LE160 & LE320 Linear Equalizer
Product Specifications & Performance Verification
Technical Reference Manual
Warning
The servicing instructions are for use by qualified personnel only.
To avoid personal injury, do not perform any servicing unless you
are qualified to do so. Refer to all safety summaries prior to
performing service.
Supports LE160 & LE320 Product Firmware V1.0 and above
*P077088400*
077-0884-00
Copyright © Tektronix. All rights reserved. Licensed software products are owned by Tektronix or its subsidiaries
or suppliers, and are protected by national copyright laws and international treaty provisions. Tektronix products
are covered by U.S. and foreign patents, issued and pending. Information in this publication supersedes that in all
previously published material. Specifications and price change privileges reserved.
TEKTRONIX and TEK are registered trademarks of Tektronix, Inc.
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 one
(1) year from the date of shipment. If any such product proves defective during this 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 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 the return of the product to Customer if the shipment is to a
location within the country in which the Tektronix service center is 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 attempts 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
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
VENDOR HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES.
[W2 – 15AUG04]
Table of Contents
Important safety information .............................................................................................................. iii
General safety summary ................................................................................................................ iii
Service safety summary .................................................................................................................. v
Terms in the manual ...................................................................................................................... vi
Terms on the product ..................................................................................................................... vi
Symbols on the product ................................................................................................................. vi
Compliance Information .................................................................................................................... vii
EMC compliance .......................................................................................................................... vii
Safety compliance ....................................................................................................................... viii
Environmental compliance ............................................................................................................ ix
Preface
Related documentation ................................................................................................................... 1
Specifications
Data input (single-ended) ............................................................................................................... 3
Data output (differential) ................................................................................................................ 4
Physical characteristics ................................................................................................................... 5
Environmental characteristics ......................................................................................................... 5
Performance verification
Prerequisites .................................................................................................................................... 7
Functional checks ........................................................................................................................... 7
Required equipment .................................................................................................................. 8
Functional setups ....................................................................................................................... 8
Functional check procedure ..................................................................................................... 10
Warranted characteristics tests ..................................................................................................... 12
Warm up information .............................................................................................................. 12
Check the skew between DP and DN ...................................................................................... 12
Test record
LE160 & LE320 Specifications & Performance Verification i
Table of Contents
ii LE160 & LE320 Specifications & Performance Verification
Important safety information
This manual contains information and warnings that must be followed by the user
for safe operation and to keep the product in a safe condition.
To safely perform service on this product, see the Service safety summary that
follows the General safety summary.
General safety summary
Use the product only as specified. Review the following safety precautions to
avoid injury and prevent damage to this product or any products connected to it.
Carefully read all instructions. Retain these instructions for future reference.
Comply with local and national safety codes.
For correct and safe operation of the product, it is essential that you follow
generally accepted safety procedures in addition to the safety precautions
specified in this manual.
The product is designed to be used by trained personnel only.
Only qualified personnel who are aware of the hazards involved should remove
the cover for repair, maintenance, or adjustment.
This product is not intended for detection of hazardous voltages.
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.
When incorporating this equipment into a system, the safety of that system is the
responsibility of the assembler of the system.
LE160 & LE320 Specifications & Performance Verification iii
Important safety information
To avoid fire or personal
injury
Use proper power cord. Use only the power cord specified for this product and
certified for the country of use. Do not use the provided power cord for other
products.
Ground the product. This product is grounded through the grounding conductor of
the power cord. To avoid electric shock, the grounding conductor must be
connected to earth ground. Before making connections to the input or output
terminals of the product, ensure that the product is properly grounded. Do not
disable the power cord grounding connection.
Power disconnect. The power cord disconnects the product from the power
source. See instructions for the location. Do not position the equipment so that it
is difficult to disconnect the power cord; it must remain accessible to the user at
all times to allow for quick disconnection if needed.
Use proper AC adapter. Use only the AC adapter specified for this product.
Observe all terminal ratings. To avoid fire or shock hazard, observe all rating and
markings on the product. Consult the product manual for further ratings
information before making connections to the product.
Do not apply a potential to any terminal, including the common terminal, that
exceeds the maximum rating of that terminal.
Do not float the common terminal above the rated voltage for that terminal.
The measurement terminals on this product are not rated for connection to mains
or Category II, III, or IV circuits.
Do not operate with suspected failures. If you suspect that there is damage to this
product, have it inspected by qualified service personnel.
Disable the product if it is damaged. Do not use the product if it is damaged or
operates incorrectly. If in doubt about safety of the product, turn it off and
disconnect the power cord. Clearly mark the product to prevent its further
operation.
Examine the exterior of the product before you use it. Look for cracks or missing
pieces.
Use only specified replacement parts.
Use proper fuse. Use only the fuse type and rating specified for this product.
Wear eye protection. Wear eye protection if exposure to high-intensity rays or
laser radiation exists.
Do not operate in wet/damp conditions. Be aware that condensation may occur if a
unit is moved from a cold to a warm environment.
Do not operate in an explosive atmosphere.
Keep product surfaces clean and dry. Remove the input signals before you clean
the product.
Provide proper ventilation. Refer to the manual's installation instructions for
details on installing the product so it has proper ventilation.
Slots and openings are provided for ventilation and should never be covered or
otherwise obstructed. Do not push objects into any of the openings.
iv LE160 & LE320 Specifications & Performance Verification
Important safety information
Provide a safe working environment. Always place the product in a location
convenient for viewing the display and indicators.
Avoid improper or prolonged use of keyboards, pointers, and button pads.
Improper or prolonged keyboard or pointer use may result in serious injury.
Be sure your work area meets applicable ergonomic standards. Consult with an
ergonomics professional to avoid stress injuries.
Service safety summary
The Service safety summary section contains additional information required to
safely perform service on the product. Only qualified personnel should perform
service procedures. Read this Service safety summary and the General safety
summary before performing any service procedures.
To avoid electric shock. Do not touch exposed connections.
Do not service alone. Do not perform internal service or adjustments of this
product unless another person capable of rendering first aid and resuscitation is
present.
Disconnect power. To avoid electric shock, switch off the product power and
disconnect the power cord from the mains power before removing any covers or
panels, or opening the case for servicing.
Use care when servicing with power on. Dangerous voltages or currents may exist
in this product. Disconnect power, remove battery (if applicable), and disconnect
test leads before removing protective panels, soldering, or replacing components.
Verify safety after repair. Always recheck ground continuity and mains dielectric
strength after performing a repair.
LE160 & LE320 Specifications & Performance Verification v
Important safety information
Terms in the manual
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.
Terms on the product
These terms may appear on the product:
■
DANGER indicates an injury hazard immediately accessible as you read the
marking.
Symbols on the product
■
WARNING indicates an injury hazard not immediately accessible as you
read the marking.
■
CAUTION indicates a hazard to property including the product.
When this symbol is marked on the product, be sure to consult the
manual to find out the nature of the potential hazards and any actions
which have to be taken to avoid them. (This symbol may also be used
to refer the user to ratings in the manual.)
The following symbols may appear on the product:
vi LE160 & LE320 Specifications & Performance Verification
Compliance Information
This section lists the EMC (electromagnetic compliance), safety, and
environmental standards with which the instrument complies.
EMC compliance
EC Declaration of
Conformity – EMC
Meets intent of Directive 2004/108/EC for Electromagnetic Compatibility.
Compliance was demonstrated to the following specifications as listed in the
Official Journal of the European Communities:
EN 61326-1 2006 . EMC requirements for electrical equipment for measurement,
control, and laboratory use.
■
CISPR 11:2003. Radiated and conducted emissions, Group 1, Class A
■
IEC 61000-4-2:2001. Electrostatic discharge immunity
■
IEC 61000-4-3:2002. RF electromagnetic field immunity
■
IEC 61000-4-4:2004. Electrical fast transient / burst immunity
■
IEC 61000-4-5:2001. Power line surge immunity
■
IEC 61000-4-6:2003. Conducted RF immunity
■
IEC 61000-4-11:2004. Voltage dips and interruptions immunity
1
2
3
EN 61000-3-2:2006. AC power line harmonic emissions
EN 61000-3-3:1995. Voltage changes, fluctuations, and flicker
European contact.
Tektronix UK, Ltd.
Western Peninsula
Western Road
Bracknell, RG12 1RF
United Kingdom
1
This product is intended for use in nonresidential areas only. Use in residential areas may cause electromagnetic interference.
2
Emissions which exceed the levels required by this standard may occur when this equipment is connected to a test object.
3
For compliance with the EMC standards listed here, high quality shielded interface cables should be used.
LE160 & LE320 Specifications & Performance Verification vii
Compliance Information
Australia / New Zealand
Declaration of Conformity
– EMC
Safety compliance
Equipment type
Safety class
Complies with the EMC provision of the Radiocommunications Act per the
following standard, in accordance with ACMA:
■
CISPR 11:2003. Radiated and conducted emissions, Group 1, Class A, in
accordance with EN 61326- 1:2006.
Australia / New Zealand contact.
Baker & McKenzie
Level 27, AMP Centre
50 Bridge Street
Sydney NSW 2000, Australia
This section lists safety and compliance information.
Test and measuring equipment.
Class 1 – grounded product.
Pollution degree
description
A measure of the contaminants that could occur in the environment around and
within a product. Typically the internal environment inside a product is
considered to be the same as the external. Products should be used only in the
environment for which they are rated.
■
Pollution Degree 1. No pollution or only dry, nonconductive pollution
occurs. Products in this category are generally encapsulated, hermetically
sealed, or located in clean rooms.
■
Pollution Degree 2. Normally only dry, nonconductive pollution occurs.
Occasionally a temporary conductivity that is caused by condensation must
be expected. This location is a typical office/home environment. Temporary
condensation occurs only when the product is out of service.
■
Pollution Degree 3. Conductive pollution, or dry, nonconductive pollution
that becomes conductive due to condensation. These are sheltered locations
where neither temperature nor humidity is controlled. The area is protected
from direct sunshine, rain, or direct wind.
■
Pollution Degree 4. Pollution that generates persistent conductivity through
conductive dust, rain, or snow. Typical outdoor locations.
viii LE160 & LE320 Specifications & Performance Verification
Compliance Information
Pollution degree
Measurement and
overvoltage category
descriptions
Mains overvoltage
category rating
Pollution Degree 2 (as defined in IEC 61010-1). Note: Rated for indoor, dry
location use only.
Measurement terminals on this product may be rated for measuring mains
voltages from one or more of the following categories (see specific ratings
marked on the product and in the manual).
■
Measurement Category II. For measurements performed on circuits directly
connected to the low-voltage installation.
■
Measurement Category III. For measurements performed in the building
installation.
■
Measurement Category IV. For measurements performed at the source of
low-voltage installation.
Overvoltage Category II (as defined in IEC 61010-1)
Environmental compliance
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 recycling. Production of this equipment required the extraction and use
of natural 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 resources, we encourage you to recycle this
product in an appropriate system that will ensure that most of the materials are
reused or recycled appropriately.
This symbol indicates that this product complies with the applicable
European Union requirements according 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
(www.tektronix.com).
Restriction of hazardous
substances
LE160 & LE320 Specifications & Performance Verification ix
This product is classified as an industrial monitoring and control instrument, and
is not required to comply with the substance restrictions of the recast RoHS
Directive 2011/65/EU until July 22, 2017.
Compliance Information
x LE160 & LE320 Specifications & Performance Verification
Preface
Related documentation
This document lists the product specifications and provides procedures to verify
instrument performance.
The following documentation is available to support your linear equalizer
product. The documents can be downloaded from the Tektronix Web site at
www.tektronix.com/manuals.
■
LE160 & LE320 Quick Reference Installation Instructions (Tektronix part
number, 071-3222-xx). Printed instructions shipped with each instrument
providing high-level installation information.
■
LE160 & LE320 Linear Equalizer Instruction Manual (Tektronix part
number, 077-0883-xx). PDF-only. This document provides high-level
information for using and maintaining the linear equalizer.
■
LE160 & LE320 Linear Equalizer Declassification & Security Instructions
(Tektronix part number, 077-0882-xx). PDF only. Use these instructions to
declassify or sanitize your instrument.
LE160 & LE320 Specifications & Performance Verification 1
Preface
2 LE160 & LE320 Specifications & Performance Verification
Specifications
This chapter contains specifications for the instrument. All specifications are
guaranteed unless noted as "typical." Typical specifications are provided for your
convenience but are not guaranteed. Specifications that are marked with the
symbol are checked in Performance Verification.
All specifications apply to all models unless noted otherwise. To meet
specifications, two conditions must first be met:
■
■
For optimum performance using an external oscilloscope, please consult the
documentation for any external oscilloscopes used with your Tektronix linear
equalizer to determine the warm-up period and signal-path compensation
requirements.
Data input (single-ended)
The instrument must be in an environment with temperature, altitude,
humidity, and vibration within the operating limits described in these
specifications.
The instrument must have had a warm-up period of at least 30 minutes.
Number of taps 4 standard, 9 with Option 9T
Operating data rate range LE160, 4 Gb/s to 21 Gb/s
LE320, 8 Gb/s to 32 Gb/s
Coupling AC coupled
Maximum data input level 800 mv
operation. Not the input damage level.
Data input sensitivity 40 mV
The minimum input signal level acceptable to the data input for proper operation
Data input termination 100 Ω differential
50 Ω single-ended
Connector type 2.92 mm female
Input return loss (typical)
(typical) The maximum input signal level acceptable to the data input for proper
p-p
, (typical)
p-p
1
1
Operation down to 8 Gbps is supported with single tap response.
LE160 & LE320 Specifications & Performance Verification 3
Specifications Data input (single-ended) (cont.)
LE160 10 dB RL 0.2 to 7 GHz
5 dB RL > 7 GHz to 30 GHz
LE320 10 dB RL 0.2 to 7 GHz
5 dB RL > 7 GHz to 30 GHz
Data output (differential)
Minimum settable amplitude range
(DP/DN)
0 mV
to 2000 mV
p-p
maximum differential
p-p
Pattern: 1100, taps set for flat loss
Settable amplitude resolution 0.15 dB (typical)
Coupling AC coupled
Skew between DP and DN <2 ps (typical), 4 ps (specified), taps set for flat frequency response
Additive random jitter
LE160 220 fs
LE320 300 fs
(typical), input pattern 1100
RMS
(typical), input pattern 1100
RMS
2
2
Tap range -100 to +100 tap settings
Connector type 2.92 mm, female
Zero output state timing constant ±600 mV, single ended signaling level to 0 V ±10 mV in ≤ 40 UI = 2.9 ns; idle state (fall time after
enable asserted)
Time constant is based on 14 Gb SAS, fibre channel and PCIe Gen4. Timing from full output to
0 V. Hold at 0 for 2 ms minimum, then return to enable. Rise time expectation is on order of 30 to
40 ps. Latency of blanking period start is not timed to anything else.
Consecutive run length amplitude
droop
<10 % maximum droop (typical)
PCIe 16 Gb standard calibration pattern: 128 bit 1, 128 bit 0, single-ended, compared to
1100 pattern amplitude
2
Additive Jitter. The LE320/LE160 can be configured to many conditions resulting in increased Data Dependent Jitter (DDJ) and Random Jitter (Rj), for
example in a backplane emulation configuration. The LE320 can be tuned to have < 300 fs RJ RMS and < 6 ps of DDJ.
4 LE160 & LE320 Specifications & Performance Verification
Specifications
Physical characteristics
Dimensions are with bumpers attached.
Height 4.01 cm (1.58 in.)
Width 12.62 cm (4.97 in.)
Depth 9.02 cm (3.55 in.)
Weight 0.34 kg (12 oz.)
Environmental characteristics
Temperature
Operating 0 °C to +50 °C (32 °F to 122 °F)
Nonoperating -40 °C to +71 °C ( -40 °F to 159.8 °F) with 15 C/hour maximum gradient
Humidity
Operating 5% to 95% relative humidity (% RH) up to +30 °C
5% to 45% RH above 30 °C up to 50 °C, non-condensing
Nonoperating 5% to 95% relative humidity (% RH) up to +30 °C
5% to 45% RH above 30 °C up to 50 °C, non-condensing
Altitude
Operating Up to 3000 m (9842 ft.)
Derate maximum operating temperature by 1 °C per 300 m above 1500 m altitude.
Nonoperating Up to 12,000 m (39,370 ft.)
LE160 & LE320 Specifications & Performance Verification 5
Specifications Physical characteristics (cont.)
6 LE160 & LE320 Specifications & Performance Verification
Performance verification
This section describes the procedures to verify the performance of your
instrument. Performance verification procedures confirm that a product meets or
exceeds the performance requirements for the published specifications
documented in the Specifications chapter of this manual. The performance
verification procedures certify the accuracy of an instrument and provide a
traceability path to national standards.
NOTE. The performance verification procedure is not a calibration procedure.
The performance verification procedure only verifies that your instrument meets
key specifications. For your instrument to be calibrated, it must be returned to a
Tektronix service facility.
Prerequisites
The tests in this section make up an extensive, valid confirmation of performance
and functionality when the following requirements are met:
■
The linear equalizer and other test equipment used in these procedures must
have been operating for a warm-up period of at least 20 minutes after starting
the LE application and power applied to the linear equalizer.
Functional checks
■
The linear equalizer must be operating at a stable ambient temperature.
■
No error messages are displayed in the user interface.
This section describes procedures to verify that the instrument is functional, but
might not meet the advertised performance specifications.
LE160 & LE320 Specifications & Performance Verification 7
Performance verification
Required equipment
The following table lists the required equipment to perform the functional checks.
Equipment Minimum
requirements
Pattern generator Bit rate ≥ 16 Gb/s
Rise/fall time ≤ 20 ps
20% to 80%
≥800 mV
Pattern: 1010
Sampling oscilloscope 50 GHz minimum
bandwidth
Phase-matched cable
set
6 in. coaxial cable 2.92 mm, flex K-male to
2.92 mm, <2 ps
matching, I m
maximum
K-male
P-P
Example Purpose
Tektronix BSA175,
BSA286C, or
equivalent
Tektronix DSA8300
with 80E108 or 80E11
modules installed, or
equivalent
Tektronix pn
(174-5969-00),
standard part of LE160/
LE320
Tektronix pn
(174-6362-00),
standard part of LE160/
LE320
Apply a test signal to
the linear equalizer
Check rise time and
signal fidelity
Functional setups
Complete the functional setups before proceeding with the Warranted
Characteristic tests.
8 LE160 & LE320 Specifications & Performance Verification
Performance verification
Use the following diagram to help set up the instrument connections.
Figure 1: Functional check equipment setup
1. If you have not done so, connect the USB cable from the linear equalizer to
the host PC.
2. Push the Power button on the linear equalizer and verify that the Power LED
turns on.
3. Make sure that the LE application is running on the host PC by verifying that
the linear equalizer connects to the PC through the graphical user interface.
4. Click the Connect tab at the top of the window.
5. Click the 4T tab to open the 4T window. The LE application should look
similar to the following figure.
LE160 & LE320 Specifications & Performance Verification 9
Performance verification
Figure 2: LE user interface
Functional check
procedure
6. Complete the other connections as shown in the illustration.
7. Allow all equipment to warm up for at least twenty minutes.
Verify that the equipment is set up properly as shown in the previous diagram
Figure 1: Functional check equipment setup on page 9.
1. Set up the pattern generator for a 16 Gbp/s 1010 waveform with a 800 mV
output.
2. Verify that the linear equalizer is set up as follows:
a. Click the Connect button in the user interface to connect the application
to the linear equalizer.
b. Select the 4T tab.
c. Enable Channel 1 on the linear equalizer and set the amplitude for
approximately 800 mV
output.
P-P
The Channel 1 button should be highlighted in green.
d. Adjust the Output Amplitude control on the linear equalizer to
800 mV
P-P
.
p-p
The LE display should look similar to the following figure.
10 LE160 & LE320 Specifications & Performance Verification
Figure 3: LE display with Channel 1 enabled
Performance verification
3. Set up the sampling oscilloscope as follows:
a. Connect the channel 1 oscilloscope out put to the Ch 1 + output of the
linear equalizer.
b. Connect the channel 2 oscilloscope out put to the Ch 1 - output of the
linear equalizer.
c. Set the vertical controls of the oscilloscope to 100 mV per division.
d. Set the horizontal controls of the oscilloscope to 10 ps per division.
e. Center the traces horizontally on the display as shown in the following
figure.
Figure 4: Sampling oscilloscope display
LE160 & LE320 Specifications & Performance Verification 11
Performance verification
Warranted characteristics tests
The following procedures in this section verify the LE160/LE320 performance is
within the warranted specifications.
Photocopy the test record at the end of this document and use it to record the
performance test results.
Warm up information
Check the skew between
DP and DN
Before continuing with this procedure ensure that all equipment has had a 20minute warm-up period.
This check verifies the skew between the DP and DN meets the published
specifications. Record the measurement results in the appropriate section in the
Test Record. (See Test record on page 15.)
1. Ensure that the instruments are connected and set up. (See Figure 1:
Functional check equipment setup.)
2. Set the pattern generator to output a 1010 pattern.
3. Enable the desired test channel on the linear equalizer and set the Output
Amplitude control to 800 mV
4. Check the Channel 1 skew between DP and DN:
a. Measure the positive crossing point on channel 1 of the oscilloscope.
Record the value in "Scope Ch 1 measurement", row A in the Test
Record.
b. Measure the negative crossing point on channel 2 of the oscilloscope.
Record the value in "Scope Ch 2 measurement", row B in the Test
Record.
P-P
.
c. Subtract the value from row A minus row B and enter in row C in the
Test Record.
d. Reverse the oscilloscope input cables at the output of the linear equalizer.
Oscilloscope Channel 1 should now be connected to the Ch 1 - output of
the linear equalizer and oscilloscope Channel 2 should be connected to
the Ch 1 + output of the linear equalizer.
e. Measure the negative crossing point on channel 1 of the oscilloscope.
Record the value in "Scope Ch 1 measurement", row D in the Test
Record.
f. Measure the positive crossing point on channel 2 of the oscilloscope.
Record the value in "Scope Ch 2 measurement", row E in the Test
Record.
g. Calculate the difference between the measurements in row D minus row
E. Record the difference in row F in the Test Record.
h. Calculate the difference between the entries in row C minus row F.
Divide that result by 2. Enter the divided value in row G.
12 LE160 & LE320 Specifications & Performance Verification
Performance verification
This is the skew between the Ch 1 DP and DN outputs of the linear
equalizer.
5. Check the Channel 2 skew between DP and DN:
a. Connect the channel 1 oscilloscope output to the Ch 2 + output of the
linear equalizer.
b. Connect the channel 2 oscilloscope output to the Ch 2 - output of the
linear equalizer.
c. Measure the positive crossing point on channel 1 of the oscilloscope.
Record the value in "Scope Ch 1 measurement", row H in the Test
Record.
d. Measure the negative crossing point on channel 2 of the oscilloscope.
Record the value in "Scope Ch 2 measurement", row I in the Test
Record.
e. Subtract the value from row A minus row B and enter in row J in the Test
Record.
f. Reverse the oscilloscope input cables at the output of the linear equalizer.
Oscilloscope Channel 1 should now be connected to the Ch 1 - output of
the linear equalizer and oscilloscope Channel 2 should be connected to
the Ch 1 + output of the linear equalizer.
g. Measure the negative crossing point on channel 1 of the oscilloscope.
Record the value in "Scope Ch 1 measurement", row K in the Test
Record.
h. Measure the positive crossing point on channel 2 of the oscilloscope.
Record the value in "Scope Ch 2 measurement", row L in the Test
Record.
i. Calculate the difference between the measurements in row D minus row
E. Record the difference in row M in the Test Record.
j. Calculate the difference between the entries in row J minus row M.
Divide that result by 2. Enter the divided value in row N.
This is the skew between the Ch 2 DP and DN outputs of the linear
equalizer.
6. Verify that the entries in rows G and N meet the specifications in the table
near the top of the Test Record.
LE160 & LE320 Specifications & Performance Verification 13
Performance verification
14 LE160 & LE320 Specifications & Performance Verification
Test record
Photocopy this page and use it to record the performance test results for your
instrument.
Table 1: LE160/LE320 test record
Instrument model number
Serial number
Verification performed by
Verification date
Characteristic Specification
Skew between DP and DN <4 ps, taps set for flat frequency response
Table 2: LE Channel 1 Worksheet test data
Characteristic Measurement Data
LE Ch 1 Measurement 1 A. Scope Ch 1 measurement
B. Scope Ch 2 measurement
C. Calculate: row A - row B
LE Ch 1 Measurement 2 - After
changing LE output cables
LE Ch 1 Skew between DP and DN G. Calculate: (row C - row F) / 2
D. Scope Ch 1 measurement
E. Scope Ch 2 measurement
F. Calculate: row D - row E
Table 3: LE Channel 2 Worksheet test data
Characteristic Measurement Data
LE Ch 2 Measurement 1 H. Scope Ch 1 measurement
I. Scope Ch 2 measurement
J. Calculate: row H - row I
LE Ch 2 Measurement 2 - After
changing LE output cables
LE Ch 2 Skew between DP and DN N. Calculate: (row J - row M) / 2
K. Scope Ch 1 measurement
L. Scope Ch 2 measurement
M. Calculate: row K - row L
LE160 & LE320 Specifications & Performance Verification 15
Test record
16 LE160 & LE320 Specifications & Performance Verification
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