Keithley Keithley Instruments 7035 Manual

I

l

Test Equipment Depot - 800.517.8431 - 99 Washington Street Melrose, MA 02176 - TestEquipmentDepot.com

nstruction Manua

Model 7035

9-Bank, 1×4 Multiplexer Card

Contains Operating and Servicing Information

7035-901-01 Rev. A / 5-97

WARRANTY

Keithley Instruments, Inc. warrants this product to be free from defects in material and workmanship for a period of 1 year from date of
shipment.

Keithley Instruments, Inc. warrants the following items for 90 days from the date of shipment: probes, cables, rechargeable batteries,
diskettes, and documentation.

During the warranty period, we will, at our option, either repair or replace any product that proves to be defective.

To exercise this warranty, write or call your local Keithley representative, or contact Keithley headquarters in Cleveland, Ohio. You will
be given prompt assistance and return instructions. Send the product, transportation prepaid, to the indicated service facility. Repairs
will be made and the product returned, transportation prepaid. Repaired or replaced products are warranted for the balance of the origi­nal warranty period, or at least 90 days.

LIMITATION OF W

ARRANTY

This warranty does not apply to defects resulting from product modification without Keithley’s express written consent, or misuse of
any product or part. This warranty also does not apply to fuses, software, non-rechargeable batteries, damage from battery leakage, or
problems arising from normal wear or failure to follow instructions.

THIS WARRANTY IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESSED OR IMPLIED, INCLUDING ANY IMPLIED
WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE. THE REMEDIES PROVIDED HEREIN ARE
BUYER’S SOLE AND EXCLUSIVE REMEDIES.

NEITHER KEITHLEY INSTRUMENTS, INC. NOR ANY OF ITS EMPLOYEES SHALL BE LIABLE FOR ANY DIRECT, INDI­RECT, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OF ITS INSTRUMENTS AND
SOFTWARE EVEN IF KEITHLEY INSTRUMENTS, INC., HAS BEEN ADVISED IN ADVANCE OF THE POSSIBILITY OF
SUCH DAMAGES. SUCH EXCLUDED DAMAGES SHALL INCLUDE, BUT ARE NOT LIMITED TO: COSTS OF REMOVAL
AND INSTALLATION, LOSSES SUSTAINED AS THE RESULT OF INJURY TO ANY PERSON, OR DAMAGE TO PROPERTY.

CHINA: Keithley Instruments China • Yuan Chen Xin Building, Room 705 • 12 Yumin Road, Dewai, Madian • Beijing 100029 • 8610-62022886 • Fax: [phone]
FRANCE: Keithley Instruments SARL • BP 60 • 3 Allée des Garays • 91122 Palaiseau Cédex • 33-1-60-11-51-55 • Fax: [phone]
GERMANY: Keithley Instruments GmbH • Landsberger Strasse 65 • D-82110 Germering, Munich • 49-89-8493070 • Fax: [phone]
GREAT BRITAIN: Keithley Instruments, Ltd. • The Minster • 58 Portman Road • Reading, Berkshire RG30 1EA • 44-118-9575666 • Fax: [phone]
ITALY: Keithley Instruments SRL • Viale S. Gimignano 38 • 20146 Milano • 39-2-48303008 • Fax: [phone]
NETHERLANDS: Keithley Instruments BV • Avelingen West 49 • 4202 MS Gorinchem • 31-(0)183-635333 • Fax: [phone]
SWITZERLAND: Keithley Instruments SA • Kriesbachstrasse 4 • 8600 Dübendorf • 41-1-8219444 • Fax: [phone]
TAIWAN: Keithley Instruments Taiwan • 1FL., 1, Min Yu First Street • Hsinchu, Taiwan, R.O.C. • 886-35-778462 • Fax: [phone]

Model 7035 9-Bank, 1

Instruction Manual

×

4 Multiplexer Card

©1997, Keithley Instruments, Inc.

All rights reserved.
Cleveland, Ohio, U.S.A.
First Printing, May 1997

Document Number: 7035-901-01 Rev. A

Manual Print History

The print history shown below lists the printing dates of all Revisions and Addenda created for this manual. The Revision
Level letter increases alphabetically as the manual undergoes subsequent updates. Addenda, which are released between Revi­sions, contain important change information that the user should incorporate immediately into the manual. Addenda are num­bered sequentially. When a new Revision is created, all Addenda associated with the previous Revision of the manual are
incorporated into the new Revision of the manual. Each new Revision includes a revised copy of this print history page.

Many product updates and revisions do not require manual changes and, conversely, manual corrections may be done without
accompanying product changes. Therefore, it is recommended that you review the Manual Update History.

Revision A (Document Number 7035-901-01)......................................................................................... May 1997

All Keithley product names are trademarks or registered trademarks of Keithley Instruments, Inc.
Other brand and product names are trademarks or registered trademarks of their respective holders.

Safety Precautions

The following safety precautions should be observed before using
this product and any associated instrumentation. Although some in­struments and accessories would normally be used with non-haz­ardous voltages, there are situations where hazardous conditions
may be present.

This product is intended for use by qualified personnel who recog­nize shock hazards and are familiar with the safety precautions re­quired to avoid possible injury. Read the operating information
carefully before using the product.

The types of product users are:

Responsible body is the individual or group responsible for the use

and maintenance of equipment, and for ensuring that operators are
adequately trained.

Operators use the product for its intended function. They must be

trained in electrical safety procedures and proper use of the instru­ment. They must be protected from electric shock and contact with
hazardous live circuits.

Maintenance personnel perform routine procedures on the product

to keep it operating, for example, setting the line voltage or replac­ing consumable materials. Maintenance procedures are described in
the manual. The procedures explicitly state if the operator may per­form them. Otherwise, they should be performed only by service
personnel.

Service personnel are trained to work on live circuits, and perform

safe installations and repairs of products. Only properly trained ser­vice personnel may perform installation and service procedures.

Exercise extreme caution when a shock hazard is present. Lethal
voltage may be present on cable connector jacks or test fixtures.The
American National Standards Institute (ANSI) states that a shock
hazard exists when voltage levels greater than 30V RMS, 42.4V
peak, or 60VDC are present.

pect that hazardous voltage is present in any un­known circuit before measuring.

A good safety practice is to ex-

Users of this product must be protected from electric shock at all
times. The responsible body must ensure that users are prevented
access and/or insulated from every connection point. In some cases,
connections must be exposed to potential human contact. Product
users in these circumstances must be trained to protect themselves
from the risk of electric shock. If the circuit is capable of operating
at or above 1000 volts,

exposed.

As described in the International Electrotechnical Commission
(IEC) Standard IEC 664, digital multimeter measuring circuits
(e.g., Keithley Models 175A, 199, 2000, 2001, 2002, and 2010)
measuring circuits are Installation Category II. All other instru­ments’ signal terminals are Installation Category I and must not be
connected to mains.

Do not connect switching cards directly to unlimited power circuits.
They are intended to be used with impedance limited sources.
NEVER connect switching cards directly to AC mains. When con­necting sources to switching cards, install protective devices to lim­it fault current and voltage to the card.

Before operating an instrument, make sure the line cord is connect­ed to a properly grounded power receptacle. Inspect the connecting
cables, test leads, and jumpers for possible wear, cracks, or breaks
before each use.

For maximum safety, do not touch the product, test cables, or any
other instruments while power is applied to the circuit under test.
ALWAYS remove power from the entire test system and discharge
any capacitors before: connecting or disconnecting cables or jump­ers, installing or removing switching cards, or making internal
changes, such as installing or removing jumpers.

Do not touch any object that could provide a current path to the
common side of the circuit under test or power line (earth) ground.
Always make measurements with dry hands while standing on a
dry, insulated surface capable of withstanding the voltage being
measured.

no conductive part of the circuit may be

Do not exceed the maximum signal levels of the instruments and ac­cessories, as defined in the specifications and operating informa­tion, and as shown on the instrument or test fixture panels, or
switching card.

When fuses are used in a product, replace with same type and rating
for continued protection against fire hazard

Chassis connections must only be used as shield connections for
measuring circuits, NOT as safety earth ground connections.

If you are using a test fixture, keep the lid closed while power is ap­plied to the device under test. Safe operation requires the use of a
lid interlock.

If a screw is present, connect it to safety earth ground using the
wire recommended in the user documentation.

!

The symbol on an instrument indicates that the user should re­fer to the operating instructions located in the manual.

The symbol on an instrument shows that it can source or mea­sure 1000 volts or more, including the combined effect of normal
and common mode voltages. Use standard safety precautions to
avoid personal contact with these voltages.

The

WARNING heading in a manual explains dangers that might

result in personal injury or death. Always read the associated infor­mation very carefully before performing the indicated procedure.

Instrumentation and accessories shall not be connected to humans.

Before performing any maintenance, disconnect the line cord and
all test cables.

To maintain protection from electric shock and fire, replacement
components in mains circuits, including the power transformer, test
leads, and input jacks, must be purchased from Keithley Instru­ments. Standard fuses, with applicable national safety approvals,
may be used if the rating and type are the same. Other components
that are not safety related may be purchased from other suppliers as
long as they are equivalent to the original component. (Note that se­lected parts should be purchased only through Keithley Instruments
to maintain accuracy and functionality of the product.) If you are
unsure about the applicability of a replacement component, call a
Keithley Instruments office for information

To clean the instrument, use a damp cloth or mild, water based
cleaner. Clean the exterior of the instrument only. Do not apply
cleaner directly to the instrument or allow liquids to enter or spill
on the instrument.

The

CAUTION heading in a manual explains hazards that could

damage the instrument. Such damage may invalidate the warranty.

M

ODEL

7035 S

PECIFICATIONS

MULTIPLEX CONFIGURATION: Nine independent 1×4 2-pole

multiplex banks.

CONTACT CONFIGURATION: 2-pole Form A (Hi, Lo).
CONNECTOR TYPE: 96-pin male DIN connector.
MAXIMUM SIGNAL LEVEL: 60VDC, 30V rms, 42V peak betwen any

two inputs or chassis, 1A switched. 30VA (resistive load).

CONTACT LIFE: Cold Switching: 10

8

closures.

At Maximum Signal Levels: 10

5

closures.

CHANNEL RESISTANCE (per conductor): <1Ω.
CONTACT POTENTIAL: <1µV per channel contact pair

<3µV typical per single contact.

OFFSET CURRENT: <100pA.
ACTUATION TIME: 3ms.
ISOLATION: Bank: >10

9

Ω, <25 pF.

Channel to Channel: >10

9

Ω, <50 pF.

Differential: >10

9

Ω, <100pF.

Common Mode: >10

9

Ω, <200pF.

CROSSTALK (1MHz,50Ω Load): Bank: <–40dB.

Channel: <–40dB.

INSERTION LOSS (50Ω Source, 50 Load): <0.25dB below 1MHz,

<3dB below 10MHz.

RELAY DRIVE CURRENT (per relay): 16mA.
ENVIRONMENT: Operating: 0° to 50°C, up to 35°C <80% RH.

Storage: –25°C to 65°C.

EMC: Conforms with European Union Directive 89/336/EEC

EN 55011, EN 50082-1, EN 61000-3-2 and 61000-3-3, FCC part 15
class B.

SAFETY: Conforms with European Union Directive 73/23/EEC

EN 61010-1, UL 3111-1.

Channel 1

HI

LO

Bank A

Channels 2–3

HI

LO

Channel 4

HI

Output

LO

Channel 1

HI

LO

Bank I

Channels 2–3

HI

LO

Channel 4

HI

Output

LO

Specifications are subject to change without notice.

Table of Contents

1 General Information

Introduction......................................................................................................................................................... 1-1

Features ............................................................................................................................................................... 1-1

Warranty information.......................................................................................................................................... 1-1

Manual addenda .................................................................................................................................................. 1-2

Safety symbols and terms ................................................................................................................................... 1-2

Specifications ...................................................................................................................................................... 1-2

Unpacking and inspection................................................................................................................................... 1-2

Inspection for damage................................................................................................................................. 1-2

Handling precautions ................................................................................................................................. 1-2

Shipping contents........................................................................................................................................ 1-2

Instruction manual....................................................................................................................................... 1-2

Repacking for shipment ...................................................................................................................................... 1-3

Optional accessories............................................................................................................................................ 1-3

2 Multiplexer Configuration

Introduction......................................................................................................................................................... 2-1

Basic multiplexer configuration.......................................................................................................................... 2-1

Typical multiplexer switching schemes.............................................................................................................. 2-2

Single-ended switching ............................................................................................................................... 2-2

Differential switching ................................................................................................................................. 2-2

Sensing ........................................................................................................................................................ 2-3

SMU connections........................................................................................................................................ 2-3

Multiplexer expansion......................................................................................................................................... 2-4

i

3 Card Connections and Installation

Introduction ......................................................................................................................................................... 3-1

Handling precautions........................................................................................................................................... 3-1

Multi-pin (mass termination) connections........................................................................................................... 3-1

Typical connection technique...................................................................................................................... 3-4

Typical connection scheme ......................................................................................................................... 3-6

Model 7035 installation and removal .................................................................................................................. 3-8

Card installation........................................................................................................................................... 3-8

Card removal ............................................................................................................................................... 3-8

4 Operation

Introduction ......................................................................................................................................................... 4-1

Power limits......................................................................................................................................................... 4-1

Maximum signal levels................................................................................................................................ 4-1

Mainframe control of card................................................................................................................................... 4-1

Channel assignments ................................................................................................................................... 4-2

Closing and opening channels ..................................................................................................................... 4-4

Scanning channels ....................................................................................................................................... 4-4

IEEE-488 bus operation .............................................................................................................................. 4-5

Multiplexer switching examples.......................................................................................................................... 4-6

Two-wire resistance tests ............................................................................................................................ 4-6

Four-wire resistance tests ............................................................................................................................ 4-7

Measurement considerations ............................................................................................................................... 4-7

Path isolation ............................................................................................................................................... 4-7

Magnetic fields ............................................................................................................................................ 4-8

Radio frequency interference ...................................................................................................................... 4-8

Ground loops ............................................................................................................................................... 4-9

Keeping connectors clean............................................................................................................................ 4-9

AC frequency response................................................................................................................................ 4-9

5 Service Information

Introduction ......................................................................................................................................................... 5-1

Handling and cleaning precautions ..................................................................................................................... 5-1

Performance verification ..................................................................................................................................... 5-2

Environmental conditions............................................................................................................................ 5-2

Recommended equipment ........................................................................................................................... 5-2

Multiplexer connections .............................................................................................................................. 5-2

Channel resistance tests............................................................................................................................... 5-3

Offset current tests....................................................................................................................................... 5-4

Contact potential tests.................................................................................................................................. 5-6

Bank and channel-to-channel isolation tests ............................................................................................... 5-8

Differential and common-mode isolation tests.......................................................................................... 5-12

Special handling of static-sensitive devices ...................................................................................................... 5-16

Principles of operation....................................................................................................................................... 5-16

Block diagram ........................................................................................................................................... 5-16

ID data circuits .......................................................................................................................................... 5-17

Relay control ............................................................................................................................................. 5-17

Relay power control .................................................................................................................................. 5-17

ii

Power-on safeguard................................................................................................................................... 5-18

Troubleshooting ................................................................................................................................................ 5-18

Troubleshooting equipment ...................................................................................................................... 5-18

Troubleshooting access ............................................................................................................................. 5-18

Troubleshooting procedure ....................................................................................................................... 5-18

6 Replaceable Parts

Introduction......................................................................................................................................................... 6-1

Parts lists ..............................................................................................................................................................6-1

Ordering information .......................................................................................................................................... 6-1

Factory service .................................................................................................................................................... 6-1

Component layouts and schematic diagrams ...................................................................................................... 6-1

Index

iii

List of Illustrations

2 Multiplexer Configuration

Figure 2-1 Model 7035 simplified schematic ............................................................................................................... 2-1

Figure 2-2 Single-ended switching example................................................................................................................. 2-2

Figure 2-3 Differential switching example ................................................................................................................... 2-2

Figure 2-4 Sensing example ......................................................................................................................................... 2-3

Figure 2-5 SMU connections ........................................................................................................................................ 2-3

Figure 2-6 Multiplexer expansion example .................................................................................................................. 2-4

3 Card Connections and Installation

Figure 3-1 Multi-pin connector card terminal identification ........................................................................................ 3-2

Figure 3-2 Typical round cable connection techniques ................................................................................................ 3-4

Figure 3-3 Model 7011-MTR connector pinout ........................................................................................................... 3-5

Figure 3-4 Model 7011-KIT-R (cable) assembly ......................................................................................................... 3-5

Figure 3-5 Typical connection scheme for Model 7035 ............................................................................................... 3-7

Figure 3-6 Model 7035 card installation in Model 7001 .............................................................................................. 3-8

4 Operation

Figure 4-1 Model 7001 channel status display ............................................................................................................. 4-2

Figure 4-2 Model 7002 channel status display (slot 1)................................................................................................. 4-2

Figure 4-3 Display organization for multiplexer channels ........................................................................................... 4-3

Figure 4-4 Channel assignments ................................................................................................................................... 4-3

Figure 4-5 Two-wire resistance testing......................................................................................................................... 4-6

Figure 4-6 1x36 multiplex bank.................................................................................................................................... 4-6

Figure 4-7 Four-wire resistance testing ........................................................................................................................ 4-7

Figure 4-8 Path isolation resistance .............................................................................................................................. 4-8

Figure 4-9 Voltage attenuation by path isolation resistance ......................................................................................... 4-8

Figure 4-10 Power line ground loops ............................................................................................................................. 4-9

Figure 4-11 Eliminating ground loops............................................................................................................................ 4-9

v

5 Service Information

Figure 5-1 Path resistance test connections................................................................................................................... 5-3

Figure 5-2 Differential offset current test connections ................................................................................................. 5-5

Figure 5-3 Contact potential test connections ............................................................................................................... 5-7

Figure 5-4 Bank isolation test connections ................................................................................................................... 5-8

Figure 5-5 Channel-to-channel isolation test connections .......................................................................................... 5-10

Figure 5-6 Differential isolation test connections ....................................................................................................... 5-13

Figure 5-7 Common-mode isolation test connections................................................................................................. 5-15

Figure 5-8 Model 7035 block diagram........................................................................................................................ 5-16

Figure 5-9 Start and stop sequences ............................................................................................................................ 5-17

Figure 5-10 Transmit and acknowledge sequence ........................................................................................................ 5-17

vi

List of Tables

3 Card Connections and Installation

Table 3-1 Multi-pin connector card terminal designation cross-reference.................................................................. 3-3

Table 3-2 Mass termination accessories...................................................................................................................... 3-3

4 Operation

Table 4-1 Paired channels in four-wire resistance example ........................................................................................ 4-7

5 Service Information

Table 5-1 Verification equipment ............................................................................................................................... 5-2

Table 5-2 Bank isolation test summary ....................................................................................................................... 5-9

Table 5-3 Channel-to-channel isolation test summary.............................................................................................. 5-11

Table 5-4 Differential and common-mode isolation testing...................................................................................... 5-14

Table 5-5 Recommended troubleshooting equipment............................................................................................... 5-18

Table 5-6 Troubleshooting procedure ....................................................................................................................... 5-19

6 Replaceable Parts

Table 6-1 Relay board for Model 7035 parts list ........................................................................................................ 6-2

Table 6-2 Mass-terminated connector board for Model 7035 parts list ...................................................................... 6-3

Table 6-3 Model 7011-KIT-R 96-pin female DIN connector kit parts list .................................................................. 6-3

vii

1

General Information

Introduction

This section contains general information about the Model
7035 9-Bank, 1 × 4 Multiplexer Card.

The Model 7035 assembly consists of a multi-pin (mass ter­mination) connector card and a relay card. External test cir­cuit connections to the Model 7035 are made via the 96-pin
male DIN connector on the connector card. Keithley offers a
variety of optional accessories that can be used to make con­nections to the connector card. See the available optional
accessories at the end of this section.

The rest of Section 1 is arranged in the following manner:

• Features

• Warranty information

• Manual addenda

• Safety symbols and terms

• Specifications

• Unpacking and inspection

• Repacking for shipment

• Optional accessories

Features

The Model 7035 is a general purpose multiplexer card with
nine independent, 1 × 4, two-pole, multiplex banks. Some of
the key features include:

• Low contact potential and offset current for minimal
effects on low-level signals.

• High isolation resistance (>1G Ω ) for minimal load
effects.

• Model 7011-KIT-R connector kit that includes a 96-pin
female DIN connector that will mate directly to the con­nector on the Model 7035 or to a standard 96-pin male
DIN bulkhead connector (see Model 7011-MTR). This
connector uses solder cups for connections to external
circuitry and includes an adapter for a round cable and
the housing.

Warranty information

Warranty information is located at the front of this instruc­tion manual. Should your Model 7035 require warranty ser­vice, contact the Keithley representative or authorized repair
facility in your area for further information. When returning
the card for repair, be sure to fill out and include the service
form at the back of this manual in order to provide the repair
facility with the necessary information.

1-1

General Information

Manual addenda

Any improvements or changes concerning the card or man­ual will be explained in an addendum included with the card.
Addenda are provided in a page-replacement format.
Replace the obsolete pages with the new pages.

Safety symbols and terms

The following symbols and terms may be found on an instru­ment or used in this manual.

The symbol on an instrument indicates that you
should refer to the operating instructions located in the
instruction manual.

The symbol on an instrument shows that high voltage
may be present on the terminal(s). Use standard safety pre­cautions to avoid personal contact with these voltages.

The WARNING heading used in this manual explains dan­gers that might result in personal injury or death. Always
read the associated information very carefully before per­forming the indicated procedure.

The CAUTION heading used in this manual explains haz­ards that could damage the card. Such damage may invali­date the warranty.

!

contamination that could degrade its performance. Before
removing the card from the bag, observe the following pre­cautions on handling.

Handling precautions

1. Always grasp the card by the side edges and shields. Do
not touch the board surfaces or components.

2. When not installed in a Model 7001/7002 mainframe,
keep the card in the anti-static bag and store it in the
original packing carton.

After removing the card from its anti-static bag, inspect it for
any obvious signs of physical damage. Report any such dam­age to the shipping agent immediately.

Shipping contents

The following items are included with every Model 7035
order:

• Model 7035 9-Bank, 1 × 4 Multiplexer Card

• Model 7011-KIT-R 96-pin Female DIN Connector Kit

• Model 7035 Instruction Manual

• Additional accessories as ordered

Instruction manual

Specifications

Model 7035 specifications may be found at the front of this
manual. These specifications are exclusive of the Model
7001/7002 mainframe specifications

Unpacking and inspection

Inspection for damage

The Model 7035 is packaged in a resealable, anti-static bag
to protect it from damage due to static discharge and from

The Model 7035 Instruction Manual is three-hole drilled so
it can be added to the three-ring binder of the Model 7001 or
Model 7002 Instruction Manual. After removing the plastic
wrapping, place the manual in the binder following the main­frame instruction manual. Note that a manual identificatio
tab is included and should precede the multiplexer card
instruction manual.

If an additional instruction manual is required, order the
manual package, Keithley part number 7035-901-00. The
manual package includes an instruction manual and any per­tinent addenda.

1-2

General Information

Repacking for shipment

Should it become necessary to return the Model 7035 for
repair, carefully pack the unit in its original packing carton,
or the equivalent, and include the following information:

• Advise as to the warranty status of the card.

• Write ATTENTION REPAIR DEPARTMENT on the
shipping label.

• Fill out and include the service form located at the back
of this manual.

Optional accessories

The following accessories are available for use with the
Model 7035:

Model 7011-MTC-2 — This two-meter round cable assem-

bly is terminated with a 96-pin female DIN connector on
each end. It will mate directly to the connector on the
Model 7035 and to a standard 96-pin male DIN bulkhead
connector (see Model 7011-MTR).

Model 7011-MTR  This 96-pin male DIN bulkhead con-

nector uses solder cups for connections to external circuitry.
It will mate to the Model 7011-KIT-R connector and Model
7011-MTC-2 cable assembly.

1-3

2

Multiplexer Configuration

Introduction

This section covers the basics for multiplexer switching and
is arranged as follows:

• Basic multiplexer configuration — Covers the basic
multiplexer configuration

• Typical multiplexer switching schemes — Explains
some of the basic ways a multiplexer can be used to
source or measure. Covers single-ended switching, dif­ferential (floating) switching, sensing, and SMU
connections.

• Multiplexer expansion — Discusses how to configur
a larger multiplexer configuration

Basic multiplexer configuration

A simplified schematic of the Model 7035 multiplex banks is
shown in Figure 2-1. It is organized as nine independent
1 × 4 banks. Each bank has four inputs and one output. Two­pole switching is provided for each multiplexer input, with
HI and LO switched.

Bank A

Bank B

Bank C

Bank D

Bank E

Bank F

Bank G

Bank H

Bank I

Model 7035

1

1

1

1

1

1

1

1

1

4

4

4

4

4

4

4

4

4

Input (1 of 36)

HI
LO

Switching Topology

for all Channels

Figure 2-1

Model 7035 simplified schemati

HI

LO

Bank

2-1

Multiplexer Configuration

Bank A-I

HI

Out In

LO

Source or

Measure

Figure 2-2

Single-ended switching example

Typical multiplexer switching schemes

The following paragraphs describe some basic switching
schemes that are possible with a two-pole switching multi­plexer. These switching schemes include some various
shielding configurations to help minimize noise pick-up in
sensitive measurement applications. These shields are shown
connected to chassis ground. For some test configurations
shielding may prove to be more effective connected to circuit
common. Chassis ground is accessible at the rear panel of the
Model 7001/7002 mainframe.

Input 1-4

H

DUT

Optional

L

7035

single pathway as shown in Figure 2-2. The instrument is
connected to the output of one of the banks, and the DUT is
shown connected to one of the inputs for that bank.

Differential switching

The differential or floating switching configuration is shown
in Figure 2-3. The advantage of using this configuration is
that the terminals of the source or measure instrument are not
confined to the same pathway. Each terminal of the instru­ment can be switched to any available input in the test
system.

Shield

Single-ended switching

In the single-ended switching configuration, the source or
measure instrument is connected to the DUT through a

Bank A

HI

Out

LO

Out

Bank B

Source or

Measure

Figure 2-3

Differential switching example

Input 1-4

H

L

H

L

7035

In

DUT

In

Input 5-8

2-2

Source HI
Sense HI

Sense LO
Source LO

Bank A

Bank B

Out

Out

Multiplexer Configuration

Input 1-4

H
L

H
L

In

DUT

In

Source or

Measure

Figure 2-4

Sensing example

Sensing

Figure 2-4 shows how the multiplexer can be configured to
use instruments that have sensing capability. The main
advantage of using sensing is to cancel the effects of switch
card path resistance (<1 Ω ) and the resistance of external
cabling. Whenever path resistance is a consideration, sensing
should be used.

Output HI

Guard

Sense HI

Guard

7035

Input 5-8

SMU connections

Figure 2-5 shows how to connect a Keithley Model 236, 237,
or 238 Source Measure Unit to the multiplexer. By using
triax cables that are unterminated at one end, the driven
guard and chassis ground are physically extended all the way
to the card.

Bank A

Out

Out

Bank B

H
L

H
L

Input 1-4

In

DUT

In

Figure 2-5

SMU connections

Sense LO

Output LO

Output LO

236/237/238

7035

Input 5-8

WARNING: Hazardous voltages may be present on
GUARD. Make sure all cable shields are
properly insulated before applying power.

Triax

Cables (3)

2-3

Multiplexer Configuration

Multiplexer expansion

Larger multiplexers can be conf gured by externally connect­ing the individual Model 7035 multiplex banks using cus­tomer-supplied external jumpers. You can conf gure a
multiplexer as large as 1 × 36 (Figure 2-6).

Inputs

1

Bank A

4

1

Bank B

4

1

Bank C

4

1

Bank D

4

1

Bank E

4

1

Bank F

4

1

Bank G

4

1

Bank H

4

1

Bank I

4

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

Output A

2

Customer-supplied
external jumpers

2

2

Customer-supplied
external jumpers

2

2

Customer-supplied
external jumpers

2

2

Customer-supplied
external jumpers

2

2-4

Figure 2-6

Multiplexer expansion example

3

Card Connections

and Installation

Introduction

WARNING

The procedures in this section are in­tended only for qualified service person­nel. Do not perform these procedures
unless qualified to do so. Failure to rec­ognize and observe normal safety pre­cautions could result in personal injury
or death.

The information in this section is arranged as follows:

• Handling precautions  Explains precautions that
must be followed to prevent contamination to the card
assembly. Contamination could degrade the perfor­mance of the card.

• Multi-pin (mass termination) connections  Covers
the basics for connecting external circuitry to the con­nector card.

• Model 7035 installation and removal  Provides the
procedure to install and remove the card assembly from
the Model 7001/7002 mainframe.

Handling precautions

To maintain high impedance isolation, take care when
handling the card to avoid contamination from such foreign
materials as body oils. Such contamination can substantially
lower leakage resistances and degrade performance.

To avoid possible contamination, always grasp the relay card
and the connector card by the side edges or shields. Do not
touch the board surfaces or components. On connectors, do
not touch areas adjacent to the electrical contacts. Dirt
buildup over a period of time is another possible source of
contamination. To avoid this problem, operate the mainframe
and card assembly in a clean environment.

If a card becomes contaminated, it should be thoroughly
cleaned as explained in Section 5.

Multi-pin (mass termination) connections

Since connections to external circuitry are made at the 96-pin
male DIN bulkhead connector, there is no need to separate
the connector card from the relay card. If the connector card
is separated from the relay card, carefully mate them
together and install the supplied 4-40 screw to secure the
cards. Make sure to handle the cards by the edges and shields
to avoid contamination.

The connector will mate to a 96-pin female DIN connector.
Terminal identification for the DIN connector of the multi­pin connector card is provided by Figure 3-1 and Table 3-1
and can be identified in one of three ways:

1. Mux terminal consisting of banks A-I, channels 1-36.

2. Connector description consisting of rows a-c, pins 1-32.

3. Schematic and component layout designation consisting
of pins 1-96.

3-1

Card Connections and Installation

323130292827262524232221201918171615141312111098765432 1

c
b
a

View pin side
of connector

10
10a

34
2b

35
3b

36
4b

37
5b

38
6b

39
7b

40
8b

42
10b

Bank A

2

HI

2a

Channel 1

3
3a

LO

4

HI

4a

Channel 2

5
5a

LO

6

HI

6a

Channel 3

7
7a

LO

8

HI

8a

Channel 4

LO

HI

Output A

LO

11
11a

12
12a

Bank D

HI

Channel 13

LO

HI

Channel 14

LO

HI

Channel 15

LO

HI

Channel 16

LO

HI

Output D

LO

43
11b

44
12b

13
13a

14
14a

15
15a

16
16a

17
17a

18
18a

19
19a

20
20a

45
13b

46
14b

47
15b

48
16b

49
17b

50
18b

51
19b

52
20b

HI

LO

HI

LO

HI

LO

HI

LO

HI

LO

HI

LO

HI

LO

HI

LO

Bank B

Channel 5

Channel 6

Channel 7

Channel 8

Bank E

Channel 17

Channel 18

Channel 19

Channel 20

HI

Output B

LO

HI

Output E

LO

21
21a

22
22a

53
21b

54
22b

23
23a

24
24a

25
25a

26
26a

27
27a

28
28a

29
29a

30
30a

55
23b

56
24b

57
25b

58
26b

59
27b

60
28b

61
29b

62
30b

Bank C

HI

LO

HI

LO

HI

LO

HI

LO

Bank F

HI

LO

HI

LO

HI

LO

HI

LO

Channel 9

Channel 10

Channel 11

Channel 12

Channel 21

Channel 22

Channel 23

Channel 24

HI

Output C

LO

HI

Output F

LO

31
31a

32
32a

63
31b

64
32b

Bank G

65
1c

HI

Channel 25

66
2c

LO

67
3c

HI

Channel 26

68

LO

4c
69

HI

5c

Channel 27

70
6c

LO

71

HI

7c

Channel 28

72

LO

8c

1
1a

33
1b

HI

Output G

LO

73
9c

74
10c

95
31c

96
32c

75
11c

76
12c

77
13c

78
14c

79
15c

80
16c

81
17c

82
18c

Figure 3-1

Multi-pin connector card terminal identificatio

3-2

HI

LO

HI

LO

HI

LO

HI

LO

Bank H

Channel 29

Channel 30

Channel 31

Channel 32

41
9b

9
9a

HI

Output H

LO

83
19c

84
20c

85
21c

86
22c

87
23c

88
24c

89
25c

90
26c

91
27c

92
28c

Bank I

HI

LO

HI

LO

HI

LO

HI

LO

Channel 33

Channel 34

Channel 35

Channel 36

Output I

HI

LO

93
29c

94
30c