the plot or Legend tab l ist. Right-click to open the shortcut

Save one or mo location

Export a wa ﬁle

Export a w ﬁle

Save the oscilloscope settings to a ﬁle Click File > Save Instrument Settings. Use normal Windows operations to

Load (restore) oscilloscope settings from a ﬁ

veform to a CSV format

aveform to a Touchstone

re waveforms to a new

menu and clic

Select the wa shortcut menu and click Save As. IConnect sequentially opens a Save As dialog box, one for each selected waveform. Use normal Windows operations to specify the locatio

Select the menu and click Export. Select CSV. Use normal Windows operations to specify the location and name for the saved waveform. Select the type of CSV ﬁle (space, co

Right-click in the plot to open the shortcut menu and select Export > Touchstone. Use norma waveform. You can only export waveforms to Touchstone that are appropriate for that format.

specify a naming convention to clearly label the ﬁle with the oscilloscope to which the settings apply.

Click File > Load Instrument Settings. Use normal Windows operations to locate settings to the connected oscilloscope.

k Save.

veform(s) in the plot or Legend tab list. Right-click to open the

n and name for the saved waveform.

waveform in the plot or Legend tab list. Right-click to open the shortcut

mma, or tab-delimited).

l Windows operations to specify the location and name for the saved

the location and name for the oscilloscope settings ﬁle. You should use

and select the appropriate oscilloscope settings ﬁle. Click OK to load the

Execute oscilloscope commands from a ﬁle

NOTE. Loading a settings ﬁle saved from one oscilloscope into a different type

illoscope will not work, and may cause unpredictable results on the target

of osc oscilloscope.

You can use a text ﬁle to send valid GPIB commands to the instrument. Create atextﬁle that contains the correct GPIB commands and syntax for the target

lloscope. Click File > Load Instrument Settings. Use normal Windows

osci operations to locate and select the appropriate oscilloscope command ﬁle. Click OK to send the commands to the connected oscilloscope.

E. If the oscilloscope does not respond as expected, and the

NOT

communications to the oscilloscope are good, verify that the GPIB command syntax and values are correct in the command text ﬁle.

22 IConnect® and MeasureXtractor™ Quick Start User Manual

Waveform Math

In general, it is better to let the oscilloscope perform waveform math, as the oscilloscope can usually do this math faster. IConnect can do addition, subtraction, multiplication, and division of two w aveforms. It can also do integration, differentiation, and ﬁltering of a waveform. Since a constant may be substituted for one of the waveforms, waveform math also allows convenient scaling and offsetting of waveforms.

Waveform math is executed from the computation window by choosing Waveform Math from the Compute list box. Select the required operator from the Operator drop-down list located in the Waveforms group. Depending on the nature of the operator, select either one or two operand waveforms in the remaining drop-down list boxes in the group. Click the Compute button, and the resultant waveform is placed in the selected waveform viewer. To use a constant as one of your operands, select Constant from one of the waveform selection boxes, and enter the value of the constant in the ﬁeld at the bottom of the Computation window.

Integration and Differentiation

Integration is performed as the running sum of the waveform data points, multiplied by the time step between data points. For this reason, the magnitude of the integrated waveform will typically be several orders of magnitude smaller than that of

nal waveform. Differentiation is performed as the difference between consecutive waveform data points, divided by

the origi the time step between data points. For this reason, the magnitude of the differentiated waveform will typically be several orders of magnitude larger than that of the original waveform.

Operating Basic

NOTE. Di

uncommon for high-frequency noise to be visibly present in a differentiated waveform.

fferentiation attenuates low-frequency components and ampliﬁes high-frequency components. Therefore, it is not

IConnect® and MeasureXtractor™ Quick Start User Manual 23

Application Exa

mples

Application Examples

Eye Diagram Compliance Testing

A compliance test consists of a series of Eye Diagram tests (eye setups) as deﬁned for a standard such as SATA, HDMI, or PCI Express. Each standard deﬁnes the number of Eye Diagram tests and the characteristics of each Eye Diagram that are required to meet compliance.

Prerequisite:

Compliance test setups (SATA, HDMI, and PCI-Express s etups are supplied with IConnect)

Eye Diagram Compliance Test Procedure

Prerequisites

Follow measurement best practices. (See page 12, Measurement Best Practices.)

Set the oscilloscope to display the correct waveforms. (See page 13, Displaying the Correct TDR Waveform.)

Set IConnect to acquire the necessary waveforms. (See page 18, Acquiring, Saving, and Loading Waveforms.)

1. Click the Eye Diagram Viewer button.

2. On the Compliance Test tab, click the Load Compliance Test button. Navigate

to and select the compliance test ﬁle (*.cts). IConnect lists the e ye setup tests in the Edit Compliance Test area and loads required masks in the Eye Diagram viewer.

24 IConnect® and MeasureXtractor™ Quick Start User Manual

3. Connect cables and ﬁxtures to the

oscilloscope. Do not connect the DUT.

4. Select the reference waveform from the

Waveform lis

Application Exa

mples

5. Click the Ac

button. IConnect acquires and plots the reference waveform on the TDR/T viewer tab.

6. Connect cables, ﬁxtures, and the DUT

to the oscilloscope.

7. Select the transmission waveform from

the Waveform list.

8. Click the Acquire Transmission Wfm

& Run Test button. IConnect acquires

the transmission waveform, runs all eye tests, and plots the results of the last test on the Eye Diagram viewer tab.

IConnect ﬁrst runs theTx tests, then runs the Rx tests.

quire Reference Wfm

9. The Test Status area lists the pass/fail

status of each test, and shows a color-coded Pass/Fail ﬁeld to show the overall test status. The last line of the test status is the name of the compliance test that was run.

IConnect® and MeasureXtractor™ Quick Start User Manual 25

Application Exa

10. Select the Eye Diagram viewer tab and

11. If one or more tests fail, IConnect

mples

clickanitemintheEye Setups list to show the Eye Di Measurements (if enabled) for that eye test.

displays an error message and shows which tests failed in the Test Status area list. You can then select the failed test item in the Eye Setups list to show the eye diagram for that test.

agram plot and the Eye

12. Click Run Test to run the test again. Note that the test may fail on occasion because IConnect applies random values to some parameters (such as jitter) to simulate real-signal conditions.

13. To s a

ve results, click the Save Results

button. Navigate to and select a directory in which to store results. IConnect

tes a folder in that directory and

crea names it with the compliance test name (as listed in the Name ﬁeld) appended

h a number (starting with 1).

wit

26 IConnect® and MeasureXtractor™ Quick Start User Manual

Application Exa

NOTE. In the Eye Diagram Options dialog box, the Save as Default button saves the eye setup parameters to the IConnect

registry on the

PC. These settings now become the new default settings when you select the New button in the Compliance Test tab (bottom of the tab, below the Eye Setups list), and is also used in the default New Compliance Eye Setup entry listed in the Eye Setups ﬁeld.

mples

The test resu

APNG-format

A copy of the

lt folder contains:

screen shot of the entire Eye Diagram viewer, for each eye setup test

source .cts ﬁle used by that test, but modiﬁed by IConnect during runtime for such things as the jitter

insertion parameters for the Rx eye test, which are generated as part of the test run

Atextﬁle with overall test results

Atextﬁle with the test results for each eye setup

IConnect® and MeasureXtractor™ Quick Start User Manual 27

Application Exa

Creating a Standard-Based Custom Eye Diagram Test

IConnect lets you create custom eye diagram tests based on the application-supplied standards (SATA, HDMI, or PCI-Express). Each standard deﬁnes the number and type of eye diagrams (eye setups) needed to pass the requirements of that standard.

NOTE. IConnect cannot automatically run all tests in a custom Eye Diagram test setup; you must select a test, c lick the Test

Eye tab, and click the Display Eye button.

Part of an eye diagram computation is setting up the eye diagram options, such as input sequence, data r ate and rise time. If you are computing an eye diagram without any crosstalk effects, you only need to set parameters for the DUT (victim) line. If you are including crosstalk effects in your eye diagram, you will need to set parameters for each aggressor line.

1. Click the Eye Diagram button to open a

2. On the Compliance Test tab, select the

mples

new Eye Diagram viewer.

standard against which to test from the

Procedure list.

3. Enter a name for your custom test in the Name ﬁeld.

4. Select the New Complete Eye Setup

item in the Eye Setups list. This is a default eye setup.

5. Click the Deﬁne Eye tab.

6. Click the DUT button and use the tabs and controls on the Eye Diagram Options dialog box to deﬁne the DUT

Eye Diagram parameters such as input sequence, data rate, jitter, mask test, and risetime. Click the Help button for information on the various parameters.

28 IConnect® and MeasureXtractor™ Quick Start User Manual

7. Enter the new name for the eye setup

test in the Eye Setup Name ﬁeld.

8. Use the Comment ﬁeld to add additional

information a Comments can contain up to 30,000 characters.

9. To save an eye setup to a ﬁle (*.mts),

click the Save or Save As button and navigate to of the setup ﬁle.

10. Click OK to apply the settings, close the

dialog box, and return to the Deﬁne Eye tab.

bout the eye setup.

a folder and enter the name

Application Exa

mples

11. To add aggressors to the eye setup

test, click the arrow buttons in the Aggressors ﬁeld to set the number of aggressors (up to eight). IConnect adds a button for each aggressor, which you click to set the parameters for each aggressor.

NOTE. If you cannot select the Use check

box next to the Aggressor buttons, then the aggressor does not have all its required waveforms loaded on the Legend page.

IConnect® and MeasureXtractor™ Quick Start User Manual 29

Application Exa

mples

12. To add more eye s compliance test, click the New button on the Compliance Test tab and enter the name of the

New Setup dialog box. Click the Deﬁne Eye tab and use the controls to deﬁne

the DUT and ag that eye setup.

13. To save the entire test (all eye setup ﬁles) to a single c ompliance test ﬁle (.cts), click the Save or Save As button on the C ompliance Test tab, navigate to a folder, and enter the name of the setup ﬁle. IConnect veriﬁes that the test contains all required eye setups and eye types, and will not save a ﬁle until the eye setup tests meet the requirements for the speciﬁed standard.

etups to the

eye setup in the Create

gressor parameters for

NOTE. You can load a saved eye setup ﬁle (*.mts) into your current Eye Diagram test. Click the Load button and navigate to

ect the eye setup ﬁle to load.

and sel

When Not to Run an Eye Diagram Compliance Test

When the reference or transmission waveform is missing (IConnect requires both)

When the number of eye setups in the test does not match what the selected standard requires

When eye setups do not have the correct eye type or position settings for the selected standard

When the Eye Compliance Test Procedure ﬁeld has Custom selected (you must select and run each test individually)

Creating Custom Eye Diagram Tests

The eye diagram is a method to visualize a digital data stream, in which each consecutive clock cycle is overlaid on top of the ﬁrst cycle in the data stream. The digital data pattern may be switching from 1 to 0, from 0 to 1, or stay at a 1 or 0 level. As a result, this continuously changing data stream, observed within a single cycle, produces a display resembling a human eye.

Eye diagram calculations require two measurements:

A reference TDR measurement of all connecting cables and/or probes without the DUT, on the positive switching channel.

A transmission TDT waveform on the positive-switching line at the far end of the DUT. Make sure to use exactly the same time base as for the reference waveform.

30 IConnect® and MeasureXtractor™ Quick Start User Manual

1. Acquire the reference and transmission

waveforms. (See page 18, Acquiring,

Saving, and Lo

ading Waveforms.)

Application Exa

mples

2. Click the Eye b

Diagram Viewer.

3. Click the Legend tab.

4. Click the DUT button and load the

reference a

5. To add aggressors, click the arrow

buttons in the Aggressors ﬁeldtoset the number of aggressors (up to eight). Click each Aggressor button to load the waveforms for that aggressor (reference, crosstalk, and optional ﬁxture).

6. Click the Deﬁne Eye tab.

utton to open the Eye

nd transmission waveforms.

7. Click the DUT button and use the ﬁelds,

tabs and controls on the DUT Eye Diagram Options dialog box to deﬁne the Eye Diagram parameters such as input sequence, data rate, jitter, mask test, and risetime.

If you have enabled aggressors, click each aggressor button and use the Aggressor Eye Diagram Options to set the aggressor parameters.

8. Enter the name of the eye diagram test

setupintheEye Setup Name ﬁeld.

9. Use the Comment ﬁeld to add additional

information about the eye setup. Comments can contain up to 30,000 characters.

IConnect® and MeasureXtractor™ Quick Start User Manual 31

Application Exa

10. Click the Save or Save As buttoninthe

11. Click the Test Eye tab. Set the

mples

Deﬁne Eye tab to save the eye diagram test.

parameters on this tab as required for your eye test

12. Click the Dis the eye diagram in the viewer. If you enabled mask, jitter, or noise testing, the Eye Diag pass/fail status of each test.

13. To evaluate different settings with the same signals, click the Deﬁne Eye tab, click t make changes to the test settings, and click the Apply button. IConnect redraws the eye settings.

play Eye button to display

ram Test area displays the

he DUT or Aggressor buttons,

diagram based on the new

EZ Z-Line DUT Testing

The IConnect EZ Z-Line viewer is speciﬁcally designed to do quick, single-button Z-Line computation for any number of

ce waveforms. The EZ Z-Line viewer lets you:

devi

sure and store waveforms and instrument settings from a known good device and test cable assembly to create a

Mea Golden Setup ﬁle

Use a single-button click to quickly acquire successive device waveforms, generate Z-Line impedance plots, and compare the device impedance plots against the Golden Setup

32 IConnect® and MeasureXtractor™ Quick Start User Manual

Prerequisites

Follow measurement best practices. (See page 12, Measurement Best Practices.)

Set the oscilloscope to display the correct waveforms. (See page 13, Displaying the Correct TDR Waveform .)

Set IConnect to acquire the necessary waveforms. (See page 18, Acquiring, Saving, and Loading Waveforms.)

Create a Golden Setup File

1. Use a golden DUT to display a correct

TDR waveform. The golden DUT is a DUT with known good impedance characteristics. (See page 13, Displaying the Correct TDR Waveform.)

2. Disconnect the golden DUT.

Application Exa

mples

3. Start IConnect. Establish communication

with the instrument. (See page 18,

Acquiring, Saving, and Loading Waveforms.)

4. Click the EZ button on the toolbar to

open the EZ Z-Line Viewer.

IConnect® and MeasureXtractor™ Quick Start User Manual 33

Application Exa

5. Select the waveform source from the

6. Click Golden Setup.

7. Click Reference to acquire and plot

8. Reconnect the Golden DUT to the test

mples

Waveform drop-down list.

the referenc

e waveform in the TDR/T

tab. This waveform is labeled Golden Reference.

cable assembly.

34 IConnect® and MeasureXtractor™ Quick Start User Manual

9. Click DUT to acquire and plot the Golden

DUT waveform in the TDR/T tab. This waveform is la

beled Golden DUT.

10. Set the measurement system impedance

) and threshold parameters if

required. The default values (50 Ω and 35%) are good for most measurements, but may need adjusting to accommodate your test setup.

11. (Optional) Click Comment and enter

comment text in the displayed dialog box. If the EZ Z-Line Viewer comment ﬁeld is empty, the Golden Setup comment will be copied into it. Otherwise the two comments are independent.

Application Exa

mples

12. Click Save Golden Setup to save the

Golden Setup ﬁletoaspeciﬁed location and name. Golden Setup ﬁles have the extension .gst.

Taking DUT Z-Line Measurements with a Golden Setup

Prerequisite. Connect the test cable assembly to the oscilloscope. Make sure to use the same type of test cable

bly (cable types, lengths, TDR probes, connectors, ﬁxtures, and so on) that was used to create the Golden Setup.

assem Do not connect the DUT at this time. Make sure that IConnect can communicate with the instrument. (See page 18, Acquiring, Saving, and Loading Waveforms.)

ktheEZ toolbar button to open the

1. Clic

EZ Z-Line Viewer.

2. Click Golden Setup.

IConnect® and MeasureXtractor™ Quick Start User Manual 35

Application Exa

3. Click Load Golden Setup. Navigate

4. Click OK to close the dialog box and set

5. Disconnect the DUT. Click in the

6. Click Reference in the DU T Setup

mples

to and select the Golden Setup ﬁle that you want to loa Golden Setup ﬁle that was created for the instrument to which you are connected, and that the s and instrument settings are being used to take the current set of measurements.

IConnect to this EZ Z-Line viewer.

Waveform list and s e lect the oscillosc channel to which the DUT will later be connected.

area. IConnect displays a message asking whether and how to align the new reference. Click OK to accept the recommended selection. IConnect adjusts the instrument settings to align the waveforms, acquires the new reference waveform, and plots the new reference waveform in silver on the TDR/T tab, with the label Reference.

d. Make sure to load a

ame test cable assembly

use this golden setup with

ope waveform source or

7. If you are not using a calibration waveform, select the Do not use 50 Ω

Cal check box.

8. If you are using a calibration waveform,

acquire a new calibration waveform by connecting a 50 Ω termination to the end of the test ﬁxture assembly and clicking 50 Ω Cal (opt). IConnect acquires and plots the new calibration waveform in silver. Remove the 50 Ω termination.

9. Connect the (nongolden) DUT to the test ﬁxture assembly.

36 IConnect® and MeasureXtractor™ Quick Start User Manual

10. Click Acquire DUT. IConnect acquires

the DUT waveform and plots it on the TDR/T and Z-Li labeled DUTn on the TDR/T tab, and Zn on the Z-Line tab, where n is an integer that increme acquired.

11. Click the Z-Line tab to compare the DUT

impedance impedance waveform. Determine if the DUT matches the Golden DUT waveform characte

ne tabs. The DUT plot is

nts for each DUT waveform

waveform with the GoldenZ

ristics.

Application Exa

mples

12. Disconne

13. Repeat steps 9 through 12 for each

DUT that you want to test and compare again shows that the plot from DUT acquisition ﬁve (labeled Z5 in the ﬁgure) does not match

Repeat steps 6 through 8 (with the DUT disconnected) at regular intervals during prol reference waveform. Acquiring a new reference waveform at regular intervals hel measurement drift.

ct the DUT.

st the Golden DUT. This example

the Golden Z-Line plot.

onged DUT testing to acquire a new

ps compensate for oscilloscope

IConnect® and MeasureXtractor™ Quick Start User Manual 37

Application Exa

mples

Automatically Creating S-Parameter Files (S-Parameter Wizard)

The IConnect S-parameter Wizard makes aquiring one-, two-, or four-port S-parameter waveform ﬁles fast, easy, and accurate when using a Tektronix sampling oscilloscope. The S-parameter wizard displays dialog boxes and messages to guide you through setting up and acquiring the necessary TDR and TDT measurements. The wizard uses the TDR/T waveforms and IConnect to generate S-parameter, Touchstone, Z-Line, and log ﬁles. You can load the ﬁles into IConnect or other tools for further analysis or modeling.

NOTE. The S-parameter Wizard runs on Tektronix 8000 Series sampling oscilloscopes on which IConnect is installed, or

on a pC with IConnect installed and a GPIB or LAN connection to a Tektronix 8000 Series sampling oscilloscope. If the oscilloscope or IConnect are not available, the S-parameter Wizard runs in demo mode. For other oscilloscopes, you will need to manually acquire and save the necessary TDR/T wav eforms and use the IConnect S-parameter computation function to create S-parameter ﬁles. (See page 39, Manually Creating S-Parameter Files.)

Prerequisites

Follow me

Differen Follow the deskew procedure in your oscilloscope manual, observe the difference in delays between the two channels in differential mode, and adjust for half of that difference by using the delta TDR function in the oscilloscope.

1. Click th

2. Select t

of ports and type of measurement).

3. Assign the ports to the oscilloscope channels. The S-parameter Wizard labels numbers.

4. Set the measurement parameters.The ﬁelds displayed depends on the selected measu

5. Click displays dialog boxes and messages to guide you through setting up and acqu Follow the displayed instructions.

See the Data Files Saved topic in the S-p of the output ﬁles generated for each measurement mode.

asurement best practices. (See page 12, Measurement Best Practices.)

tial measurements and long record acquisitions require that your signals arrive at the DUT at the same time.

e S-parameter Wizard button.

he measurement mode (number

the w aveforms with the port

rement mode.

Start. The S-parameter Wizard

iring S-parameter measurements.

arameter Wizard online help for a list

6. Click Help to get more information

etting parameters, using the

on s S-parameter Wizard, and the output ﬁles generated for each measurement mode.

38 IConnect® and MeasureXtractor™ Quick Start User Manual

Application Exa

NOTE. The S-parameter Wizard controls all oscilloscope settings during measurement sequences. Do not change any

oscilloscope s

ettings while the S-parameter Wizard is running.

mples

The S-paramet Z-Line waveform ﬁles.

NOTE. It is re

S-parameter Wizard automates acquiring S-parameter waveform data, which signiﬁcantly reduces the time it takes to acquire data. The S-parameter Wizard also reduces the chance of errors in setting up the instrument or in forgetting to take a set of

er Wizard invokes a copy of IConnect in the background to generate the S-parameter, Touchstone, and

commended that you use the S-parameter Wizard to acquire S-parameter waveforms for IConnect. The

port measurements.

Manually Creating S-Parameter Files

Frequency-domain scattering parameters (S-parameters) are a useful way to visualize the electrical properties of a system. They are a dual representation of TDR and TDT data in the frequency domain. Although S-parameters have historically been measured in the frequency domain using a network analyzer, you can use TDR and TDT measurements to obtain differential and mixed mode S-parameter data.

S-parameter calculations require a reference waveform and a DUT waveform. The DUT waveform can be either a reﬂection or transmission measurement.

Prerequisites

measurement best practices. (See page 12, Measurement Best Practices.)

oscilloscope to display the correct waveforms. (See page 13, Displaying the Correct TDR Waveform.)

Set the

nnect to acquire the necessary waveforms. (See page 18, Acquiring, Saving, and Loading Waveforms.)

Set ICo

rential measurements and long record acquisitions require that your signals arrive at the DUT at the same time.

Diffe Follow the deskew procedure in your oscilloscope manual, observe the difference in delays between the two channels in differential mode, and adjust for half of that difference by using the delta TDR function in the oscilloscope.

IConnect® and MeasureXtractor™ Quick Start User Manual 39

Application Exa

1. Acquire the necessary TDR and/or TDT

2. Load the S-parameter waveform ﬁles

mples

DUT and reference waveforms. The number of wave on the measurement mode (one-, two, or four-port) and type (single-ended or differential topic in the S-parameter Wizard online help for the number and type of DUT and referenc each mode.

into IConnect. (See page 18, Acquiring,

Saving, and

forms to acquire depends

). See the Data Files Saved

e measurements needed for

Loading Waveforms.)

3. Click the S S-parameter task tab.

4. Set the Source and Target waveform viewers.

5. Select the DUT and Ref (reference) wavefor

6. (Opti frequency content parameters. If not selected, IConnect c alculates the highest frequ

button to open the

ms in the Waveforms ﬁelds.

onal) Manually set the highest

ency content from the waveforms.

40 IConnect® and MeasureXtractor™ Quick Start User Manual

7. (Optional) Use a 50 Ω calibration

waveform created using a precision 50 Ω standard at th You also have a choice between open, short, and through reference calibration. (See page 41, S- Settings.)

8. Click the Compute button to open the

speciﬁed vi values using the default display format (dB (Mag)/Phase). Right-click in the viewer and s in a different format (Magnitude/P hase or Real/Imaginary).

e DUT reference plane.

Parameter Calibration

ewer and plot the S-parameter

elect Plot to view the data

Application Exa

mples

S-Parameter Calibration Settings

In the Calibration settings, when Ref type is set to Thru, and DUT Type is set to Insertion loss/xtalk, IConnect ignores the 50 Ω calibration waveform.

The Ref type ﬁeld speciﬁes what type of waveform to use in the waveform's Ref menu.

When Ref type is set to Open/Short, you must load a 50 Ω calibration waveform. To create a 50 Ω calibration waveform for a two-port transmission measurement, remove the DUT and connect a reference 50 Ω termination to the port to which the pulse will be applied from the TDR module, acquire and save the reﬂected waveform, and then enter that

ﬁle name in the Load 50 Ω Waveform ﬁeld.

Differential and Common Mode Measurements

erential (odd) and common (even) mode S-parameter measurements require different stimulus waveforms:

Diff

erential mode measurements: The oscilloscope must have the two stimuli switching in opposite directions (180° out

Diff of phase). For differential responses, subtract one response channel from the other.

Common mode measurements: The oscilloscope must have the stimuli switching in the same direction (in phase). For common mode responses, add the two response channels together.

IConnect® and MeasureXtractor™ Quick Start User Manual 41

Application Exa

mples

True Impedance P roﬁle (Z-Line) Measurement

The IConnect Z-Line impedance measurement analyzes the TDR waveforms to accurately determine the true impedance proﬁle of the device. An impedance proﬁle lets you observe the type and position of discontinuities alongaline. Youcanalso use the impedance proﬁle for signal integrity modeling.

The impedance proﬁle is the characteristic impedance of a PCB trace, package lead, or other transmission-line-type structure, measured as a function of distance. Transmission lines tend to have multiple discontinuities which cause reﬂections that superimpose on each other. TDR oscilloscope impedance measurements do not take these multiple reﬂections into account, resulting in possibly signiﬁcant impedance measurement errors for multiple-segment interconnects.

Z-Line impedance calculations require at least two TDR measurements:

A reference measurement of all connecting cables and/or probes without the DUT. If there are no interconnecting cables or probes to the DUT, the reference measurement is to the connector on the TDR measurement module.

A measurement with all interconnecting cables/probes and the DUT.

Prerequisites

Follow measurement best practices. (See page 12, Measurement Best Practices.)

Set the oscilloscope to display the correct waveforms. (See page 13, Displaying the Correct TDR Waveform.)

Set IConnect to acquire the necessary waveforms. (See page 18, Acquiring, Saving, and Loading Waveforms.)

1. Acquire the appropriate waveforms from the instrument or saved ﬁles. (See page 18, Acquiring, Saving, and Loading Waveforms.)

2. Click the Z button to open the Z-Line Computation task tab.

3. Verify that Z-Line is already selected in the Compute ﬁeld.

4. Select the TD Waveform Viewer window

in which you acquired the waveforms in step 1.

42 IConnect® and MeasureXtractor™ Quick Start User Manual

5. In the Waveforms group, select the

measured DUT TDR waveform in the

DUT ﬁeld, and t Step ﬁeld.

6. In the Parameters group, verify that the

ﬁeld (instrument impedance) is 50 Ω

(default).

7. Leave the Threshold ﬁeld at 35%

(default).

8. Click the Compute button. IConnect

calculates the true DUT impedance and adds the Z Viewer window.

he step waveform in the

-Line plot to the TD Waveform

Application Exa

mples

Standard Modeling

IConnect and MeasureXtractor TDR software helps you extract many different types of interconnect models from measurements. Model extraction in IConnect is a cooperative effort between IConnect’s underlying algorithms and the different model viewers available for creating, editing, and saving various types of models. Models are accessible both from the Model menu and from the Model toolbar buttons (toggled on or off from View > Toolbars > Model Toolbar).

Many of the model viewers have the ability to take measurements, extract a model, and validate it on your simulator, without having to open another window. For more complex modeling tasks, you can cascade individual models by using the editor in the Composite model viewer.

Model ﬁles are typically saved with .cir extensions, and may be loaded from the main menu using the File > Open command. More typically, they are loaded from the Composite model viewer.

IConnect® and MeasureXtractor™ Quick Start User Manual 43

Application Exa

Model Descriptions

Too lbar icon Model Description

mples

Source The Source model is an excitation model for launching an incident step into a DUT

model. The mod delay is the time elapsed from t=0 before the ramp begins, and the risetime is the 0%-100% rise time of the ramp. The amplitude is that of the incident voltage step injected int as the step launched into the DUT during measurement. For example, ~200 mV for HP TDRs, ~250 mV for Tektronix TDRs.

The Source m accuracy is reduced because the sharp corners at the transitions are likely to inject more high-frequency content into your DUT model than your real-world drivers will be injecting into your D

PiecewiseLinear (PW Source

Lumped

Single Line The Single Line m odel consists of nonuniform cascaded RLGC and/or transmission

Lossy Line As digital circuit speeds continue to rise, transmission line loss plays an increasingly

The PWL (pi step into a DUT model. The model consists of a set of time-voltage pairs, which describe a time-domain voltage waveform. The data points from which the waveform is built are deﬁne waveform to accurately represent the excitation conditions present during measurement.

The Lumped model is built up from RLGC, RLC, RC, or LC sections. The LC sections may be of pi, T, LC, or CL topology. The model may be used as a valid low-frequency

mation to an ideal single transmission line, or as a model for electrically small

approxi structures such as packages and connectors which are well represented by such a topology.

ential parameters to the model are the inductance L, the capacitance C,

The pot the resistance R, and the conductance G. A picture shows graphically the selected topology and how the R, L, G and C parameters are distributed in that topology. If a

stributed model is desired, you may increase the number of subsegments, in

more di which case each of the values shown in the picture is divided by that number and the subsegments are cascaded. Although this will not typically change the transmission

cteristics of your model, it will generally improve the reﬂection characteristics to

chara look more like those of a distributed transmission line.

line sections, and is useful for characterizing structures that are well represented as a

le conducting path. Examples would be microstrip traces and some package leads.

sing The graphical user interface of the s ingle line model editor determines the parameters and topology of each of the sections, although R and G values must be determined

ally if desired.

manu

ortant role in signal integrity analysis. Transmission line loss is caused in large part by

imp two factors: skin loss in the conductors, and dielectric loss. The primary results are rise time and amplitude degradation. Propagation delay becomes dependent on rise time,

amplitude degradation becomes dependent on clock frequency and bit sequences.

and The combination of these effects is eye closure at increased clock frequencies.

el parameters are step delay, step rise time, and step amplitude. The

o the DUT model, so in model veriﬁcation applications it should be the same

odel offers a quick, but less accurate, way to simulate a step input. The

UT. Simulation results should be interpreted accordingly.

ecewise-linear) source model is an excitation model for launching an incident

d through a graphical user interface, and are built from a measured voltage

44 IConnect® and MeasureXtractor™ Quick Start User Manual

Toolbar icon Model Description

Passive Equalizer

Two-port Subcircuit

Lumped Coupled

Symmetric

ed Lines

Coupl

Symmetric

led Lossy

Coup Lines

The Passive Eq equalizer used in a communication channel. The model opens the eye by applying a high pass ﬁlter characteristic (reducing signal loss at high frequencies) to the data stream of the transmiss capacitance C, and the resistance R. A picture shows graphically which topology has been chosen, and how the R, L, and C parameters are distributed in that topology.

The Two-port Subcircuit model lets IConnect incorporate SPICE-based modeling results into the ove included as part of a composite IConnect model.

All two-port subcircuit node deﬁnitions must be in the following order: input node, output node, and m

The Lumped signal propagating on the offender line transfers part of its energy onto the victim line.

The IConnect lumped coupled model is built up from RLCG, RLC, RC, or LC sections. The LC sec with inductive and capacitive coupling between them, it may be used as a valid low-frequency approximation to an ideal set of two coupled transmission lines, or as a model for represented by such a model.

The potential parameters to the model are the self and mutual inductance L1, L2, and L12, and conductance G. Although the picture in the modeling window shows the RLGC topology, the various LC topologies available are equivalent to the analogous topologies shown in the Lum the number of subsegments, in which case each of the values shown in the picture is divided by that number and the subsegments are cascaded.

The Symmetric Coupled Lines model consists of nonuniform cascaded coupled RLGC and/o represented as dual symmetric conducting paths. Examples are coupled microstrip traces and some coupled package leads or connector lines. The graphical user inter parameters and topology of each of the sections, although R and G values must be determined manually if desired.

The Symmetric Coupled Lossy Line model allows you to simulate skin effect and diel also allows you to predict the Eye Diagram degradation due to losses and ISI in the interconnects. You may also incorporate Eye Diagram closure effects due to crosstalk fro

electrically small coupled structures such as packages and which are well

the self and mutual capacitance C1, C2, and C12, the resistance R, and the

ped (uncoupled) model. If a more distributed model is desired, you may increase

r transmission line sections, and is useful for characterizing structures that are well

face of the symmetric coupled lines model editor assists the user in determining the

ectric loss, together with intersymbol interference (ISI) and crosstalk effects. It

m neighboring line pairs.

Application Exa

ualizer model is built up from RLC or RC sections to model a passive

ion line. The potential parameters to the model are the inductance L, the

rall model. Any SPICE model with input, output, and ground nodes may be

odel ground node.

Coupled models the crosstalk energy coupling between adjacent lines. The

tions may be of pi, T, LC, or CL topology. Because it models two structures

mples

IConnect® and MeasureXtractor™ Quick Start User Manual 45

Application Exa

Too lbar icon Model Description

mples

Termination

Data Driven Models (Sin and Coupled)

The terminati only model parameter is resistance, since the model consists of a resistor to ground. To emulate an open circuit, use a resistance value that is large compared to the characterist compared to the characteristic impedance of the measurement system. For a 50 Ω system, for example, a typical open circuit termination r esistance value would be 5k Ω and a short ci

The data-driven models allow you to bypass any manual intervention in the modeling

gle

process usi automatic model extraction for two-port and four-port models, which correspond to single-line and coupled-line circuits. (See page 49, Advanced Modeling

(MeasureXt

Data driven model extraction results in a SPICE netlist which very accurately r eplicates the behavior of the measured device. The passivity of the model is guaranteed by the extractio recognizable. As a result, you should not use data-driven models if you intend to adjust parameters in the resulting model.

on model replicates the passive termination conditions of the DUT. The

ic impedance, while for a short circuit, use a resistance value that is small

rcuit termination resistance value would be 1Ω.

ng IConnect’s MeasureXtractor modeling technology. IConnect supports

ractor™).)

n process. The resulting netlist cannot be adjusted, and will not be structurally

Example Standard Model Process

Prerequisites

Follow measurement best practices. (See page 12, Measurement Best Practices.)

Set the oscilloscope to display the correct waveforms. (See page 13, Displaying the Correct TDR Waveform.)

Set IConnect to acquire the necessary waveforms. (See page 18, Acquiring, Saving, and Loading Waveforms.)

1. Click the Lossy Line button.

2. Selec

3. Click the buttons in the Select

t the termination Type (Open or

Matched) on the Measure tab.

Waveforms area to select and load the

ired waveforms.

requ

46 IConnect® and MeasureXtractor™ Quick Start User Manual

4. Select the Model tab.

5. (Optional) Click the Options button and

set the Max. Iterations that IConnect performs befo the measurement Precision setting at which to stop calculations (calculations stop when ICo precision value setting).

6. Set the Lumped Model parameters.

Lumped Model settings affect how the Lossy Line model is written to a ﬁle.

Enter a realistic rise time number to decrease the required number of subsegments for the model to be accurate to that rise time. Alternatively, you can manually decrease the number of subsegments. You need to have at least three segments per length of TDR rise time.

re calculations stop, and

nnect reaches the

Application Exa

mples

7. Set the Netlist parameters. Netlist

settings affect how the Lossy Line modeliswrittentoaﬁle. Use the Scale parameters by ﬁeld to generate a per-unit length model, or to easily scale the length of the model.

IConnect® and MeasureXtractor™ Quick Start User Manual 47

Application Exa

8. Click the Compute button. IConnect

9. (optional) Change one or more Loss

10. To save the model, right-click in the

11. To view the model netlist, right-click in the

mples

calculates the DUT Loss Parameter characterist waveforms.

Parameter ﬁelds and click the Evaluate button to tes change the simulated waveforms. Use the Fix check boxes to prevent the current val

waveform plot and select Save Model.

waveform

ics and plots the simulated

t how different values

ue from changing.

plot and select View Netlist.

12. To simulate the m odel, select the Simulate tab and click the Simulate

button. IConnect generates new viewer windows as needed and prompts you to enter the location at which to save the simulation ﬁles.

48 IConnect® and MeasureXtractor™ Quick Start User Manual

Model Extraction Tips

Keep models as simple as possible. Simple models are faster to simulate, easier to troubleshoot, and easier to

explain to a colleague or customer. One effective way to create a simple model is to ﬁlter your measured data prior to model extraction to be sure that you are modeling for the rise time at which your circuit is intended to operate, and not modeling an order of magnitude higher than necessary. Also, be certain that you are modeling your DUT, and not the parasitics associated with your measurement system.

Work with models directly in the composite model viewer. Working directly in the composite model viewer will

save you the intermediate step of writing a model to disk and later having to reload it into the composite viewer for veriﬁcation.

Know which models are most effective for which modeling tasks. Some assistance is available in the reference

material, but a certain amount of expertise must be gained through experience and through physical understanding of the problem at hand. Tektronix is also available to give advice on modeling issues.

Make sure that your measured data is accurate. Your models can only be as accurate as your measurements, so

taking the time to do it right will pay off later. Ensuring that shorts are shorts, that opens are opens, and performing other checks on measured data will save time and headache in troubleshooting later.

Advanced Modeling (MeasureXtractor™)

Whereas standard modeling provides an engineer with the tools to create a detailed topological model of an interconnect, MeasureXtractor provides a fast way to create a data-driven model based on the measurements through a known good interconnect. You can use this “black box” functionality. MeasureXtractor data-driven models let you simulate any interconnect structure, and include both time dependent (reﬂection, ringing, crosstalk) and frequency dependent (frequency loss) interconnect behavior.

model in the IConnect Link Simulator to test and verify the interconnect

Application Exa

mples

MeasureXtractor modeling can use time domain reﬂectometry and transmission (TDR/T) measurements or frequency dependent S-parameter data. The size of the model is proportional to the interconnect size and complexity. The passivity, stability and causality of the models are guaranteed.

Waveform Acquis itio n and Setup

Review measurement techniques if necessary. (See page 12, Measurement Best Practices.) In addition to the best practices given in that section, it is particularly important when taking MeasureXtractor measurements to select a window that is long enough to allow the DUT waveforms to completely settle to their steady state DC levels. High-frequency DUT analysis requires the signal to settle to make an accurate analysis.

When to Use Data-Driven Models

Data Driven models are best used for devices which are electrically short or medium-sized. A rough rule of thumb is that the device should be fewer than 20 wavelengths in length. Longer devices may take too long to extract. Another equivalent rule of thumb is that the electrical length of the device shouldn’t be more than 100 times the rise time of the signal you will use to excite the model. This is because the extraction time increases for waveforms with a large number of data points. Furthermore, simulation time of the resultant model will also increase.

Prerequisites

Follow measurement best practices. (See page 12, Measurement Best Practices.)

Set the oscilloscope to display the correct waveforms. (See page 13, Displaying the Correct TDR Waveform .)

IConnect® and MeasureXtractor™ Quick Start User Manual 49

Application Exa

mples

Set IConnect to acquire the necessary waveforms. (See page 18, Acquiring, Saving, and Loading Waveforms.)

All the waveforms must be acquired with 50 Ω probes, ﬁxtures, or cables connected to all the DUT ports.

The cables, probes, and ﬁxtures used to connect the DUT to both channels of the TDR oscilloscope must be of the same length.

Reference wav DUT and left open-ended.

1. Determine the type of model that you want to extract (single or coupled line).

2. Select the appropriate type model to open the Data Driven viewers and task tabs (the example shows the data-driven Single Line Viewer and Task tabs).

You can also select the MeasureXtractor model from the Model toolbar.

3. Select Time or Frequency domain data for MeasureXtractor data driven modeling. The parameters displayed depend on the selected domain type.

If you select Time domain, you can acquire the data directly from a TDR oscilloscope, load saved waveform ﬁles, or select waveforms from an open Viewer window. If you select Frequency domain, you will need to acquire and save the waveform data as frequency-dependent Touchstone ﬁles beforehand, with port 1 (and 3 for coupled line) as inputs, and 2 (and 4 for coupled line) as outputs.

eforms must be acquired at each port, with the cables, probes, and ﬁxtures disconnected from the

4. Load or acquire the necessary waveforms for each port.

50 IConnect® and MeasureXtractor™ Quick Start User Manual

5. Select the Model tab and click the

Extract button. The R esults area lists

the number of p encountered during the extraction.

oles and any errors

Application Exa

mples

6. To save t he mo

TDR/T viewer and select Save Model.

Use the Syntax ﬁeld i n the Save dialog box t (variations on SPICE, or the IConnect Linear Simulator).

7. To view the model netlist, right-click in the

TDR/T view

8. To simulate the model, select the

Simulate tab and click the Simulate

button. IConnect generates and displays associated viewers during the simulation, and also prompts you for the location to store the simulation results.

The simulator speciﬁed in the Tools/Options menu on the Simulate tab must match the Syntax ﬁeld entry in step 6.

del, right-click in the

o set the model ﬁle syntax

er and select View Netlist.

IConnect® and MeasureXtractor™ Quick Start User Manual 51

Application Exa

9. If you need to increase the precision

mples

with which IConnect models the TDR reference por PWL Source window, decrease the Max Error value and click Partition to repartition sure to save it before continuing.

t data, open the appropriate

the PWL Source model. Make

10. After the s simulated waveforms are placed in the Composite model waveform viewers. Click the T correlation. The correlation is exact in both time and frequency domains.

When usin IConnect uses ports 1 and 3 as the input ports, and ports 2 and 4 as the output ports. U reading the Touchstone ﬁle if the ﬁle uses a different port numbering scheme.

See the Online help for more information on MeasureXtractor functions and the Model Composite Editor.

imulation is complete, the

DR/T or S(f) tabs to view the

g Touchstone ﬁles, note that

se the Port Mapping option when

52 IConnect® and MeasureXtractor™ Quick Start User Manual

Index

Symbols and Numbers

1-port differential setup, 11 1-port single-ended setup, 10 2-port diffe 2-port single-ended setup, 10 4-port single-ended setup, 11

rential setup, 11

Acquire wa

Acquiring, Saving, and Loading

Advanced Modeling

Algorith Align DUT waveforms (EZ Z-line), 7 Application examples

Application Examples

Apply a Autoscale waveform plot, 8 Auxiliary toolbar, 5

veforms from

oscilloscope, 18

Waveforms

(MeasureXtractor), 49

m toolbar, 5, 6

creatin

Eye Diagram compliance

S-parameter Wizard, 38

,18

g custom standard-based

Eye Diagram test, 28

test, 24

low pass ﬁlter, 7

ration toolbar, 6

Calib Change viewer waveform properties

(color, label, cursor readouts,

rameter), 7

S-pa change waveform plot units, 8 Comparing DUT Z-Lines to a

rence DUT, 32

refe Compliance information, ii Compliance testing, Eye

gram, 24

Dia Connecting the DUT, 10 Convert S-parameter waveform, 7

ate a golden setup ﬁle (EZ

Cre

Z-Line), 33 Create a waveform label, 7

eate a waveform view label, 8

Cr Creating a custom Eye Diagram

test, 28, 30

Cursor view, 5 Cursors and cursor readouts, 9

Data-drive

Delete a waveform, 7 Device unde

Differential and common

Display correct TDR waveform, 13 Display waveform in Spectrum

Drag-and-Drop waveforms or

DUT setup

n models model

description, 46

r test (DUT)

connections, 10

measureme

view, 7

ﬁles, 21

nts, 41

s, 10

Enhanced Accuracy mode (long

records), 12

mental considerations, ii

Environ Equipment recycling, ii Evaluation version, 1

e standard model

Exampl

process, 46

Execute oscilloscope commands

ﬁle, 22

from a Export to Touchstone format ﬁle, 8 Export waveform data, 7

t waveform to a csv ﬁle, 22

expor Export waveform to a Touchstone

ﬁle, 22

rnal monitor (optional), 1

Exte Eye Diagram compliance test

caveats, 30

iagram tests

Eye D

compliance testing, 24

creating custom nonstandard

ed, 30

bas

creating custom standard-based

tests, 28

standard based, 30

non EZ Z-Line DUT testing, 32

File Operatio

execute oscilloscope

commands from a ﬁle, 22

export wavef

export waveform to a

load oscilloscope settings from

restore os

run oscilloscope commands

Save a single waveform, 22 save oscilloscope settings to a

Save waveforms to a new

orm to a csv

ﬁle, 22

Touchstone

a ﬁle, 22

from a ﬁle, 22

from a ﬁle,

ﬁle, 22

location, 22

ﬁle, 22

cilloscope settings

ing S-parameter ﬁles, 39

Generat GPIB board, 1 GPIB settings, 3

SB interfaces, 4

GPIB/U

Hardware key (dongle), ii, 2 Hide a waveform, 7

dance versus frequency

Impe

waveform, 7

Import w aveform or data into a

view

Import waveform or other data into

the view, 8

tallation (requirements and

Ins

procedure), 1

Installing IConnect software, 1

egration and differentiation

Int

(waveform math), 23

Interface, 3

IConnect® and MeasureXtractor™ Quick Start User Manual 53

Index

Key features, iii

Label a waveform, 7 Label a wavef LAN interface, 3 Load oscilloscope settings from a

ﬁle, 22

Load saved waveforms into

IConnect, 21 Lossy Line m Lumped Coupled model

description, 45 Lumped mod

orm view plot, 8

odel description, 44

el description, 44

Maximum version, 1 Measurement best practices

adequate

deskew channels, 13

Display

Make good connections to

observe electrostatic prevention

use sig

Warm up the oscilloscope, 12 MeasureXtractor, 49 Memory Menu Bar, 5 Minimum system requirements, 1

um version, 1

Minim Model descriptions

data-driven models, 46

Lossy

Lumped, 44

Lumped Coupled, 45

Piec

Single Line, 44

Sou

Symmetric Coupled Lossy

Ter

Two-port Subcircuit, 45

XXX, 45

del extraction tips, 49

waveform record

length, 13

correct TDR

waveform, 13

DUT, 11

guidelines, 13

nal averaging, 13

requirements, minimum, 1

Line, 44

ewise-Linear (PWL)

Source, 44

rce, 44

Lines, 45

mination, 46

Model toolbar, 6 Move a waveform

Operating basics, 5 Optional external monitor, 1

Passive Equ

Piecewise-Linear (PWL) Source

Pop-up function descriptions, 10 Product end-of-life handling, ii

alizer model

description, 45

model descr

iption, 44

Reset wav Restore oscilloscope settings from a

Run IConn

Run oscilloscope commands from a

eform position, 7

ﬁle, 22

ect on a Tektronix

oscilloscope, 2

ﬁle, 22

S-parameter computation, 38 S-parameter ﬁles, generating, 39

meter toolbar, 6

S-para Save a single waveform, 22 Save a waveform, 7

scilloscope settings to a

Save o

ﬁle, 22

Save waveforms from

loscope, 20

oscil

Save waveforms to a new

location, 22

ct a waveform, 7

Sele Set waveform view horizontal and

vertical scales, 8

all waveform traces in plot, 8

show Show or remove a cursor readout, 7 Single Line model description, 44

tware versions

Sof

Evaluation, 1 Maximum, 1

nimum, 1

Mi Standard, 1

Source model description, 44

Standard Modeling, 43 Standard toolb Standard version, 1 Starting and stopping the

application, Status Bar, 5 Supported instruments, iii Supported op Symmetric Coupled Lossy Lines

model description, 45 System requi

ar, 5

erating systems, 1

rements, minimum, 1

Task tabs, 5, 9 TekVISA, 1, 2, 3 Terminati The Status Bar, 10 The user interface, 5 The Wavefo Tool Bar, 5 Toolbar, 5 Touchsto True impedance proﬁle (Z-Line)

Two-por

on model description, 46

rm/Data views, 6

ne, 8

measurement, 42

t Subcircuit model

description, 45

Undo zoom or Autoscale

ion, 8

operat Using EZ Z-Line, 35

Waveform Math, 23

54 IConnect® and MeasureXtractor™ Quick Start User Manual

Index

Waveform trace operations

align DUT wavef

Z-line), 7 apply a low pass ﬁlter, 7 change wavefo

(color, etc.), 7 convert s-parameter

to impedance

frequency, 7 create a waveform label, 7 delete a wave display a cursor readout, 7 display waveform in Spectrum

view, 7 export waveform data, 7 hide a waveform, 7 label a wav move a waveform, 7 remove a cursor readout, 7 reset wave save a waveform, 7 select a waveform, 7 show a cur

orms (EZ

rm properties

form, 7

eform, 7

form position, 7

sor readout, 7

vs.

Waveform view operations

Autoscale, 8 change waveform plot units, 8 create a waveform view label, 8 export to Touc

ﬁle, 8

import waveform or data into a

view, 8 label a waveform view, 8 set waveform view horizontal

and vertical show all waveform traces in

plot, 8 undo zoom or

operation, 8 zoom on region, 8

Waveform/

data views, 5

hstone format

scales, 8

Autoscale

Z-Line DUT testing, 32 Zoom on waveform region, 8

IConnect® and MeasureXtractor™ Quick Start User Manual 55

Tektronix IConnect,MeasureXtractor Primary User

Specifications and Main Features

Frequently Asked Questions

User Manual

Table of Contents

Environmental Considerations

Preface

Key F eatures

Documentation

Conventions Used in This Manual

Installation

IConnect Software Versions

MinimumSystemRequirements

Installing Software

Starting and Stopping the Application

RunningIConnectonaPC

The User Interface

Connecting the DUT

Measurement Best Practices

Displaying the Correct TDR Waveform

Acquiring, Saving, and Loading Waveforms

File Operations

Waveform Math

Application Examples

Eye Diagram Compliance Testing

EZ Z-Line DUT Testing

Automatically Creating S-Parameter Files (S-Parameter Wizard)

Manually Creating S-Parameter Files

Standard Modeling

Advanced Modeling (MeasureXtractor™)