x
DPOACQSYNC
Dual Oscilloscope Synchronization Kit
ZZZ
Instructions
*P071310200*
071-3102-00
xx
DPOACQSYNC
Dual Oscilloscope Synchronization Kit
ZZZ
Instructions
www.tektronix.com
071-3102-00
Copyright © Tektronix. All rights reserved. Licensed software products are owned by Tektronix or its subsidiaries or suppliers, and are
protected by na
tional copyright laws and international treaty provisions.
Tektronix pro
previously published material. Specifications and price change privileges reserved.
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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 this product will be free from defects in materials and workmanship for a period of three (3) months from the
date of shipment. If any such product proves defective during the warranty period, Tektronix, at its option, either will repair the defective
product without charge for parts and labor, or will provide a replacement in exchange for the defective product. Parts, modules and
replacement products used by Tektronix for warranty work may be new or reconditioned to like new performance. All replaced
parts, modules and products become the property of Tektronix.
In order to obtain service under this warranty, Customer must notify Tektronix of the defect before the expiration of the respective
warranty period and make suitable arrangements for the performance of service. Customer shall be responsible for packaging and
shipping the defective product to the service center designated by Tektronix, with shipping charges prepaid. Tektronix shall pay for
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located. Customer shall be responsible for paying all shipping charges, duties, taxes, and any other charges for products returned to
any other locations.
This warranty shall not apply to any defect, failure or damage caused by improper use or improper or inadequate maintenance and
care. Tektronix shall not be obligated to furnish service under this warranty a) to repair damage resulting from a ttempts by personnel
other than Tektronix representatives to install, repair or service the product; b) to repair damage resulting from improper use or
connection to incompatible equipment; c) to repair any damage or malfunction caused by the use of non-Tektronix supplies; or
d) to service a product that has been modified or integrated with other products when the effect of such modification or integration
increases the time or difficulty of servicing the product.
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 REPAIR OR REPLACE DEFECTIVE PRODUCTS
IS THE SOLE AND E XCLU S IVE REMEDY PROVIDED TO THE CUSTOMER FOR BREACH OF THIS WARRANTY. TEKTRONIX
AND ITS VENDORS WILL NOT BE LIABLE OR ANY INDIRECT, SPECIAL, INCIDENTAL, O R CONSEQUENTIAL DAMAGES
IRRESPECTIVE OF WHETHER TEKTRONIX OR THE VENDOR HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH
DAMAGES.
[W5 – 15AUG04]
Table of Contents
General safety summary ... .... . ... . . ... . ... . . ... . ... . . ... . ... . . ... . ... . . ... . . .. . . ... . . .. . . ... . . ... . ... . . ... . ... . . ... . . .. . . ... . . .. . . .. iii
Preface ................................................................................................................................. v
Documentation ...................................................................................................................v
Introduction ... . . .. . . ... . . ... . ... . . ... . ... . . ... . ... . . ... . ... . . ... . ... . . ... . . .. . . ... . . .. . . ... . . .. . . ... . . .. . . ... . . .. . . ... . . .. . . ........... 1
Synchroniz
Preliminary setup considerations ..................................................................................................... 2
Equipment setup....................................................................................................................... 5
Deskew pro
Deskew procedure (automated) . ... . . ... . ... . . ... . ... . . ... . . .. . . ... . . ... . ... . . ... . . .. . . ... . . .. . . ... . . ... . ... . . ... . . .. . . ... . . ... . 7
Deskew procedure (manual).. . . ... . . ... . ... . . ... . . .. . . ... . . ... . . .. . . ... . . ... . ... . . ... . ... . . ... . . ... . ... . . ... . . ... . ... . . ... . . ... 10
Acquisiti
Conclusion ............................................................................................................................ 14
Appendix A . .. . . .. . . ... . ... . . .. . . ... . ... . . ... . ... . . .. . . .. . . ... . ... . . .. . . ... . ... . . .. . . ... . ... . . .. . . ... . ... . . .. . . ... . ... . . .. . . ... . ....... 15
067-2431
Product description.. . ... . . ... . ... . . .. . . ... . . .. . . ... . ... . . .. . . ... . . .. . . ... . ... . . .. . . ... . . .. . . ... . ... . . ... . ... . . ... . ... . . .. . . ... . .15
Index
ation Methods . ... . . .. . . ... . . .. . . ... . ... . . ... . ... . . ... . ... . . ... . ... . . .. . . ... . . .. . . ... . ... . . ... . ... . . .. . . ... . . .. . . ... . . 1
cedure. . ... . ... . . ... . ... . . ... . . .. . . ... . . ... . ... . . ... . . .. . . ... . . ... . ... . . ... . . ... . ... . . ... . ... . . ... . ... . . ... . . .. . . ... . . ... . . 6
on procedure ... . . ... . . .. . . ... . . ... . ... . . ... . . ... . ... . . ... . . ... . . .. . . ... . . ... . ... . . ... . . ... . . .. . . ... . . ... . . ... . ... . . ... . ... . . 13
-xx Deskew Fixture ................................................................................................... 15
Table of Content
s
Dual O scilloscope Synchronization Kit Instructions i
Table of Content
s
ii Dual Oscilloscope Synchronization Kit Instructions
General safety s
ummary
General safet
Review the following safety precautions to avoid injury and prevent damage to this product or any products connected to it.
To avoid potential hazards, use this product only as specified.
Only qualified personnel should perform service procedures.
While using this product, you may need to access other parts of a larger system. Read the safety sections of the other
component manuals for warnings and cautions related to operating the system.
To avoid fire or personal injury
Connect and disconnect properly. Do not connect or disconnect probes or test leads while they are connected
to a voltag
Connect an
probe to the circuit under test. Connect the probe reference lead to the c ircuit under test before c onnecting the probe
input. Disconnect the probe input and the probe reference lead from the circuit under test before disconnecting the probe
from the m
Observe a
product manual for further ratings information before making connections to the product.
The inputs are not rated for connection to mains or Category II, III, or IV circuits.
Connect the probe reference lead to earth ground only.
e source.
d disconnect properly.
easurement instrument.
ll terminal ratings.
y summary
Connect the probe output to the measurement instrument before connecting the
To avoid fire or shock hazard, observe all ratings and markings on the product. Consult the
Do not apply a potential to any terminal, including the common terminal, that exceeds the maximum rating of that terminal.
Do not operate without covers. Do not operate this product with covers or panels removed.
Do not operate with suspected failures. If you suspect that there is damage to this product, have it inspected by
qualified service personnel.
Avoid exposed circuitry. Do not touch exposed connections and components when power is present.
Do not operate in wet/damp conditions.
Do not operate in an explosive a tmosphere.
Keep product surfaces clean and dry.
Dual O scilloscope Synchronization Kit Instructions iii
General safety s
Termsinthismanual
These terms may appear in this manual:
WARNING. Warning statements identify conditions or practices that could result in injury or loss of life.
CAUTION. Caution statements identify conditions or practices that could result in damage to this product or other property.
Symbols and terms on the product
These terms may appear on the product:
DANGER indicates an injury hazard immediately accessible as you read the marking.
WARNING indicates an injury hazard not immediately accessible as you read the m arking.
CAUTION indicates a hazard to property including the product.
The following symbol(s) may appear on the product:
ummary
iv Dual Oscilloscope Synchronization Kit Instructions
Preface
This manual describes connecting, deskewing, and synchronizing 2 instruments to get 4 channels sampling at 100 GS/s.
Documentation
Preface
To read about Use these documents
Connecting, deskewing, and synchronizing 2 instruments to get 4 channels
sampling at 100 GS/s
In-depth instrument operation, user in terface help, G PIB commands Access the online help from the Help menu
*
To access the documentation that is installed on your instrument, click Start in the taskbar and select All P rograms > TekApplications.
Read this Instruction Manual.
on the host instrument.
*
Dual O scilloscope Synchronization Kit Instructions v
Preface
vi Dual Oscilloscope Synchronization Kit Instructions
Introduction
Tektronix DPO/DSA/MSO70000C/D instruments above 12 GHz in bandwidth provide 50 GS/s sampling rate on each of 4
channels simultaneously, or 100 GS/s sampling rate on 2 channels in interleaved mode. With interleaved operation you can
use two instruments, synchronized together, to get 4 channels sampling at 100 GS/s. The DPOACQSYNC kit provides the
hardware needed to connect two DPO70000C/D Series Oscilloscopes for synchronous acquisition. In addition, using the
Dual Oscilloscope Synchronization software provides automatic setup and removal of channel to channel skew on all 4
channels with one push of a button.
There are several ways to configure a two-instrument system for synchronized acquisition, with varying levels of alignment
accuracy. This manual describes the most precise method to align acquisitions between two instruments.
Synchronization Methods
Channel sample synchronization (alignment of time related events across two instruments) consists of three elements:
channel sk
channel skew. Sample alignment is attained using a common reference clock for both oscilloscopes. Trigger alignment is
achieved by carefully applying the same trigger signal to each oscilloscope by a matched-length path. Sample and Trigger
alignmen
this manual, you can keep the effects of random jitter to a minimum.
ew, acquisition sample alignment, and trigger alignm ent. Deskew adjustment of individual channels addresses the
t are both subject to random jitter that is difficult to remove from the acquisition. Using the techniques described in
Introduction
Synchronization
To facilitate using 2 instruments to achieve 4 channels at 100 GS/s, Tektronix DPO/DSA70000D and DPO/DSA/MSO70000C
models include enhancements to the system clock to provide tight timing synchronization between the two instruments. In
interleave mode, using a 10 MHz external reference clock, the enhanced system clock provides acquisition sampling that is
synchronized to ±500 fs RMS for single acquisitions from minimum acquisition time to 10 us, across two instruments. The
synchronization is maintained to ≤ 2 ps RMS from 100 us up to the maximum acquisition time of the instruments (increases
somewhat linearly between 10 us and 10 ms, and then levels off at approximately 2 ps).
Deskew
The synchronized start of acquisition (triggering) of two instruments is affected by two aspects of operation.
First, it is necessary to deskew the channels. Coarse synchr onization of the triggering events is attained by physically
matching path lengths from the trigger source (the external trigger signal) using matched cable lengths and a power
der. Fine control of synchronization is achieved using the automated deskew function in the Tektronix Dual Scope
divi
Synchronization application or the deskew feature for each of the instrument channels. The channels on a single instrument
are deskewed to each other. In addition, the two instruments are deskewed to remove minor differences in propagation
ugh their trigger path and input channels. Deskew can be adjusted in 1 ps increments, with the ability to apply a
thro
maximum deskew of ±75 ns to each channel
Trigger synchronization is also affected by trigger jitter in each system. The trigger jitter is dependent on the minor differences
in the trigger path between the two oscilloscopes. In addition, the slew rate of the trigger signal will affect the trigger jitter.
recommended trigger signal for both oscilloscopes in this manual is an output of the fast edge source board.
The
Dual O scilloscope Synchronization Kit Instructions 1
Preliminary set
up considerations
Preliminary setup considerations
Recommended equipment
The DPOACQSYNC kit provides all the hardware needed to support using two DPO 70000 series oscilloscopes with
synchronized acquisitions. With this kit, you can acquire 4 channels at up to 33 GHz bandwidth and 100 GS/s to capture
extremely fast signals. The kit accessories provide precise alignment between acquisitions on two DPO/DSA/MSO70000
oscilloscopes. Using the kit hardware and the kit procedure, you can achieve oscilloscope to oscilloscope skew of 2 ps
RMS. As part of this kit multiple matched length cables ar e provided. In addition, a fast edge source for aligning the
acquisitions is included.
The DPOACQSYNC board receives power from a USB slot and has 1 coax input and 4 coax outputs. The coax input
requires a square wave between -2.0 V to +5.0 V. The board produces 2 differential outputs that are 1 V peak to peak. The
input frequency can be up to 1 MHz. The output signals are used to synchronize two oscilloscopes.
The following list shows the equipment included in the DPOACQSYNC kit.
Table 1: DPOACQSYNC Kit contents
Accessory Quantity Part number Description
1 1 174-6213-00
2 2 174-6211-00
3 1 174-6212-00
4 3 012-0076-00
5
6 1 174-6025-00
7
8 1 103-0469-00
9 1 650-5659-00 Fast edge source
10 1 174-6215-00
11 1 015-0572-00
12 1 174-6214-00
13 1 003-1929-00
1 174-4401-00
1 003-1890-00 Adjustment tool
5
1 016-2060-00
321-8010-00
Pair of unmatched 2.92 mm coaxial cables (12 inch, 30 cm)
Pair of delay matched (1 ps) 2.92 mm coaxial cables (12 inch, 30 cm)
Delay matched (1 ps) 2.92 mm coaxial cables (12 inch, 30 cm)
BNC cable (20 inch, 51 cm)
USBAtoBcable
SMA cable (72 inch, 183 cm)
BNC T adapter
2.92 mm terminators, 50 Ohm (shown with fast edge source)
2:1 SMA power divider
SMA female to BNC male adapter
4:1 SMA power divider
SMA torque wrench, 8 inch pound
Case, hard, DP OACQSYNC
2 Dual Oscilloscope Synchronization Kit Instructions
Preliminary set
up considerations
Figure 1: Kit accessories
Calibrate the signal path (SPC)
Use the following procedure to compensate the internal signal acquisition path. Perform this procedure if the ambient
temperature has changed more than 5 °C (9 °F) since you performed the last signal path compensation. Perform the signal
path compensation once a week. Failure to do so may result in the instrument not meeting warranted performance levels.
1. Power on and wait for the instrument to complete its warm up period before continuing with this procedure.
2. Disconnect any signals (cables) you have attached to the input channels.
3. If the Tekscope user interface (UI) is in Buttons mode, set the instrument UI to Menu mode.
4. Select Instrumen t Calibration from the Utilities menu.
Dual O scilloscope Synchronization Kit Instructions 3
Preliminary set
5. Note any instructions that appear under Calibration Instructions in the control window.
6. Click Calibrate to begin the procedure. The procedure will take several minutes to complete.
up considerations
External trig
Optimal trigger jitter performance is attained by using one of the analog channels as a trigger source. When using 100 GS/s
sampling, you can use one of the disabled channels (for example CH2 and CH4 when using CH1 and CH3 as the data
inputs) as a trigger source without disturbing the 100 GS/s operation. You can use any of the PinPoint trigger features
in this configuration.
ger
Connector torque
To ensure t
he best signal fidelity, all connectors should be tightened to 8 inch lbs using the DPOACQSYNC torque wrench.
Fast edge source (deskew fixture)
This illustration identifies the controls, connectors, and indicators on the fast edge source included in the DPOACQSYNC kit.
Thefastedgesourcecanalsobeusedasaprobedeskewfixture. See Appendix A for more details on the use of this fixture.
Figure 2: Deskew fixture controls, connectors, and indicators
4 Dual Oscilloscope Synchronization Kit Instructions
Equipment setup
Parent and child instrument connections
In the setup and subsequent procedure that follows, the terms parent and child are used to differentiate between the
instrument that is the reference for acquisition alignment (the parent), and the instrument that receives the alignment
reference (the child). The instruments used in synchronization are linked through the use of an external trigger source,
and a commmon reference source.
External trigger source
The analog c hannels are used as the source for the oscilloscope trigger; using the analog channels provides the least trigger
suring that the signals are tightly aligned in time. The output of the fast edge source is used as the synchronized
jitter, en
trigger source. The output of the fast edge source is split and connected to the Channel 2 input of both the parent and child
instruments.
Equipment setup
External
To minimize any differences that may exist between the sampling clocks of the two instruments, the external reference clock
of the parent is fed to the child instrument. The REF OUT is connected to the REF IN of the child instrument. Select the
High (Tracking) option in the external reference menu of the child instrument.
NOTE. You must perform signal path compensation whenever you change the reference clock setting.
reference clock source
Dual O scilloscope Synchronization Kit Instructions 5
Deskew procedur
e
Deskew procedure
Deskewing the two instruments ensures that synchronization of ≤2 ps RMS is attained between channels on both instruments.
Instruments are aligned to a common point in time (the trigger source of the parent instrument) by applying a small time
offset (as needed, typically a few picoseconds) to each channel of the parent and child instruments, so that the acquisitions
are more closely aligned in time than they would be if we just used the hardware setup alone. The deskew procedure is
necessary as part of a full synchronization operation, and should be performed if your setup has changed in any way.
Connection procedure
Figure 3: Connections for deskewing the instruments
1. Using the set of four 12 inch (30 cm) matched SMA cables, connect one cable to CH1 of the parent, and connect the
other end to an open port on your 4-way power divider. Use one of the other open cables in this set to connect from
CH3 on the parent, to an open port on the 4-way divider.
2. Connect one of the remaining unattached cables of the set of four 12 inch matched SMA cables to CH1 of the child, and
the other end to an open port on your 4-way power divider. The remaining cable in this set of four will connect from
CH3 on the child, to an open port on the 4-way divider
6 Dual Oscilloscope Synchronization Kit Instructions
Deskew procedur
3. Using the pair of 12 inch (30 cm) matched SMA cables, connect one cable to CH2 of the parent, and the other end to
an open port of y
port of the 2-way divider.
4. Using one cable of the pair of 12 inch (30 cm) unmatched SMA cables, connect the last open port on your 2-way divider
to one of the negative outputs on the fast edge source/deskew fixture.
our 2-way power divider. The other cable in this pair will connect from CH2 on the child, to an open
e
5. Connect the remaining cable of the pair of 12 inch unmatched
divider and a
6. Connect an ex
from the front of the parent can be connected to CH4 for deskew operations.
7. Attach one end of your 20 inch (51 cm) BNC cable to the REF OUT on the parent, and the opposite end of the cable to
the REF IN on the child.
8. Attach the SMA-BNC adapter to AUX OUT of the parent; connect one end of the 60 inch (152 cm) SMA cable to the
adapter, a
9. Connect th
Refer to th
After com
one automated, the other manual.
ttach the other end to the second negative output on the fast edge source/deskew fixture.
ternal trigger signal to CH4 of the parent. If no external trigger source is available, the FAST EDGE output
nd connect the opposite end of cable to the trigger input on the front of the fast edge source power input.
e USB cable to any open USB type A port on the parent, and the type B c onnector to the fast edge source.
e figure (See Figure 3 on page 6.) to see how the equipment is connected.
pletion of the connection procedure, perform the deskew procedure. There are two possible deskew procedures,
Deskew procedure (automated)
1. If your oscilloscopes are not already connected to a network, connect them to each other using an Ethernet cable.
2. Open the Dual Scope Synchronization application located at Start > All Programs > Tektronix.
3. In the Instrument Connections section (See Figure 4.) of the Configure tab, enter the IP addresses for both the parent
and the child into the text boxes on the left side of the application window.
SMA cables to the last open port on your 4-way power
NOTE. The oscilloscope that you are running the application on becomes the parent. The application will connect through
the Virtual GPIB connection to the oscilloscope software on the parent.
To easily get the IP addresses of the instruments, you can hover-over the LAN Server Control icon in the system tray (See
Figure 5.) and see the current IP address of the oscilloscope as assigned by the network.
4. Press Connect. The oscilloscopes should report back with identity information in the console readout at the bottom
of the application.
Dual O scilloscope Synchronization Kit Instructions 7
Deskew procedur
Figure 4: Configure tab view upon initial application startup
e
Figure 5: Easily find the IP address of the oscilloscope from the L AN Server Control icon in the system tray
5. The source of the oscilloscopes external reference clocks is configurable in this application using the Ext. Ref Clock
check box. This check box lets you decide whether the oscilloscope is configured so that:
The parent external reference out is connected to the child external reference in (check box unchecked, default
condition)
Both the parent and child oscilloscopes are receiving a reference clock from an external source that is split and
connected to the reference in on both oscilloscopes (check box checked)
6. Once the oscilloscopes are connected, press the Auto-Config Scope button to set up the instruments for the automated
deskew routine.
The auto-config routine will set up the oscilloscopes with instrument settings based on the Deskew configuration
shown in the Schematics tab (See Figure 6.).
When this setup is complete, you will see an Autoscale Complete message in the console window at the bottom
of the application.
8 Dual Oscilloscope Synchronization Kit Instructions
Deskew procedur
e
Figure 6: Schematics tab, showing instrument connections for Deskew and Acquire operations
7. When the automated configuration completes, run the deskew routine.
The Num. Acq text box allows you to control how many acquisitions are taken. These acquisitions are used as a
statistical basis for the deskew values that are applied to the parent and child inputs.
The recommended minimum for Num. Acq is 100. Note: Tests have shown, negligible improvement with a setting
beyond 200 acquisitions.
Pressing the Deskew Channels button starts the deskew operation.
8. During the deskew operation, you will see a message displayed on both instruments indicating the progress of the
operation.
9. When deskew completes, you will see the Deskew Incomplete message, in the lower right-hand side of the application,
change to Deskew Complete.
After deskew is applied to the system, you can disconnect the 4-way divider from the system, and apply your data signals
to the oscilloscopes as shown in the Acquire Configuration under the Schematics tab.
Dual O scilloscope Synchronization Kit Instructions 9
Deskew procedur
Using the Dual Scope Synchronization software for instrument operation after deskew
Adjust the vertical and horizontal scaling on the instruments as needed, within the following guidelines:
The sample rate of the instruments must not be changed after the deskew operation has been performed.
To control the acquisition state of both instruments, you only need to use the parent front panel.
The child unit is left in Run mode, and will respond to the parent Run/Stop and Single buttons.
The Dual Scope Synchronization application has a minimized interface that allows you to better see the oscilloscope graticule,
and still perform most of the main functions available in the program. Pressing the Compact View button in the main window
will minimize the application (See Figure 7.). Pressing the Restore button returns the application to the original (default) size.
Figure 7: Minimized application window
e
Deskew procedure (manual)
If the Dual Scope Synchronization application is not used, the channels on the two synchronized oscilloscopes can also be
deskewed manually. The steps listed in this section guide you through the manual deskew process.
Configure the following oscilloscope settings:
1. Set Vertical Scale of CH1 and CH3 on both the parent and child to 20 mV/div.
Go into the Vertical menu, and select Vertical Setup.
Select the CH1 tab and use the S cale control to change the scale of CH1 to 20 mV.
Adjust the Position to 4divusing the position selection just above the scale setting.
Repeat these steps for CH3 on the parent, and for CH1 and CH3 on the child.
2. Set scale of CH2 on parent and child to 40mV/div.
Go into the Vertical menu, and select Vertical Setup.
Select the CH2 tab and use the S cale control to change the scale of CH2 to 40 mV.
Adjust the Position to 4divusing the position selection just above the scale setting.
Repeat for CH2 on the child.
3. Set 100 GS/s sampling rate on the parent and the child.
Go into the Horiz/Acq menu, and select Horizontal/Acquisition Setup.
Set Horizontal Mode to manual.
Set Sample Rate to 100 GS/s.
Repeat for the child.
10 Dual Oscilloscope Synchronization Kit Instructions
4. Setup the A Trigger on the parent.
Go into Trig>A Event (Main) Trigger Setup. and select the A Event tab
Deskew procedur
e
Select Edge from the Trigger Type pul
Select CH4 in the Source pull-down, and press the S et to 50% button.
5. In the A>B Seq tab, you select the Trig on nth Event button, and then set the B Event field value to 1.
6. Setup the B Trigger on the parent.
Turn on CH2
Go to the tab labeled B Event and select Edge for the Trigger Type, and CH2 for the source. Adjust B Event trigger
level to mid-point of the signal present on CH2, which should be approximately –60 mV. Turn off CH2.
7. Select the Options tab and ensure the Normal button is active under the Trigger Mode heading. Uncheck Enhanced
Triggering from the section labeled Trigger Position. Now, select the H oldoff Time button, adjusting the Trig. Holdoff
field to 50 ms.
8. Set the child instrument to trigger on an single A Event trigger with CH 2 as the source.
9. Set up the A Trigger on the child to trigger on CH2, by going into Trig>A Event (Main) Trigger Setup, and in the A
Event tab select Trigger Type Edge.
10. Now select CH2 in the Source pull-down, and set the trigger level to -160 mV.
11. Select the Options tab and ensure Normal button is active under the Trigger Mode heading, then uncheck Trigger
Position Enhanced Triggering.
12. Configure the child to accept an external reference.
Select Utilities from the top menu, then External Signals.
l-down.
Choose External for the reference source.
Set PLL Loop Bandwidth setting to High (Tracking).
13. Configure AUX OUT on the parent oscilloscope.
Select Utilities from the top menu, then External Signals.
Set the AUX OUT to ATrig.
Set polarity to Neg.
14. Turn on Zoom for both parent and child.
In the Horiz/Acq menu, select Zoom Controls and then select the Display button.
Adjust the horizontal position of the zoom window to 50% (middle of acquisition).
Set the zoom factor to 100.
15. Turn on Infinite Persistence for the parent and the child.
Go into the Display menu and select Display Setup.
In the Appearance tab, select Persistence Variable.
Under the Intensity section of the Appearance tab, adjust the Record View value to 35-40%.
In the Colors tab, set the Record View Palette to Te mp.
Dual O scilloscope Synchronization Kit Instructions 11
Deskew procedur
Apply deskew to channels
Adjust the deskew for both parent and child:
In the Vertical menu, select Deskew from the menu listing.
In the window that pops up, select CH1 and adjust deskew until you reach the point where the center of the persisted
waveform trace is lined up with the horizontal trigger position; this is indicated by the orange triangle at the top edge of
the waveform display area.
Apply deskew for CH3 on the parent, and CH1 and CH3 on the child in the same way as you did for CH1 of the parent.
e
12 Dual Oscilloscope Synchronization Kit Instructions
Acquisition procedure
This procedure assumes you have just completed the deskew procedure.
Connection procedure
Acquisition pro
cedure
Figure 8: Connections to acquire waveforms
1. Remo
2. Disconnect the two pairs of 12 inch matched delay SMA cables from the four-way divider. Use these four cables to
3. Disconnect the cable on the FAST EDGE output of the parent instrument. Connect the open end of the cable to your
Re
Af
Dual O scilloscope Synchronization Kit Instructions 13
ve the 12 inch (30 cm) SMA cable that goes from the negative output of the fast edge source to the four-way
SMA power divider.
connect to the signals to be acquired.
gger signal.
tri
fer to the figure (See Figure 8.) to see how the equipment is connected.
ter completion of the connection procedure, you’re ready to acquire your signals.
Conclusion
Conclusion
Once you complete the actions discussed in this document, you have two instruments that are synchronized in time, to within
≤2 ps RMS between instrument channels on the two instruments.
14 Dual Oscilloscope Synchronization Kit Instructions
Appendix A
067-2431-xx Deskew Fixture
Product description
Appendix A
The fast edge
edge source to time-align (deskew) signals at the inputs of P7600 Series probes. It allows you to deskew the probes
when you are using P76CA-xxx probe adapters with coax cables or the P76TA solder tip adapter with P7500 Series
TriMode Pro
The edge signal input voltage is adjustable to accommodate different logic levels, and is provided by the oscilloscope FAST
EDGE output or by an external source. The edge signal input voltage must be between –2 and +5 volts, with a 1 ns
or faster rise time.
Internal circuitry conditions the input signal to between –1.5 and +4 volts, with a rise time of 40 ps. The fixture is powered
by one of the USB ports of the oscilloscope.
Connectors on the fixture accept the coax adapters and solder tips that are available for the P7600 series probes.
source can also be used as a probe deskew fixture. When used as a probe deskew fixture, it provides an
be solder tips.
NOTE. You cannot deskew probes with coax connectors to probes with solder tips; only coax-to-coax or tip-to-tip probes
can be deskewed together.
CAUTION. The deskew fixture is ESD sensitive. To avoid damaging the fixture, only use it at an antistatic workstation
and observe proper ESD practices.
Overview
For best pe
probe manual for detailed instructions for performing the DC Probe Calibration Procedure.
You should also check the calibration status of the probes that you intend to use prior to performing the deskew procedure.
Use the procedure below.
Dual O scilloscope Synchronization Kit Instructions 15
rformance, you s hould do the DC Calibration procedure before performing the Deskew procedure. Refer to your
Appendix A
Check the Calibration Status.
1. Select Probe Cal... from the Vertical menu.
2. Select the channel to which the probe is attached and then check the Probe Status readout. This readout can show
one of the following values:
Initialized. The probe has not been calibrated on the selected channel; perform the DC probe calibration procedure.
Compensated. The probe has been calibrated on the selected channel.
Fail. The probe has not been calibrated; repeat the procedure.
If the test continues to fail, troubleshoot the problem; do not continue with the deskew procedure.
Deskew Procedure. The deskew function compensates for signal delays that occur between probes due to differences
in tips or cable lengths. The oscilloscope deskew feature applies deskew v alues after it completes each acquisition. The
deskew val
ues do not affect logic triggering. Deskew has no affect on XY and XYZ display formats.
1. Connect the deskew fi xture to a USB power source. The power LED lights and the solder tip retainer clips illuminate.
2. Connect the probes to the oscilloscope.
3. Connect the probes to the fixture, using the connectors that match your probe. Leave the 50 Ω terminations on any
unused SMA connectors.
Connect the P76CA–292 or P76CA–292C coax adapters to the SMA connectors on the fixture.
Connect the P76CA–SMP coax adapters to SMP-to-SMA adapters, and then to the SMA connectors on the fixture.
Attach the P76TA probe solder tip adapter with P7500 Series TriMode Probe solder tips beneath the spring-loaded
ainers on the fixture. LEDs with adjustable brightness help you align the probe tip leads to the fixture contacts.
ret
See figure below.
NOTE. If you are deskewing probes with solder tips, use the same solder tips with the deskew fixture that you
ll use to take measurements.
wi
16 Dual Oscilloscope Synchronization Kit Instructions
NOTE. You cannot deskew probes with coax connectors to probes with solder tips; only coax-to-coax or tip-to-tip
probes can be de
skewed together.
Appendix A
4. Connect the edge signal input to the fixture. Use either the FAST EDGE output on the oscilloscope, or connect an
external source. The external signal source voltage must be between –2 and +5 volts, with a 1 ns or faster rise time.
CAUTION. Do not exceed the input voltage limits of the fixture. Damage to the fixture and probes may result.
5. Connect a DMM or oscilloscope to the threshold level monitor pins.
Dual O scilloscope Synchronization Kit Instructions 17
Appendix A
6. Using an insulated tool, adjust the threshold level on the fixture to the appropriate logic level (for example, 1.4 V for
TTL circuits).
7. Select a refer
depending on your setup.
8. Select Deskew from the Vertical menu.
9. Select Channel 1 and set the Deskew to 0.0 s.
10. Display all channels to deskew, including the reference channel.
11. Set the Display Persistence to Infinite Persistence mode.
12. Set the Record View Palette to Temperature Grading.
13. Adjust the trigger level to get a stable trigger.
14. Adjust the vertical SCALE, POSITION, and OFFSET for each channel so that the signals overlap and are centered on
screen. Make sure all channels being deskewed are at the same volts/div setting. Deskew the channels at the same
level as yo
15. Adjust the
16. Adjust th
17. Adjust th
18. Select De
19. Select o
ence channel with which all other channels will be deskewed. This is typically Channel 1, but can vary
ur planned signal measurement.
horizontal POSITION so that a triggered rising edge of the reference channel is at center screen.
e horizontal SCALE so the differences in the channel delays are clearly visible.
e horizontal POSITION again so that the first rising edge of the reference channel is at center screen.
skew from the Vertical menu.
ne of the channels to match to the reference channel.
NOTE. Do the next step at a signal amplitude within the same attenuator range (vertical scale) as your planned signal
measurements. Any change to the vertical s cale after the deskew is complete can change the attenuator setting and give
tly different signal path. This signal path difference can cause as high as 100 ps variation in timing skew between
a sligh
channels.
20. Adjus
21. Repea
t the deskew time for that channel so that its signal aligns with that of the reference channel.
t steps 19 and 20 for each additional channel that you want to deskew.
Equipment Recycling. This product complies with the European Union’s requirements
ding to Directive 2002/96/EC on waste electrical and electronic equipment (WEEE).
accor
For more information about recycling options, check the Support/S ervice section of the
Tektronix Web site (www.tektronix.com).
18 Dual Oscilloscope Synchronization Kit Instructions
Contacting Tektronix
Web site: www.tektronix.com
Phone: 1-800-833-92
Address: Tektronix, Inc.
Department or
14200 SW Karl Braun Drive
P.O. Box 500
Beaverton, O
Email:
techsuppor
00
name (if known)
R 97077 USA
t@tektronix.com
Warranty Information
For warranty information, go to www.tektronix.com/warranty.
Appendix A
Dual O scilloscope Synchronization Kit Instructions 19
Appendix A
20 Dual Oscilloscope Synchronization Kit Instructions
Index
Index
A
Acquisition p
rocedure, 13
connection procedure, 13
C
Connector torque, 4
D
Deskew, 1
Deskew fixture, 15
Deskew procedure, 6
apply to ch
automated, 7
connection procedure, 6
manual, 1
Documentation, v
annels, 12
0
E
Equipment lis
Equipment setup, 5
External reference
source, 5
External trigger, 4
t, 2
I
Instrument connections, 5
Introduct
ion, 1
R
Recommended equipment, 2
Reference clock
source, 5
Related documentation, v
S
Safety Summary, iii
Signal path compensation, 3
Synchroniza
tion, 1
methods, 1
T
Trigger source, 5
Dual O scilloscope Synchronization Kit Instructions 21
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