Tektronix BERTScope
Clock Recovery Instruments
Quick Start User Manual
www.tektronix.com
0130-713-00
Tektronix BERTScope
Clock Recovery Instruments
CR125A, CR175A, CR286A
Quick Start User Manual
www.tektronix.com
0130-713-00
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, TEK, and BERTScope are registered trademarks of Tektronix, Inc.
FastFrame, OpenChoice, iView, iCapture, Pinpoint, RT-Eye, MyScope, TekLink, TekVPI, Error Location
Analysis, and MultiView Zoom are trademarks of Tektronix, Inc.
Contacting Tektronix
Tektronix, Inc.
14200 SW Karl Braun Drive
P.O. Box 500
Beaverton, OR U.S.A.
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
Warranty
All Tektronix CR125A, CR175A, and CR286A Clock Recovery Instruments are covered under the standard 1year product 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.
CR125A, CR175A, CR286A Clock Recovery Instruments Quick Start User Manual i
GeneralSafetySummary
General Safety Summary
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.
NOTE: 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.
Maintain Proper Grounding to avoid electrical shock.
WARNING
Use Proper Power Cord. Use only the power cord specified for this product and certified for the country of
use.
Connect and Disconnect Properly. Do not connect or disconnect probes or test leads while they are
connected to a voltage source.
No operator serviceable parts inside.
Do not remove cover.
Refer to qualified service personnel.
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.
Observe All Terminal Ratings. To avoid fire or shock hazard, observe all ratings and markings on the
product. Consult the product manual for further ratings information before making connections to the product.
Power Disconnect. The power cord disconnects the product from the power source. Do not block the power
cord; it must remain accessible to the user at all times.
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.
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
Do Not Operate in an Explosive Atmosphere
Keep Product Surfaces Clean and Dry
Provide Proper Ventilation. Refer to the manual's installation instructions for details on installing the
product so it has proper ventilation.
ii CR125A, CR175A, CR286A Clock Recovery Instruments Quick Start User Manual
GeneralSafetySummary
Terms in this Manual
These terms may appear in this manual:
WARNING.
or loss of life.
CAUTION.
to this product or other property.
NOTE.
modes, incorrect measurement results, or require resetting the instrument or personal
computers operating software interacting with it.
Warning statements identify conditions or practices that could result in injury
Caution statements identify conditions or practices that could result in damage
A notice statement identifies conditions which may result in unintended operating
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 marking.
CAUTION indicates a hazard to property including the product. The following symbols may appear on the
product:
CAUTION
CAUTION
To prevent damage to the instrument when the data outputs are not in use, terminate the data
outputs with the SMA terminations provided.
To prevent damage to the high sensitivity data circuitry, ensure that the input voltage does
not exceed ±5 V range, 3 V peak-peak.
CR125A, CR175A, CR286A Clock Recovery Instruments Quick Start User Manual iii
ComplianceInformation
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 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
IEC61000-4-2:2001. Electrostatic discharge immunity
IEC61000-4-3:2002. RF electromagnetic field immunity
IEC61000-4-4:2004. Electrical fast transient / burst immunity
IEC61000-4-5:2001. Power line surge immunity
IEC61000-4-6:2003. Conducted RF immunity
IEC61000-4-11:2004. Voltage dips and interruptions immunity
EN61000-3-2:2006. AC power line harmonic emissions
EN61000-3-3:1995. Voltage changes, fluctuations, and flicker
1, 2, 3
European Contact
Tektronix UK, Ltd.
Western Peninsula
Western Road
Bracknell, RG12 1RF
United Kingdom
Australia / New Zealand Declaration of Conformity–EMC
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 EN61326-
1:2006.
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
To ensure compliance with the EMC standards listed here, high quality shielded interface cables should be used.
iv CR125A, CR175A, CR286A Clock Recovery Instruments Quick Start User Manual
ComplianceInformation
Safety Compliance
EC Declaration of Conformity – Low Voltage
Compliance was demonstrated to the following specification as listed in the Official Journal of the European
Communities:
Low Voltage Directive 2006/95/EC
EN61010-1: 2001. Safety requirements for electrical equipment for measurement control and
laboratory use.
U.S. Nationally Recognized Testing Laboratory Listing
UL 61010-1:2004, 2nd Edition. Standard for electrical measuring and test equipment.
Canadian Certification
CAN/CSA-C22.2 No. 61010-1:2004. Safety requirements for electrical equipment for measurement,
control, and laboratory use. Part 1.
Additional Compliances
IEC 61010-1: 2001. Safety requirements for electrical equipment for measurement, control, and
laboratory use.
Equipment Type
Test and measuring equipment.
Safety Class
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.
Pollution Degree
Pollution Degree 2 (as defined in IEC61010-1). Note: Rated for indoor use only.
CR125A, CR175A, CR286A Clock Recovery Instruments Quick Start User Manual v
Compliance
Information
Installation (Overvoltage) Category Descriptions
Terminals on this product may have different installation (overvoltage) category designations. The installation
categories are:
Measurement Category IV. For measurements performed at the source of low-voltage installation.
Measurement Category III. For measurements performed in the building installation.
Measurement Category II. For measurements performed on circuits directly connected to the low-
voltage installation.
Measurement Category I. For measurements performed on circuits not directly connected to MAINS.
Overvoltage Category
Overvoltage Category II (as defined in IEC61010-1)
Environmental Considerations
Product End-of-Life Handling
Observe the following guidelines when recycling an instrument or component:
Equipment Recycling.
equipment may contain substances that could be harmful to the environment or human health if improperly
handled at the product’s end of life. In order 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.
Restriction of Hazardous Substances.
equipment, and is outside the scope of the 2002/95/EC RoHS Directive.
Production of this equipment required the extraction and use of natural resources. The
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 Website
(www.tektronix.com).
This product has been classified as Monitoring and Control
vi CR125A, CR175A, CR286A Clock Recovery Instruments Quick Start User Manual
TableofContents
Table of Contents
Introduction ........................................................................................................................................................ 1
Product Description ........................................................................................................................................... 1
Features and Benefits ....................................................................................................................................... 1
Key Specifications ........................................................................................................................................... 2
Documentation ................................................................................................................................................... 2
Optional Applications ...................................................................................................................................... 2
Other Documentation ....................................................................................................................................... 2
Installation .......................................................................................................................................................... 3
Standard Accessories ....................................................................................................................................... 3
Optional Accessories ........................................................................................................................................ 3
Operating Requirements .................................................................................................................................. 3
Preventing ESD ................................................................................................................................................ 4
Configuration ..................................................................................................................................................... 5
Front Panel ....................................................................................................................................................... 5
Operation ............................................................................................................................................................ 6
Power On ......................................................................................................................................................... 6
Setup ................................................................................................................................................................ 6
Use with Other Instruments ............................................................................................................................. 8
Maintenance ..................................................................................................................................................... 9
Specifications .................................................................................................................................................... 10
Index .................................................................................................................................................................. 11
CR125A, CR175A, CR286A Clock Recovery Instruments Quick Start User Manual vii
Introduction
Introduction
This Quick Start User Manual supports the Tektronix BERTScope CR125A, CR175A, and CR286A Clock
Recovery instruments.
The software-based graphical user interface is accessed through the Tektronix BERTScope Analyzer’s top level
‘Views’ Menu, listed as Clock Recovery Control. Detailed information on the operation of the control interface
can be accessed at any time through the Help menus available in any of the control views.
BERTScopePC Standalone Software installs the Clock Recovery instrument’s control interface on a usersupplied PC. The BERTScopePC software is included on the CD-ROM shipped with the Clock Recovery
instrument.
The instrument communicates with the Tektronix BERTScope Analyzer or Host PC through a USB interface. A
USB interconnect cable is provided with the product.
Product Description
The Tektronix BERTScope CR125A, CR175A, and CR286A are fully flexible clock recovery instruments
designed to make compliance testing of today’s communication designs easy and accurate. With jitter being
such a complex and contentious parameter, the Tektronix CR is intended to make compliance testing simple,
repeatable and accurate.
Many communication standards now specify that jitter testing must be carried out using a reference clock that
has been derived from the data signal using clock recovery with well defined loop bandwidth characteristics.
Typically these characteristics are specified in terms of the -3 dB bandwidth of the recovery loop, the rate of
roll-off of the frequency response, and the degree of response peaking allowable. These effects will greatly
dictate the amount of jitter that will be present on the reference clock, and therefore the amount of jitter
ultimately measured by test instrumentation.
The CR has been architected from the ground up to provide flexibility and accuracy in compliance
measurements. For easy verification of compliance, the correct characteristics are automatically set when a
given standard is selected from a pull-down menu. However, for users wanting to explore the limits of their
designs, full control of parameters is also easily available. A good example of this is for systems where
restricting the buildup of jitter is critical. Clock recovery plays a crucial role in this, and the ability to emulate a
clock recovery source with excessive peaking is a great way of understanding the system sensitivity to jitter
gain. The CR has variable jitter peaking that goes way beyond simple compliance, and allows jitter gain in
excess of 10 dB if desired.
The Tektronix BERTScope Clock Recovery instrument is the perfect companion to the Tektronix BERTScope
Bit Error Ratio Analyzer, sharing a common user interface. A single USB connection and supplied high quality
microwave coax cables connect the two units.
Features and Benefits
Features Benefits
Accurate, robust (including spread
spectrum clocking) clock recovery
Accurate, user-controllable PLL
bandwidth and peaking
Optional jitter spectrum analysis Spectral view and measurement of jitter in signal, calibration
Optional 24 MHz loop bandwidth For PCIe Gen 3 testing
Recover clock when no device or system clock is available,
jitter measurements cannot be any better than your clock
reference
Compliant clock recovery for standards testing, measured
DUT jitter is dependent on PLL bandwidth
stress for PCIe 5 GT/s receiver test
CR125A, CR175A, CR286A Clock Recovery Instruments Quick Start User Manual 1
Documentation
Key Specifications
Model
CR286A 1G to 28.6 Gb/s
CR175A 1G to 17.5 Gb/s
CR125A 1M to 12.5 Gb/s
Clock Recovery
Range
Documentation
In addition to this Quick Start Guide, the following documents are available:
Online Help
Programmer Online Guide
Optional Applications
Options available for BERTScope Clock Recovery Instruments:
PCIE Optional PLL Analysis
Max/min PLL
Loop BW (adj)
100 kHz-12 MHz,
200 kHz-12 MHz
above 14.3 GHZ
– up to 24 MHz
with option XLBW
ext loop BW
Input
Sensitivity
100 mV SE,
50 mV diff,
40 mV SE,
20 mV diff –
option HS
All typ.
Peaking (adj)
0-6 dB, 500
kHz-12 MHz,
0-5 dB
12 MHz – 24
MHz w/option
XLBW
Intrinsic
Jitter
250 fs
(typ)
XLBW Extended Bandwidth to 24 MHz
Other Documentation
Your instrument includes PDF files of relevant information:
Remote Control Programmer Guide PDF
Technical Specifications PDF
2 CR125A, CR175A, CR286A Clock Recovery Instruments Quick Start User Manual
Installation
Installation
The Tektronix Clock Recovery Instrument is intended to be operated in a controlled laboratory environment.
The CR is intended to operate on a bench top, or on top of another instrument such as the Tektronix
BERTScope Bit Error Ratio Analyzer. There are four shock-absorbing feet located on the bottom of the
instrument. Operate the instrument only when positioned with the feet facing downward. Do not operate the
instrument with the long axis vertical, standing on its side, as this will block the path of air required for cooling.
This instrument uses a low voltage ‘soft’ power switch that activates the power supply. The primary power
control circuitry is always live whenever the power cable is connected to the mains. The instrument is fuseprotected to reduce the risk of fire in the event of a power supply failure. Access to the power cable for
disconnection from the mains in an emergency may be required by local codes.
Standard Accessories
Power cord
USB cable
Documents
Rack mount hardware
Replacement fuse
BERTScopePC Standalone Software CD-ROM (installs the CR’s control interface on a user-supplied
PC)
Optional Accessories
CR125ACBL High performance Delay Matched Cable Set (required for BERTScope Analyzer
Operating Requirements
Place the instrument on a cart or bench. The instrument should rest on its bottom or rear feet. An optional rack
mounting kit is available. Observe the following clearance requirements and dimensions:
Top 0 mm (0 in)
Left and right sides 76 mm (3 in)
Bottom 0 mm (0 in) standing on feet, flip stands down
Rear 0 mm (0 in) on rear feet
Width 394 mm (15.5 in)
Height 220 mm (8.7 in)
Before operating the instrument, verify the ambient temperature:
+10° C to +40 °C (+41 °F to +113 °F)
and Clock Recovery instrument in SSC applications)
CR125A, CR175A, CR286A Clock Recovery Instruments Quick Start User Manual 3
Installation
Preventing ESD
A direct electrostatic discharge can damage the instrument input. To learn how to avoid this
damage, read the following information.
CAUTION
Electrostatic discharge (ESD) is a concern when handling any electronic equipment. The instrument is designed
with robust ESD protection; however it is still possible that large discharges of static electricity directly into the
signal input may damage the instrument. To avoid damage to the instrument, use the following techniques to
prevent electrostatic discharge to the instrument.
Discharge the static voltage from your body by wearing a grounded antistatic wrist strap while
connecting and disconnecting cables and adapters. The instrument provides a front panel connection
for this purpose.
A cable that is left unconnected on a bench can develop a large static charge. Discharge the static
voltage from all cables before connecting them to the instrument or device under test by momentarily
grounding the center conductor of the cable, or by connecting a 50 Ω termination to one end, prior to
attaching the cable to the instrument.
4 CR125A, CR175A, CR286A Clock Recovery Instruments Quick Start User Manual
Configuration
Configuration
Front Panel
Hardware connectors on the front panel of the Clock Recovery instrument:
Chassis Ground Data In + Data Out + Clock Out
Data In – Data Out – Subrate Clock Out
The power On/Off button is at the upper right and shows a green light when the unit is powered on. Below is
the adjustment knob, which can be used to scale inputs and to zoom.
CR125A, CR175A, CR286A Clock Recovery Instruments Quick Start User Manual 5
Operation
Operation
Power On
Connect the power supply cable to a properly grounded AC supply
Press the ‘ON’ button (green illumination should appear)
Ensure that proper precautions are observed against electrostatic discharge.
Using suitable high quality coaxial cables with APC-3.5, 2.92 mm, or SMA
connectors, connect to the front panel interface.
Setup
After the proper connections have been made for data input and clock output and the instrument has been
powered on, you can adjust the input settings.
NOTE
: Data outputs should be terminated if not in use or reflections will severely degrade performance.
Current settings are shown on the right side of the display. Use the knob or cursor keys to scroll through menu
items. Press the knob or enter key to select an item to adjust. Use the escape key to back out of a menu or cancel
an adjustment. When editing a numeric setting, use the left and right cursor keys to move through digits and use
the knob to make larger changes. Press the knob or enter key to accept a change, or press the escape key to
cancel changes.
Many industry standards are available from the front panel menu. Select a standard and the corresponding
nominal data rate, loop bandwidth, and peaking settings will be entered automatically.
The following settings can be entered manually:
Nominal Data Rate Nominal rate of the recovered clock
Lock Range The frequency range around the nominal rate that will be scanned during
locking
Bandwidth Bandwidth of the recovery loop measured at –3 dB
Peaking Peaking of the recovery loop. Also sets first or second order roll-off of
untracked jitter
Nominal Edge Density Expected edge density of incoming data. Required to set bandwidth
correctly.
Edge Density Mode Sets bandwidth. Calculations are based on Nominal Edge Density or edge
density measured during lock.
Clock Amplitude Output amplitude of the full rate clock.
Subrate Amplitude Output amplitude of the subrate clock.
Subrate Division Division ratio of the subrate clock.
6 CR125A, CR175A, CR286A Clock Recovery Instruments Quick Start User Manual
Operation
By default, all settings will be saved automatically on power off and restored at power on. You can also save
current settings to one of four Setups that can be recalled later.
Several continuously updated measurements are shown on the front panel display:
Frequency The measured frequency of the recovered clock.
Edge Density The measured edge density. A ‘1010’ data pattern transmitted at the Nominal
Data Rate would have 100% edge density.
Phase Error RMS The RMS phase error between the incoming data and the recovered clock.
Phase Error Pk-Pk The peak-to-peak phase error between the incoming data and the recovered
clock. This measured value will increase if jitter is present on the input data that
is not being tracked by the recovered clock.
Lock Status Reports whether the CR is locked, unlocked, or in the process of locking.
By default, the CR is configured in Auto Lock mode, where it will automatically attempt to acquire lock if the
detected Phase Error exceeds the Phase Error Limit setting, or the recovered clock is unstable. Pressing the
LOCK key on the CR front panel will force a relock.
The Clock Recovery instrument can be connected to a Tektronix BERTScope Analyzer through a USB cable,
allowing full control of the CR through the Analyzer’s touchscreen user interface. Press the Analyzer’s ‘View’
button to access the Clock Recovery Setup menu.
Device settings are selected using the buttons on the touchscreen. All functionality is available via the Analyzer
user interface, as well as through the Clock Recovery instrument’s front panel.
Graphing capability is available on the Tektronix BERTScope Analyzer by pressing the oval ‘To CR Analysis’
button at the top of the Analyzer’s Clock Recovery Control display (this Clock Recovery Analysis view can
also be selected from the initial ‘View’ menu).
CR125A, CR175A, CR286A Clock Recovery Instruments Quick Start User Manual 7
Operation
Use with Other Instruments
The Tektronix BERTScope CR can be used with other vendors’ BERTs, other instruments, or standalone. All of
the instrument’s functionality is accessible through a similar user interface provided by BERTScopePC
Standalone Software. The software operates in a Host PC. Operating system requirements are any 32-bit version
of Microsoft Windows
through USB, which is connected to the host computer rather than a BERTScope Analyzer. The software should
be installed in the host PC prior to connecting the USB cable.
BERTScopePC software is distributed on a CD-ROM, and is supplied as a standard accessory with the CR
instruments.
To connect to another instrument, here are some simple configurations to get you started:
Connecting the CR to a Tektronix BERTScope Analyzer
Analyzer Pattern Generator data output to Clock
Recovery data input
Clock Recovery data output to Analyzer Error
Detector data input
®
XP, Vista, or 2000. 64-bit versions are not supported. Control communication is
Clock Recovery clock output to Analyzer clock
input
Connecting the CR to a sampling oscilloscope
Data input to Clock Recovery from signal
under test
Clock Recovery data output to data input of
oscilloscope sampling module
Clock Recovery clock output to scope trigger
input
Connecting the CR to a BERT
BERT Pattern Generator data output to Clock
Recovery data input
Clock Recovery data output to BERT Error
Detector data input
Clock Recovery clock output to BERT clock
input
8 CR125A, CR175A, CR286A Clock Recovery Instruments Quick Start User Manual
Operation
Maintenance
Cleaning
The exterior of the instrument may be cleaned using a soft cloth dampened with a ‘glass and office desk
surface’ type cleaner. Do not use solvent or abrasive cleaning agents.
Connector Replacement
The DATA IN and DATA OUT connectors use 3.5 mm to APAC Planar Crown® adapters. These facilitate user
replacement of the adapter, should it become damaged. Replacement adapters can be ordered from Tektronix.
The adapter is secured to the connector with a captive threaded mounting ring. Remove a damaged connector by
grasping the knurled outer portion of the ring with your fingers and turning counter-clockwise. Do not allow
foreign material to enter the connector body when replacing the adapter. To install the replacement adapter,
position the two locating tabs in the corresponding slots of the instrument-mounted portion of the connector and
seat the adapter. With the adapter in place, align the retaining ring and tighten by rotating clockwise. The
connector should be tightened snugly ‘finger-tight.’ To avoid over-tightening and possibly damaging the
connector, do not use a tool to tighten it.
Fuse Replacement
The instrument is protected by a fuse placed in series with the power line input. The fuse is conservatively rated
and should never open through the life of the instrument. A blown fuse would generally indicate a problem with
the instrument which requires factory service. It is recommended that you arrange to have the instrument
serviced if you experience a blown fuse.
Calibration
The Clock Recovery instrument uses digital calibration of the output buffers. To maintain the accuracy of the
output amplitude and offset, annual calibration is recommended. Contact Tektronix to schedule instrument
calibration.
CR125A, CR175A, CR286A Clock Recovery Instruments Quick Start User Manual 9
Specifications
Specifications
Data:
Data Interfaces ........................................................................ 50 Ω differential or single-ended, DC-Coupled
APC 3.5 User-Replaceable Planar Crown
Data Rate Coverage ....................................................................................................... 150 Mb/s to 12.5 Gb/s
Data Insertion Loss .................................................................................................................. 0.8 dB (typical)
®
adapters
Clock:
Clock Interfaces ............................................................................................. 50 Ω single-ended, AC Coupled
APC 3.5 User-Replaceable Planar Crown
Clock Output Range ............................................................. 150 MHz to 12.5 GHz (Full Rate Clock Output)
Loop Bandwidth ................................................................................................... 2.5 kHz – 12 MHz variable.
Frequency Response Roll-Off ................................................................................................. -20 dB/ decade
Intrinsic Jitter .................................................................................................................................... < 1 ps rms
Input Sensitivity ................................................................................................ 100 mV single ended (typical)
50 mV differential (typical)
Clock Output Amplitude ...................................................................................................................... 300 mV
Divided Clock Output ......................................... Full rate divided by 2, 4, 5, 6, 7, 8, 9, 10, 12, 14, 16, 18, 20,
24, 28, 32, 36, 64, 80, 96, 112, 128, 144
Divided Clock Interface ............................................................................................................................ SMA
Divided Clock Jitter .......................................................................................................................... < 1 ps rms
®
adapters
General:
Displayed Information .................................. On the unit – PLL Loop Bandwidth, PLL Frequency Response,
Clock Phase against frequency & time
Communication......................................................... USB cable (supplied). Unit also provides hub capability
for 3 additional USB ports.
Physical:
Dimensions (W x H x D) .................................................................................................. 39.4 x 9.5 x 33.6 cm
(15.5 x 3.75 x 13.25 in)
Weight ....................................................................................................................................... 7.3 kg (16 lbs)
Power ........................................................................................................................................... 150 W Max.
Voltage....................................................................................................................... 100-240 VAC, 50/60 Hz
Power Fuse ...................................................................................... 3.15 A, 250 V, 5 mm x 20 mm, fast blow
Environmental:
Temperature, Operating .................................................................... +10 °C to +40 °C (+41 °F to +113 °F)
Temperature, Non-Operating .............................................................................................. −22 °C to +60 °C
Humidity ................................................................................................................. 20 – 80%, non-condensing
10 CR125A, CR175A, CR286A Clock Recovery Instruments Quick Start User Manual
Index
Index
A
Accessories
Optional .................................................................... 3
Standard ................................................................... 3
Applications .................................................................. 2
C
Compliance .................................................................. iv
EMC Compliance .................................................... iv
Environmental Considerations ................................ vi
Safety Compliance ................................................... v
Configuration
Front Panel ............................................................... 5
Connector
Replacement ............................................................. 9
Specification ........................................................... 10
Contact Tektronix
European Contact .................................................... iv
USA Contact ........................................................... iv
D
Documentation ............................................................. 2
E
Environmental Considerations
End-of-Life Handling .............................................. vi
Restriction of Hazardous Substances ...................... vi
WEEE, Recycling ................................................... vi
ESD Prevention ............................................................ 4
F
Features and Benefits .................................................... 1
Fuse
Replacement ............................................................. 9
Specification ........................................................... 10
I
Installation
Accessories ............................................................... 3
Operating Requirements ........................................... 3
Preventing ESD ........................................................ 4
M
Maintenance .................................................................. 9
O
Optional Applications ................................................... 2
P
Power
Power On .................................................................. 6
R
Remote Control PDF ..................................................... 2
S
Safety
General Safety Summary .......................................... ii
Preventing ESD ........................................................ 4
Safety Compliance .................................................... v
Symbols and Terms ................................................ iii
Setup
Connect to Other Instruments ................................... 8
Connect to Tektronix BERTScope Analzyer ............ 7
Manual Settings ........................................................ 6
Specifications .............................................................. 10
T
Technical Specifications PDF ....................................... 2
Technical Support ........................................................ iv
W
Warranty ........................................................................ i
WEEE .......................................................................... vi
CR125A, CR175A, CR286A Clock Recovery Instruments Quick Start User Manual 11
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