LeCroy MS-250 User manual

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LeCroy Corporation
700 Chestnut Ridge Road
Chestnut Ridge, NY 10977–6499
Tel: [phone], Fax: [phone]
Internet: www.lecroy.com
© 2009 by LeCroy Corporation. All rights reserved.
LeCroy, ActiveDSO, WaveLink, JitterTrack, WavePro, WaveMaster, WaveSurfer, WaveExpert,
and Waverunner are registered trademarks of LeCroy Corporation. Other product or brand names
are trademarks or requested trademarks of their respective holders. Information in this publication
supersedes all earlier versions. Specifications subject to change without notice.
Manufactured under an ISO 9000
Registered Quality Management System
Visit www.lecroy.com to view the
certificate.
This electronic product is subject to
disposal and recycling regulations
that vary by country and region.
Many countries prohibit the
disposal of waste electronic
equipment in standard waste
receptacles.
For more information about proper
disposal and recycling of your
LeCroy product, please visit
www.lecroy.com/recycle.
MS-250-OM-E Rev C
917366-00 Rev A

MS-250-OM-E Rev C ISSUED: June, 2009 3
TABLE OF CONTENTS
SAFETY REQUIREMENTS ..................................................................................5
Use and Maintenance......................................................................................................................5
INTRODUCTION...................................................................................................6
Overview ..........................................................................................................................................6
Warranty...........................................................................................................................................6
Returning a Product for Service or Repair.......................................................................................6
Technical Support.............................................................................................................................7
Staying Up-to-Date...........................................................................................................................7
STANDARD AND ACCESSORY EQUIPMENT ...................................................8
The MS-250 Standard Hardware .....................................................................................................8
The MS-250 Software ......................................................................................................................9
Accessories....................................................................................................................................10
DESCRIPTION OF OPERATION........................................................................12
GETTING STARTED WITH THE MS-250...........................................................13
Overview ........................................................................................................................................13
Connecting the MS-250 System to the Oscilloscope.....................................................................13
Verifying Proper MS-250 Connection to your Oscilloscope and the Device under Test................16
The Complete System Connection ................................................................................................16
Digital Connections ........................................................................................................................16
Channel Groupings.................................................................................................................17
Connector Colors....................................................................................................................17
Standard Output Connection ..................................................................................................17
Threshold Levels............................................................................................................................17
Minimum voltage swing..................................................................................................................19
Basic Oscilloscope Operation........................................................................................................19
ACCESSING THE MS-250 OSCILLOSCOPE MIXED SIGNAL OPTION
TOOLSET...........................................................................................................20
Overview ........................................................................................................................................20
Oscilloscope Analog Trigger and MS-250 Digital Trigger ..............................................................20
Digital Trace Groups.......................................................................................................................21
DIGITAL TRACE GROUP SETUP......................................................................23
Digital Trace Group Dialog.............................................................................................................23
Digital Logic Threshold Setup ........................................................................................................25
Overview.................................................................................................................................25
Digital Logic Setup..................................................................................................................26
DIGITAL TRIGGER SETUP................................................................................28
Overview ........................................................................................................................................28
Creating a Pattern Trigger..............................................................................................................28

MS-250 Mixed Signal Oscilloscope Option
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Logic Pattern Trigger Setup ...........................................................................................................29
Logic Bus Trigger Setup.................................................................................................................30
Digital Logic Threshold Setup ........................................................................................................30
CHARACTERIZE DIGITAL OR MIXED SIGNAL SYSTEM PERFORMANCE...32
Overview ........................................................................................................................................32
Using Cursors.................................................................................................................................32
Using Measurement Parameters ...................................................................................................33
Measurement Gating......................................................................................................................33
Using Statistics and Graphing........................................................................................................34
ISOLATE AND ANALYZE SIGNAL ACTIVITY..................................................35
Capture Long Pre-Trigger Time .....................................................................................................35
Zooming on Your Waveforms.........................................................................................................36
APPENDIX A –SPECIFICATIONS....................................................................38
CERTIFICATIONS..............................................................................................39
CE Declaration of Conformity.........................................................................................................39
EMC Directive ................................................................................................................................39
Electromagnetic Emissions:...........................................................................................................39
Electromagnetic Immunity: .....................................................................................................39
Low-Voltage Directive ....................................................................................................................39

MS-250-OM-E Rev C ISSUED: June, 2009 5
SAFETY REQUIREMENTS
This symbol may appear on the product:
This refers you to additional information contained in the operator’s manual. The corresponding
information in this manual is similarly denoted.
Before using this product, ensure that its operating environment will be maintained within these
parameters:
Temperature:
5 to 40 °C
Humidity:
Maximum relative humidity
80 % (non-condensing) for
temperatures up to 31 °C
decreasing linearly to 50 %
relative humidity at 40 °C
Altitude:
Up to 2,000 m
CAUTION
To avoid personal injury or damage to the MS-250 or any equipment connected to it, review and
comply with the following safety precautions.
Use only as intended. Use of the MS-250 and/or the equipment it is connected to in a
manner other than specified may impair the protection mechanisms.
Connect and disconnect properly. Avoid damage to cables thru excessive bending.
Do not use in wet/damp or explosive atmospheres.
For indoor use only. The MS-250 is intended for indoor use and should be operated
in a clean, dry, environment.
Do not operate with suspected failures. Do not use MS-250 if any part is damaged.
All maintenance should be referred to qualified service personnel.
Keep product surfaces clean and dry.
Use and Maintenance
The MS-250 is a high quality, precision instrument. To maintain accuracy and signal fidelity,
mechanical shock should be avoided, as well as damage to the cables through excessive
bending. All maintenance and component replacement should be referred to qualified personnel.
The outside of the MS-250 hardware should be cleaned with a soft cloth dampened with either
deionized / distilled water or isopropyl alcohol. Allow the surface to dry completely before
returning the instrument to service.

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INTRODUCTION
Overview
The MS-250 Oscilloscope Mixed Signal Option is a powerful solution for the challenge of
measuring multiple, mixed signals in a single oscilloscope. An enhancement tool to the LeCroy
WaveRunner Xi Series and WaveSurfer Xs Series oscilloscopes, the MS-250 extends their
testing range by adding 18 digital channels for display or triggering.
The MS-250 is ideally suited for embedded controller testing where there is a proliferation of
analog signals (comparators, voltage sources, sensor/actuator signals, etc.) coincident with digital
signals (address or data lines, control signals, or peripheral serial data signals). Users can easily
debug signals using standard oscilloscope tools such as cursors, measurement parameters, and
zooming.
Both oscilloscopes usable with the MS-250 feature large, bright color displays to facilitate signal
viewing, plus all the connectivity and documentation capabilities needed to quickly record and
distribute information.
This MS-250 manual assumes that you have a basic understanding of discrete electronics, logic
analyzers, and LeCroy oscilloscopes, specifically the LeCroy oscilloscope that the MS-250
system will be used with. When practical or necessary there are details on specific oscilloscope
features included in this manual.
Warranty
The MS-250 is warranted for normal use and operation, within specifications, for a period of one
year from shipment. LeCroy will either repair or, at our option, replace any product returned to
one of our authorized service centers within this period. However, in order to do this we must first
examine the product and find that the defect is due to workmanship or materials and not due to
misuse, neglect, accident, or abnormal conditions or operation.
LeCroy shall not be responsible for any defect, damage, or failure caused by any of the following:
a) attempted repairs or installations by personnel other than LeCroy representatives, or b)
improper connection to incompatible equipment, or c) for any damage or malfunction caused by
the use of non-LeCroy supplies.
Spare and replacement parts, and repairs, all have a 90-day warranty.
The oscilloscope’s firmware has been thoroughly tested and is presumed to be functional. This
includes MS-250 specific firmware. Nevertheless, it is supplied without warranty of any kind
covering detailed performance. Products not made by LeCroy are covered solely by the warranty
of the original equipment manufacturer.
Returning a Product for Service or Repair
If you suspect that you have a problem with the MS-250, you should first contact your local
LeCroy service center so that they can ascertain whether this component is defective.

MS-250-OM-E Rev C ISSUED: June, 2009 7
If you need to return a LeCroy product, provide model identification by providing the model name
and serial number, describe the defect or failure, and give us your name and telephone number.
For factory returns, use a Return Authorization Number (RAN), which you can get from customer
service. Write the number clearly on the outside of the shipping carton. Return products requiring
only maintenance to your local customer service center. Within the warranty period,
transportation charges to the service center are your responsibility.
Products under warranty are then returned to you with transport prepaid by LeCroy. Outside the
warranty period, you provide us with a purchase order number before the work can be done. You
are also billed for parts and labor related to the repair work and shipping.
It is highly recommended to prepay return shipments and use air freight. LeCroy cannot accept
COD (Cash On Delivery) or Collect Return shipments.
Technical Support
You can get assistance with installation and operation from your customer service center. Visit
the LeCroy Web site at http://www.lecroy.com for the center nearest you.
Staying Up-to-Date
Your MS-250 hardware does not need periodic calibration.
LeCroy offers state-of-the-art performance by continually refining and improving the instrument’s
capabilities and operation. We frequently update both firmware and software during service, free
of charge during warranty. Therefore, MS-250 specific software may be periodically updated. You
can download firmware and software updates from the LeCroy website.
Since software is continuously updated, the dialog boxes and menus you see in your program
may be slightly different than what is shown in this manual. These differences should not affect
your understanding of correctly operating the MS-250.

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STANDARD AND ACCESSORY EQUIPMENT
The MS-250 Standard Hardware
The Standard Hardware consists of the following items:
Qty. 1 Mixed Signal Oscilloscope Option –Provides 18
channel digital acquisition and triggering.
Qty. 1 16” (40.64 cm) Digital Lead Set –Interfaces the
MS-250 to the device under test. The lead set terminates
in a 25 mil pin socket. Micro-gripper probes of various
sizes are available as accessories from LeCroy, and may
be connected to the lead set.
The lead set is divided into two groups. Each lead within
the group is color-coded (to resistor color-coding standard)
and has an individual ground connection. In addition, there
are two common ground leads available for use.
Qty. 1 LeCroy Bus Cable –1.3m cable to connect Mixed
Signal Hardware to main oscilloscope unit, includes
USB2.0 cable. This connection provides timebase
synchronization, cross-triggering and power.
Qty. 5 3” Flexible Ground Lead – Lead for grounding
individual digital inputs (Qty. 10 for MS-500-36)

MS-250-OM-E Rev C ISSUED: June, 2009 9
Qty. 20 Ground Extender –Connect to ground port of any
digital input and make a simple signal and ground
connection to a 0.1” square pin header. (Qty. 40 with MS-
500-36)
Qty. 1 Carrying Case
Qty. 1 Quick Reference Guide
Qty. 1 Quick Reference Guide
Qty. 1 Operator’s Manual
The MS-250 Software
The standard MS-250 software adds the following capability to the LeCroy oscilloscope software
dialogs:
Analog, Digital and Combination Trigger Modes –Allows you to choose whether to set
an analog trigger condition, a digital trigger condition or a pattern consisting of analog
and digital signals.
Digital Trigger –Allows a digital trigger condition to be set from within the oscilloscope
using an easy-to-understand interface.
Digital Channels –Provides a standard, general purpose setup for defining the digital
channels and displaying digital lines.
Digital Threshold Setup –Provides the means to define a logic threshold for digital
trace calculation.
The MS-250 Hardware and Software requires no traceable calibration or adjustment. However,
the oscilloscope used with the MS-250 does require periodic calibration and adjustment.

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Accessories
The following accessories are also available for use with the MS-250.
MSO-DLS-18 16” (40.64 cm) Digital Lead Set –You may
find an additional standard digital lead set convenient if
you have more than one device under test and do not wish
to disconnect/reconnect your cables (when using the MS-
250 on different DUTs) Inputs are labeled D0 –D17.
PK400-1 –Large gripper probe set for 0.10 inch (2.54
mm) pin pitch. Includes 10 probes with color-coded leads.
PK400-2 –Medium gripper probe set for 0.04 inch (1.0
mm) pin pitch. Includes 10 probes with color-coded leads.

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PK400-3 –Small gripper probe set for 0.008 inch (0.2
mm) pin pitch. Includes 10 probes with color-coded leads.
MSO-MICTOR –Mictor Connection cable, 16” (40.64
cm), 36 channel connector.
MSO-3M - Interconnect cable, 16” (40.64 cm) mates with
3M connectors, 2520-6002 and 25205002.

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DESCRIPTIONOFOPERATION
The various components of the MS-250 Mixed Signal Option Oscilloscope acquire and store
digital data, trigger on digital patterns, interface the external module to the oscilloscope, and
provide a user-friendly interface for control and interpretation of data.
The MS-250 is an external device that digitally samples waveform data at up to 1 GS/s (for 250
MHz digital signals). Unlike a logic analyzer, it operates only in a Timing Analysis mode, so it
requires 4x oversampling to determine the correct digital edge position, and does not require the
user to input a clock.
While in SINGLE, NORMAL, or AUTO trigger mode, the MS-250 repeatedly samples each digital
channel’s voltage level. If the voltage is greater than the threshold voltage, the MS-250 stores a 1
in internal memory. Otherwise, a 0is stored.
1
Threshold level
1 1 1 1 1 0 0 0 0 1 1 1 1 1 0 0 0 0 0
The minimum high voltage level is user definable by the hysteresis control up to 1.4 V above the
threshold. The maximum low voltage level is user definable by the hysteresis control up to 1.4 V
below the threshold. The minimum signal swing is 100 mV. The indeterminate range of 50 mV
around the threshold voltage level is the level below which the MS-500 will not operate. However,
the MS-500 can support a signal as low as 100mV only if the input signal’s quality is adequate.
The MS-250 keeps sampling its inputs until the oscilloscope is put into STOP trigger mode. Data
is stored in a 50 Mpt internal memory that is periodically transferred to the oscilloscope via the
USB2.0 cable. If the oscilloscope is triggering in SINGLE or NORMAL trigger mode, data is
acquired and transferred only when the trigger condition is satisfied. The captured data is then
displayed on the oscilloscope grid in a time-aligned fashion.
In any trigger mode (AUTO, NORMAL, SINGLE), pressing STOP trigger cancels the acquisition,
which leaves the previously acquired data unchanged.
The MS-250 both samples incoming data and searches for trigger conditions.
The USB2.0 cable provides downloading of trigger conditions from the oscilloscope to the MS-
250 and uploading of digital data from the MS-250 to the oscilloscope.

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GETTING STARTED WITH THE MS-250
Overview
The MS-250 is a complete system that interfaces with the oscilloscope in a number of ways that
make it easier to do the following:
Set analog, digital and combination triggers.
View all analog and digital signal information on the oscilloscope grid, with all signals
time-correlated.
All setup is done in the user-friendly oscilloscope dialogs –it is not required to leave the
oscilloscope software to run the MS-250. All normal oscilloscope tools (cursors, measurement
parameters, etc.) are available for use with the digital signals.
There are physical connections that must be made to ensure proper operation, but the intuitive
connection steps are documented here.
Operation of the WaveRunner or WaveSurfer oscilloscope is not covered in this manual.
Reference the On-Line Help or Getting Started Manual for each oscilloscope for complete
information on analog triggering, display of analog signals, front panel operation, etc.
Connecting the MS-250 System to the Oscilloscope
Connect the MS-250 System to the Oscilloscope as follows:
1. Connect the LeCroy Bus Cable to the
LeCroy Bus connector on the side of
the oscilloscope and fasten the thumb
screws.

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2. Connect the USB 2.0 cable (attached
to the LeCroy Bus cable) to any of the
side mounted USB ports on the
oscilloscope.
3. Connect the other end of the LeCroy
Bus cable to the MS-250 and fasten
the thumb screws.

MS-250-OM-E Rev C ISSUED: June, 2009 15
4. Connect the other end of the USB2.0
Cable to the MS-250.
5. Connect the Digital Lead Set to the
other end of the MS-250 (labeled
Digital Inputs, D0 –D17) and fasten
the thumb screws.
6. Note that each digital line has a
ground connection for optimal
performance. Two additional ground
leads are also available. Using the
shortest possible ground lead is
always recommended.
Connect the Digital Leads to the digital
lines you wish to observe (using
accessory micro-grippers, as
necessary or desired).
7. Turn on power to the oscilloscope and
wait for the oscilloscope application to
begin.

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16 ISSUED: June, 2009 MS-250-OM-E Rev C
Verifying Proper MS-250 Connection to your Oscilloscope and the Device under Test
If you are concerned that your digital signals aren’t being displayed correctly, it is a good idea to
check by viewing the digital signals one at a time with an analog channel. This can point out
errors in your connection or in your logic threshold setup.
The Complete System Connection
When your system is connected properly it looks like the following photo:
It is usually easiest to debug digital line connection or display problems by viewing the digital
information on an analog channel to confirm its presence, then working back through the previous
sequence to determine where the connection or display error is.
Digital Connections
Handle with care!
The MS-250 Digital Lead Set connectors are fragile. Pull the
connector base, not the wire. Never bend the connectors.

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Channel Groupings
Each 18 channel lead set is divided into two physical groups of 9 and each group is bundled with
a plastic separator.
Note: The grouping you assign to the digital lines in the software interface can be different than the physical grouping of
digital lines. The physical grouping is intended for easy identification of all 18 digital lines.
Connector Colors
The wires in each color group use 9 repeating colors
The color sequence corresponds to the resistor color code making it easier to know the digital line
number without having to look at the label.
Standard Output Connection
The standard terminations on the digital lead sets can be pushed directly onto 25-mil pins.
MicroGrippers or NanoGrippersmay also be used to probe the test circuit’s pins. LeCroy provides
a selection of small, medium, and large grippers for various pitch sizes. A more complete
selection of adapter probes is available for most chips from Emulation Technology Inc., Yamaichi
Inc., and other manufacturers.
Threshold Levels
The threshold level determines how the input signal is interpreted. The threshold level can be set
in either the Digital Grouping Setup or Pattern Trigger Setup dialogs (it is the same setup, but is in
two different places for operator convenience).

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Input voltages less than the threshold are converted to 0. Input voltages greater than the
threshold are converted to 1.
Digitized
waveform
Input
signal
Threshold level
Sample points
The threshold levels can be set between –10.0 V and +10.0 V. TTL circuits use a threshold
voltage level of 1.58 V. ECL circuits use a threshold voltage level of -1.39 V. Other threshold
settings are available in the setup dialog.

MS-250-OM-E Rev C ISSUED: June, 2009 19
Minimum voltage swing
The minimum high voltage level is user definable by the hysteresis control up to 1.4 V above the
threshold. The maximum low voltage level is user definable by the hysteresis control up to 1.4 V
below the threshold. The minimum signal swing is 100 mV. The indeterminate range of 50 mV
around the threshold voltage level is the level below which the MS-250 will not operate. However,
the MS-250 can support a signal as low as 100 mV only if the input signal’s quality is adequate.
Basic Oscilloscope Operation
For information on using the oscilloscope to view analog signals, reference your oscilloscope On-
Line Help system.
Threshold from + 50 mV to + 1.4 V
Threshold from - 50 mV to - 1.4 V

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20 ISSUED: June, 2009 MS-250-OM-E Rev C
ACCESSING THE MS-250 OSCILLOSCOPE MIXED SIGNAL OPTION TOOLSET
Overview
MS-250 trigger and digital line display tools are easily accessible in a variety of ways. The MS-
250 option adds additional dialogs (menus) to the existing oscilloscope. These dialogs are
defined as:
Digital setup –allows set up of the Digital lines and definition/display of parallel buses.
These dialogs are roughly analogous to the analog Channel setup dialogs in terms of
how they are accessed and how they operate in the software. However, there are no
dedicated front panel controls for digital channels as there are with analog channels.
Logic Setup –allows setup of the logic threshold value that defines the digital trace.
When the MS-250 is connected to the oscilloscope, these dialogs are conveniently accessed
with just one or two touches of the screen, making adjustment fast and easy.
Oscilloscope Analog Trigger and MS-250 Digital Trigger
A standard WaveRunner or WaveSurfer oscilloscope only allows analog triggering. The addition
of the MS-250 option adds enhanced triggering; the digital channels are now available in the
oscilloscope trigger menu as trigger sources.
To operate the oscilloscope with a normal analog trigger, simply open the trigger dialog, and then
select one of the oscilloscope channels as the source. For more information on setting up an
Analog trigger, consult your oscilloscope On-Line Help or Getting Started Manual.
When the MS-250 is connected to the oscilloscope, the trigger type defaults to Pattern Trigger,
and the Pattern Trigger tab is automatically displayed on the oscilloscope display dialog. If
desired, touch the Close button to not display the dialog.