Keithley 7012-S, 7012-C Service manual

I

nstruction Manua

l

s

Models 7012-S and 7012-C

4 × 10 Matrix Card

Contains Operating and Servicing Information

7012-901-01 Rev. B / 11-93

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 fo r
the balance of the original warranty period, or at least 90 days.

LIMITATION OF WARRANTY

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 DAMA GES 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.

Keithley Instruments, Inc. • 28775 Aurora Road • Cle v eland, OH 44139 • 440-248-0400 • Fax: [phone] • http://www.k eithley.com

BELGIUM: Keithley Instruments B.V. Bergensesteenweg 709 • B-1600 Sint-Pieters-Leeuw • 02/363 00 40 • Fax: [phone]
CHINA: Keithley Instruments China
FRANCE: Keithley Instruments Sarl B.P. 60 • 3, allée des Garays • 91122 Palaiseau Cédex • 01 64 53 20 20 • Fax: [phone]
GERMANY: Keithley Instruments GmbH Landsberger Strasse 65 • D-82110 Germering • 089/84 93 07-40 • Fax: [phone]
GREAT BRITAIN: Keithley Instruments Ltd
INDIA: Keithley Instruments GmbH Flat 2B, WILOCRISSA • 14, Rest House Crescent • Bangalore 560 001 • 91-80-509-1320/21 • Fax: [phone]
ITALY: Keithley Instruments s.r.l. Viale S. Gimignano, 38 • 20146 Milano • 02/48 30 30 08 • Fax: [phone]
NETHERLANDS: Keithley Instruments B.V. Postbus 559 • 4200 AN Gorinchem • 0183-635333 • Fax: [phone]
SWITZERLAND: Keithley Instruments SA Kriesbachstrasse 4 • 8600 Dübendorf • 01-821 94 44 • Fax: [phone]
TAIWAN: Keithley Instruments Taiwan 1 Fl. 85 Po Ai Street • Hsinchu, Taiwan, R.O.C. • 886-3572-9077• Fax: [phone]

Y uan Chen Xin Building, Room 705 • 12 Y umin Road, De wai, Madian • Beijing 100029 • 8610-62022886 • F ax: 8610-62022892

The Minster • 58 Portman Road • Reading, Berkshire RG30 1EA • 0118-9 57 56 66 • Fax: [phone]

10/99

Models 7012-S and 7012-C Instruction Manual

©1991, Keithley Instruments, Inc.

All Rights Reserved

Cleveland, Ohio, U. S. A.

New Contact Information

Keithley Instruments, Inc.

28775 Aurora Road

Cleveland, OH 44139

Technical Support: 1-888-KEITHLEY

Monday – Friday 8:00 a.m. to 5:00 p.m (EST)

Fax: [phone]

Visit our website at http://www.keithley.com

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 7012-901-01) ........................................................................November 1991

Addendum A (Document Number 7012-901-02) ........................................................................January 1992

Revision B (Document Number 7012-901-01).........................................................................November 1993

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, for ensuring that the equipment is
operated within its specifications and operating limits, 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.

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, no conductive part of the circuit may be

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) 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. NEV ­ER connect switching cards directly to A C 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.

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. A good safety practice is to expect

that hazardous voltage is present in any unknown circuit bef ore
measuring.

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.

The instrument and accessories must be used in accordance with its
specifications and operating instructions or the safety of the equip­ment may be impaired.

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. Alw ays read the associated infor­mation very carefully before performing the indicated procedure.

The CAUTION heading in a manual explains hazards that could
damage the instrument. Such damage may invalidate the warranty.

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.

T o clean an 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. Products that consist of a circuit board with no case or
chassis (e.g., data acquisition board for installation into a computer)
should never require cleaning if handled according to instructions.
If the board becomes contaminated and operation is affected, the
board should be returned to the factory for proper cleaning/servic­ing.

Rev.10/99

7012 SPECIFICATIONS

MODEL 7012-S 4×10 Matrix with Screw Terminals.
MODEL 7012-C 4×10 Matrix with Mass Terminated Connector.
MATRIX CONFIGURATION: 4 rows by 10 columns. Jumpers can be

removed to isolate any row from the backplane.

CONTACT CONFIGURATION: 2-pole Form A (Hi, Lo).
CONNECTOR TYPE:

7012-S: Screw terminal, #16AWG maximum wire size, with .092 inch

O.D. 28 Conductors maximum. #22AWG typical wire size
with .062 inch O.D. 88 Conductor maximum.

7012-C: 96-Pin male Euro card connector. Mates to female twisted wire

cable, crimp or solder connector.

MAXIMUM SIGNAL LEVEL:

DC Signals: 110V DC between any two pins, 1A switched. 30VA

(resistive load).

AC Signals: 125V RMS or 175V AC peak, between any two pins,

1A switched, 60VA (resistive load).

COMMON MODE VOLTAGE: 175V peak, any pin to chassis.
CONTACT LIFE:

Cold Switching: 108 closures.
At Maximum Signal Levels: 105 closures.

7012 4x10 Matrix

7012 4x10 Matrix

CHANNEL RESISTANCE (per conductor): < 1Ω.

CONTACT POTENTIAL:

7012-S: < 500 nV per contact pair (Hi, Lo).

< 1.5 µV per single contact.

7012-C: < 1 µV per contact pair (Hi, Lo).

< 3 µV per single contact.

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

Path: >10
Differential: >10
Common Mode: >10

9

Ω, < 50 pF.

9

Ω, < 200 pF.

9

Ω, < 400 pF.

CROSS TALK (1MHz, 50Ω Load): < -40 dB.
INSERTION LOSS (50Ω Source, 50 Load): < 0.1dB below 1MHz, < 3 dB

below 2MHz.

RELAY DRIVE CURRENT (per relay): 16mA.
ENVIRONMENT:

Operation:0°C to 50°C, up to 35°C < 80% RH.
Storage: -25°C to 65°C.

Specifications subject to change without notice.

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HI

Matrix Crosspoint

LO

Matrix Crosspoint

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J
J

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Backplane

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J

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Backplane

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J

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Backplane

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Backplane

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Table of Contents

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

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

1.3 Warranty information..................................................................................................................................... 1-2

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

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

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

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

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

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

1.7.3 Instruction manual.................................................................................................................................. 1-3

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

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

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

2.2 Basic matrix configuration (4

2.3 Typical matrix switching schemes................................................................................................................ 2-3

2.3.1 Single-ended switching.......................................................................................................................... 2-3

2.3.2 Differential switching............................................................................................................................. 2-4

2.3.3 Sensing...................................................................................................................................................... 2-4

2.3.4 SMU connections..................................................................................................................................... 2-5

2.4 Matrix expansion............................................................................................................................................. 2-5

2.4.1 Two-card switching systems................................................................................................................. 2-5

2.4.2 Mainframe matrix expansion ................................................................................................................ 2-9

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

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

3.3 Connections...................................................................................................................................................... 3-1

3.3.1 Backplane row jumpers.......................................................................................................................... 3-2

3.3.2 Screw terminal connector card.............................................................................................................. 3-2

3.3.3 Multi-pin (mass termination) connector card..................................................................................... 3-4

3.4 Typical connection schemes .......................................................................................................................... 3-9

3.4.1 Single card system................................................................................................................................... 3-9

3.4.2 Two-card system..................................................................................................................................... 3-9

3.4.3 Two-mainframe system........................................................................................................................ 3-14

3.5 Model 7012 installation and removal......................................................................................................... 3-14

×

10) ............................................................................................................... 2-1

i

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

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

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

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

4.3.2 Front panel control.................................................................................................................................. 4-4

4.3.3 IEEE-488 bus operation........................................................................................................................... 4-4

4.4 Matrix switching examples ............................................................................................................................ 4-5

4.4.1 Thick film resistor network testing....................................................................................................... 4-5

4.4.2 Transistor testing................................................................................................................................... 4-10

4.5 Measurement considerations....................................................................................................................... 4-13

4.5.1 Path isolation.......................................................................................................................................... 4-13

4.5.2 Magnetic fields....................................................................................................................................... 4-14

4.5.3 Radio frequency interference............................................................................................................... 4-14

4.5.4 Ground loops ......................................................................................................................................... 4-14

4.5.5 Keeping connectors clean..................................................................................................................... 4-15

4.5.6 AC frequency response......................................................................................................................... 4-15

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

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

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

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

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

5.3.3 Matrix card connections ......................................................................................................................... 5-3

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

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

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

5.3.7 Path isolation tests................................................................................................................................... 5-7

5.3.8 Differential and common-mode isolation tests................................................................................... 5-9

5.4 Special handling of static-sensitive devices............................................................................................... 5-11

5.5 Principles of operation.................................................................................................................................. 5-12

5.5.1 Block diagram ........................................................................................................................................ 5-12

5.5.2 ID data circuits....................................................................................................................................... 5-13

5.5.3 Relay control........................................................................................................................................... 5-13

5.5.4 Relay power control.............................................................................................................................. 5-14

5.5.5 Power-on safeguard.............................................................................................................................. 5-14

5.6 Troubleshooting............................................................................................................................................. 5-15

5.6.1 Troubleshooting equipment................................................................................................................. 5-15

5.6.2 Troubleshooting access......................................................................................................................... 5-15

5.6.3 Troubleshooting procedure.................................................................................................................. 5-15

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

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

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

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

6.5 Component layouts and schematic diagrams ............................................................................................. 6-2

ii

List of Illustrations

Figure 2-1 Model 7012 simplified schematic.......................................................................................................... 2-1

Figure 2-2 Model 7001 analog backplane ............................................................................................................... 2-2

Figure 2-4 Single-ended switching example .......................................................................................................... 2-3

Figure 2-3 Matrix row connections to backplane .................................................................................................. 2-3

Figure 2-5 Differential switching example ............................................................................................................. 2-4

Figure 2-6 Sensing example...................................................................................................................................... 2-4

Figure 2-7 SMU connections..................................................................................................................................... 2-5

Figure 2-8 Two separate 4
Figure 2-9 Narrow matrix example (4
Figure 2-10 Wide matrix example (8

Figure 2-11 Mixed card type example....................................................................................................................... 2-9

Figure 2-12 Partial matrix expansion (8

×

10 matrices................................................................................................................. 2-6

×

20) ........................................................................................................... 2-7

×

10)................................................................................................................ 2-8

×

20) ........................................................................................................ 2-10

Figure 3-1 Backplane row jumpers.......................................................................................................................... 3-2

Figure 3-2 Screw terminal connector card.............................................................................................................. 3-3

Figure 3-3 Typical terminal block connections...................................................................................................... 3-3

Figure 3-4 Cable clamp for screw terminal connector card ................................................................................. 3-4

Figure 3-5 Multi-pin connector card terminal identification............................................................................... 3-5

Figure 3-6 Typical round cable connection techniques ........................................................................................ 3-7

Figure 3-7 Model 7011-MTR connector pinout...................................................................................................... 3-8

Figure 3-8 Model 7011-KIT-R (with cable) assembly............................................................................................ 3-8

Figure 3-9 Single card system example (multi-pin connector card) ................................................................. 3-10

Figure 3-10 Single card system example (screw terminal connector card)........................................................ 3-11

Figure 3-11 Two-card system example (multi-pin connector card).................................................................... 3-12

Figure 3-12 Two-card system example (screw terminal connector card) .......................................................... 3-13

Figure 3-13 Two-mainframe system example (multi-pin connector card) ........................................................ 3-15

Figure 3-14 Two-mainframe system example (screw terminal connector card)............................................... 3-16

Figure 3-15 Model 7012-S card installation in Model 7001 .................................................................................. 3-18

Figure 3-16 Model 7012-C card installation in Model 7001 ................................................................................. 3-19

Figure 4-1 Channel status display ........................................................................................................................... 4-2

Figure 4-2 Display organization for multiplexer channels .................................................................................. 4-3

Figure 4-3 Model 7012 programming channel assignments................................................................................ 4-3

Figure 4-4 Thick film resistor network testing....................................................................................................... 4-6

Figure 4-5 Four-terminal ohms measurements ..................................................................................................... 4-7

Figure 4-6 Voltage divider checks ........................................................................................................................... 4-9

Figure 4-7 Transistor testing................................................................................................................................... 4-10

Figure 4-8 DC parameter checks............................................................................................................................ 4-12

Figure 4-9 Common-emitter characteristics of an NPN silicon Transistor ...................................................... 4-13

Figure 4-10 Path isolation resistance........................................................................................................................ 4-13

Figure 4-11 Voltage attenuation by path isolation resistance .............................................................................. 4-13

Figure 4-12 Power line ground loops ...................................................................................................................... 4-15

Figure 4-13 Eliminating ground loops .................................................................................................................... 4-15

Figure 5-1 Path resistance testing............................................................................................................................. 5-3

Figure 5-2 Common-mode offset current testing................................................................................................... 5-5

Figure 5-3 Differential offset current testing .......................................................................................................... 5-5

Figure 5-4 Contact potential testing......................................................................................................................... 5-6

Figure 5-5 Path isolation testing (guarded) ............................................................................................................ 5-8

Figure 5-6 Differential isolation testing................................................................................................................. 5-10

Figure 5-7 Common-mode isolation testing......................................................................................................... 5-10

Figure 5-8 Model 7012 block diagram ................................................................................................................... 5-12

Figure 5-9 Start and stop sequences....................................................................................................................... 5-13

Figure 5-10 Transmit and acknowledge sequence................................................................................................. 5-14

List of Tables

Table 3-1 Mass termination accessories ................................................................................................................ 3-4

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

Table 5-2 Path isolation tests................................................................................................................................... 5-8

Table 5-3 Differential and common-mode isolation testing............................................................................. 5-11

Table 5-4 Recommended Troubleshooting Equipment.................................................................................... 5-15

Table 5-5 Troubleshooting procedure ................................................................................................................. 5-16

v/vi

1

General Information

1.1 Introduction

This section contains general information about the
Model 7012 4

There are two basic versions of this matrix card; the
Model 7012-S and the Model 7012-C. The Model 7012­S assembly consists of a screw terminal connector card
and the relay card. External test circuits are wired
directly to the screw terminals of the connector card.
Also available from Keithley is the Model 7012-ST. This
is an extra screw terminal connector card. With an extra
connector card, you can wire a second test system
without disturbing the wiring conÞguration of the Þrst
test system.

The Model 7012-C assembly consists of a multi-pin
(mass termination) connector card and the relay card.
External test circuit connections to the matrix 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 paragraph 1.9).

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

×

10 Matrix card.

1.4 Manual addenda

1.5 Safety symbols and terms

1.6 SpeciÞcations

1.7 Unpacking and inspection

1.8 Repacking for shipment

1.9 Optional accessories

1.2 Features

The Model 7012 is a two-pole, dual, 4
by 10 columns) matrix card. Some of the key features
include:

¥ Low contact potential and offset current for mini-

mal effects on low-level signals.

¥ The connector board detaches from the relay board

allowing easy access to the screw terminals (Model
7012-S) and backplane row jumpers.

¥ Backplane row jumpers. Cutting jumpers discon-

nects matrix rows from the Model 7001 analog
backplane.

×

10 (four rows

1.2 Features

1.3 Warranty information

1-1

General Information

1.3 Warranty information

Warranty information is located on the inside front
cover of this instruction manual. Should your Model
7012 require warranty service, contact the Keithley rep­resentative or authorized repair facility in your area for
further information. When returning the matrix card
for repair, be sure to Þll out and include the service
form at the back of this manual in order to provide the
repair facility with the necessary information.

1.4 Manual addenda

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

1.5 Safety symbols and terms

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

1.6 Specifications

Model 7012 speciÞcations are found at the front of this
manual. These speciÞcations are exclusive of the ma­trix mainframe speciÞcations.

1.7 Unpacking and inspection

1.7.1 Inspection for damage

The Model 7012 is packaged in a re-sealable, anti-static
bag to protect it from damage due to static discharge
and from 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 mainframe,
keep the card in the anti-static bag and store it in the
original packing carton.

The symbol on an instrument indicates that the
user 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 matrix card. Such dam­age may invalidate the warranty.

!

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.

1.7.2 Shipping contents

The following items are included with every Model
7012 order:

¥ Model 7012 4

¥ Model 7012 Instruction Manual

¥ Additional accessories as ordered

×

10 Matrix Card

1-2

General Information

1.7.3 Instruction manual

The Model 7012 Instruction Manual is three-hole
drilled so that it can be added to the three-ring binder
of the Model 7001 Instruction Manual. After removing
the plastic wrapping, place the manual in the binder
following the mainframe instruction manual. Note that
a manual identiÞcation tab is included and should pre­cede the matrix card instruction manual.

If an additional instruction manual is required, order
the manual package, Keithley part number 7012-901-

00. The manual package includes an instruction manu­al and any pertinent addenda.

1.8 Repacking for shipment

Should it become necessary to return the Model 7012
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 matrix card.

1.9 Optional accessories

The following accessories are available for use with the
Model 7012:

Model 7012-ST

is identical to the one provided with the Model 7012-S
assembly. An extra screw terminal connector card al­lows you to wire a second test system without disturb­ing the wiring conÞguration of the Þrst connector card.

Model 7011-KIT-R

96-pin female DIN connector that will mate directly to
the connector on the Model 7012-C or to a standard 96­pin male DIN bulkhead connector (see Model 7011­MTR). This connector uses solder cups for connections
to external circuitry. It includes an adapter for a round
cable and the housing.

Model 7011-MTC-2

sembly is terminated with a 96-pin female DIN connec­tor on each end. It will mate directly to the connector
on the Model 7012-C and to a standard 96-pin male
DIN bulkhead connector (see Model 7011-MTR).



This screw terminal connector card



This connection kit includes a



This two-meter round cable as-

¥ Write ATTENTION REPAIR DEPARTMENT on

the shipping label.

¥ Fill out and include the service form located at the

back of this manual.

Model 7011-MTR

connector 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.



This 96-pin male DIN bulkhead

1-3

2

Matrix Switching Basics

2.1 Introduction

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

2.2 Basic matrix conÞguration: Covers the basic 4

10 matrix conÞguration. The signiÞcance of the
backplane jumpers is also covered here.

2.3 Typical matrix switching schemes: Explains

some of the basic ways a matrix can be used to
source or measure. Covers single-ended switch­ing, differential (ßoating) switching, and sensing.

2.4 Matrix expansion: Discusses the various matrix

conÞgurations that are possible by using multi­ple cards.

2.2 Basic matrix configuration (4

A simpliÞed schematic of the Model 7012 matrix card
is shown in Figure 2-1. The card is conÞgured as a 4
10 matrix. Each of the 40 crosspoints is made up of a
two-pole switch. By closing the appropriate crosspoint
switch, any matrix row can be connected to any col­umn in the matrix.

×

10)

×

Column

110

23456789

1
2

Rows

3
4

Crosspoint (1 of 40)

HI

LO

Figure 2-1

Model 7012 simplified schematic

Backplane jumpers

Notice in Figure 2-1 there are four pairs of backplane
jumpers located on the relay card. With the jumpers in­stalled, the matrix card is connected to the analog back-

×

plane of the Model 7001 allowing matrix expansion
with a second 7001 card installed in the mainframe.
With the jumpers removed (cut), the matrix card is iso­lated from another card installed in the mainframe.

Backplane

Jumpers
(4 pairs)

To 7001

Analog

Backplane

2-1

Matrix Switching Basics

The three-pole analog backplane of the mainframe is
shown in Figure 2-2. It is through this analog back­plane where the rows of a Model 7012 matrix card in­stalled in one slot can be connected to the rows (or
banks) of a compatible card installed in the other slot of
the mainframe.

Figure 2-3 shows how each row of the Model 7012 is
connected to the backplane. Notice that, since the Mod­el 7012 is a two-pole card, there is no connection made
to the Guard terminal of the backplane. The Model
7012 is shipped from the factory with the backplane
row jumpers installed.

Model 7001

Card 1 Card 2

Row 1 or Bank A

H

Removing (cutting) the backplane jumpers isolates the
card from the backplane, and subsequently, any card
installed in the other slot. For information on removing
the jumpers, refer to paragraph 3.3.1.

NOTE

The Model 7001 does not provide an
analog backplane for the non-701X se­ries cards. As a result, anyone of these
cards installed in one slot in the main­frame is electrically isolated from any
card installed in the other slot. The only
way to connect a Model 7012 to one of
these cards is to wire them together.

Analog

Backplane

H

L

G

H

L

G

H

L

G

H

L

G

H = High

L = Low

G = Guard

Row 2 or Bank B

Row 3 or Bank C

Row 4 or Bank D

Row = Matrix Card (7012)
Bank = Mux Card (7011)

L

G

H

L

G

H

L

G

H

L

G

Figure 2-2

Model 7001 analog backplane

2-2

Matrix Switching Basics

7012

Matrix Row

(1 of 4)

H

L

H = High
L = Low
G = Guard

Backplane

Jumpers

Figure 2-3

Matrix row connections to backplane

Row Columns

HI

LO

7001

Analog

Backplane

H

L

G

2.3 Typical matrix switching schemes

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

2.3.1 Single-ended switching

In the single-ended switching conÞguration, the source
or measure instrument is connected to the DUT
through a single pathway as shown in Figure 2-4.

H

DUT

L

Optional

Shield

Source or

Measure

Figure 2-4

Single-ended switching example

7012

2-3

Matrix Switching Basics

2.3.2 Differential switching

The differential or ßoating switching conÞguration is
shown in Figure 2-5. The advantage of using this con­Þguration is that the terminals of the source or measure
instrument are not conÞned to the same matrix cross­point. Each terminal of the instrument can be connect­ed to any matrix crosspoint.

Rows Columns

HI

LO

Source or

Measure

2.3.3 Sensing

Figure 2-6 shows how the matrix card can be conÞg-
ured to use instruments that have sensing capability.
The main advantage of using sensing is to cancel the ef­fects of matrix card path resistance (<1
tance of external cabling. Whenever path resistance is a
consideration, sensing should be used.

H

L

DUT

H

L

7012

Ω

) and the resis-

Figure 2-5

Differential switching example

Source HI
Sense HI

Sense LO
Source LO

Source or

Measure

Figure 2-6

Sensing example

Rows Columns

H
L

DUT
H
L

7012

2-4

Matrix Switching Basics

2.3.4 SMU connections

Figure 2-7 shows how a Keithley Model 236, 237 or 238
Source Measure Unit could be connected to the matrix
card. 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.

2.4 Matrix expansion

With the use of additional matrix cards and main­frames, larger matrices can be conÞgured. Each Model

Rows Columns

Output HI

Guard

7001 Switch System mainframe will accommodate up
to two cards, and up to six mainframes can be connect­ed together. Thus, a switch system using as many as 12
cards in six mainframes can be conÞgured.

2.4.1 Two-card switching systems

Each Model 7001 Switch System mainframe can ac­commodate two cards to allow the following switching
conÞgurations.

H

L

Figure 2-7

SMU connections

Sense HI

Guard

Sense LO

Output LO

Output LO

Triax

Cables (3)

236/237/238

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

H

L

7012

DUT

2-5

Matrix Switching Basics

Separate switching systems

Two single-card systems can be conÞgured by remov­ing the backplane jumpers from one of the cards. The
two cards will be controlled by the same mainframe,
but they will be electrically isolated from each other.
Figure 2-8 shows an example using two Model 7012
matrix cards.

Card 1

7012

110

1

2

Rows

3

Columns

Narrow matrix expansion (4

A narrow 4 row

×

20 column matrix is conÞgured by

×

20 matrix)

simply installing two “as shipped” Model 7012s in the
Model 7001 mainframe. By leaving the backplane
jumpers installed, the rows of the matrix card installed
in slot 1 (CARD 1) are automatically connected to the
rows of the matrix card installed in slot 2 (CARD 2)
through the analog backplane. The 4

×

shown in Figure 2-9.

Card 2

7001

Analog

Backplane

110

7012

Columns

20 matrix is

1

2

Rows

3

4

4 x 10 Matrix

Figure 2-8

Two separate 4 × 10 matrices

4

4 x 10 Matrix

Jumpers

Removed

2-6

Matrix Switching Basics

Card 1

7012

110

1

2

Rows

3

4

Notes : Backplane jumpers on both
cards must be installed.

Columns

4 x 20 Matrix

Figure 2-9

Narrow matrix example (4 × 20)

Wide matrix expansion (8

A wide 8 row

×

10 column matrix is shown in Figure 2-

×

10 matrix)

10. For this conÞguration, the 10 columns of the two
matrix cards must be physically hard-wired together.
Also note that the backplane jumpers on one of the
cards must be removed in order to isolate the rows of
the two cards from each other.

Mixing card types

Different types of cards can be used together to create
some unique switching systems. For example, you

Card 2

7001

Analog

Backplane

11 20

7012

Columns

could have a Model 7012 matrix card installed in one
slot and a Model 7011 multiplexer card installed in the
other slot.

Figure 2-11 shows a possible switching system using a
matrix card and a multiplexer card. The backplane
jumpers for both the matrix and multiplexer cards
must be installed. This allows matrix rows to be con­nected to multiplexer banks. On the multiplexer card,
the bank-to-bank jumpers must be removed to main­tain isolation between matrix rows. See the instruction
manual for the Model 7011 for complete information
on the multiplexer card.

2-7

Matrix Switching Basics

External

Column

Jumpers

Card 1

7012

110

1

2

Rows

3

4

Columns

Jumpers

Removed

7001 Analog

Backplane

1

2

Rows

3

4

Figure 2-10

Wide matrix example (8 × 10)

7012

Card 2

8 x 10 Matrix

2-8

Matrix Switching Basics

110

1

2

Rows

3

4

Notes : 1. Models 7011 and 7012 backplane jumpers must be installed.

2. Model 7011 bank-to-bank jumpers must be removed.

Figure 2-11

Mixed card type example

Card 1

7012

Columns

4 x 10 Matrix

7001

Backplane

Card 2

7011

110

110

110

110

Inputs

Bank A

Bank B

Bank C

Bank D

Quad 1 x 10 Mux

2.4.2 Mainframe matrix expansion

Matrices using up to 12 matrix cards are possible by us­ing six Model 7001 mainframes together. Using 12
Model 7012 matrix cards provides 480 cross-points.

In general, connecting the rows of a card in one main­frame to the rows of a card in a second mainframe in­creases the column numbers of the matrix. For
example, if the rows of a 4
frame are connected to the rows of a 4
second mainframe, the resulting matrix would be 4

40. Paragraph 3.4.3 explains how to connect a test sys­tem using two mainframes.

Partial matrix implementation

A fully implemented matrix provides a relay at each
potential crosspoint. For example, a fully implemented
8

×

20 matrix utilizing four 4
160 crosspoints. A partially implemented 8
would contain fewer crosspoints.

×

20 matrix in one main-

×

20 matrix in a

×

10 matrix cards contains

×

20 matrix

An example of a partially implemented 8
shown in Figure 2-12. The partial matrix is still consid­ered 8

×

20, but contains only 120 crosspoints using
three Model 7012 matrix cards installed in two Model
7001 mainframes.

Matrix card #1 (7012 #1) installed in one of the slots of
the Þrst mainframe (7001 #1) provides a 4
The other slot of the Þrst mainframe should be left
empty. If another switching card is left in that slot,
make sure it is isolated from the analog backplane (i.e.
backplane jumpers removed). The two matrix cards
(7012 #2 and #3) installed in the second mainframe

×

(7001 #2) are conÞgured as a an 8

×

10 matrix as ex­plained in paragraph 2.4.2 (Wide Matrix Expansion).
Keep in mind that the rows of card #2 must be isolated
from the rows of card #3. This is accomplished by re­moving the jumpers on one of the two cards. Finally,
the partially implemented 8

×

20 matrix is realized by
externally hard-wiring the rows of card #1 to the rows
of card #2.

×

20 matrix is

×

10 matrix.

2-9

Matrix Switching Basics

An obvious advantage of a partial matrix is that fewer
matrix cards are needed. Another reason to use a par­tial matrix is to keep speciÞc devices from being con­nected directly to other devices. For example, a source
connected to rows 5, 6, 7 or 8 (Figure 2-12) cannot be

7001 #1

7012 #1

Columns

10

Rows

Rows

1

1
2
3
4

5
6
7
8

connected to a column of Model 7012 #1 with one “ac­cidental” crosspoint closure. Three speciÞc crosspoints
must be closed in order to route the source signal to a
column of card #1.

7001 #2

External

Row

Jumpers

11

7012 #2

Columns

20

Figure 2-12

Partial matrix expansion (8 × 20)

7012 #3

2-10

3

Card Connections & Installation

3.1 Introduction

WARNING

The procedures in this section are in­tended only for qualiÞed service per­sonnel. Do not perform these
procedures unless qualiÞed 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:

3.2 Handling precaution: Explains precautions that

must be followed to prevent contamination to the
matrix card assembly. Contamination could de­grade the performance of the matrix card.

3.3 Connection:

ternal circuitry to the two available connector
cards for the matrix; the screw terminal connec­tor card and the multi-pin connector card.

Covers the basics for connecting ex-

3.2 Handling precautions

To maintain high impedance isolation, care should be
taken when handling the relay card to avoid contami­nation from such foreign materials as body oils. Such
contamination can substantially lower leakage resis­tances, thus degrading performance.

To avoid possible contamination, always grasp the re­lay and connector cards 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 build-up over a period of time is another
possible source of contamination. To avoid this prob­lem, operate the mainframe and matrix card in a clean
environment.

If a card becomes contaminated, it should be thorough­ly cleaned as explained in paragraph 5.2.

3.4 Typical connection scheme: Provides some typi-

cal connection schemes for single card, two-card
and two-mainframe system conÞgurations.

3.5 Model 7012 installation: Provides a procedure to

install the matrix card assembly in the Model
7001 mainframe.

3.3 Connections

This paragraph provides the basic information needed
to connect your external test circuitry to the matrix. It
includes the removal/installation of the backplane row
jumpers on the relay card, and detailed information on
the two available connector cards.

3-1

Card Connections & Installation

WARNING

The following connection informa­tion is intended to be used by quali­Þed service personnel. Failure to
recognize and observe standard safe­ty precautions could result in person­al injury or death.

3.3.1 Backplane row jumpers

The Model 7001 mainframe has an analog backplane
that allows the rows of a Model 7012 matrix to be inter­nally connected to a compatible switching card in­stalled in the other slot (see paragraph 2.4.1 for details).

The backplane row jumpers for the matrix card assem­bly are located on the relay card as shown in Figure 3-

1. The card is shipped from the factory with the jump­ers installed.

2. Physically remove a cut jumper by unsoldering it
from the PC board.

3. Install a new #22 AWG jumper wire (Keithley P/N
J-15) and solder it to the PC board.

4. Remove the solder ßux from the PC board. The
cleaning procedure is explained in paragraph 5.2.

7012 Relay Card

Row 1

Row 2

Row 3

Row 4

H

L

H

L

H

L

H
L

Jumper removal

Perform the following steps to remove backplane row
jumpers:

1. If mated together, separate the relay card from the
connector card by removing the mounting screw
and then pulling the two cards away from each
other. Remember to only handle the cards by the
edges and shields to avoid contamination.

2. Use Figure 3-1 to locate the jumper(s) that are to be
removed.

3. It is not necessary to physically remove the jump­ers from the PC board. Using a pair of wire cutters,
cut one lead of each jumper.

Jumper installation

Referring to Figure 3-1 for jumper locations, perform
the following steps to install backplane row jumpers:

1. If mated together, separate the relay card from the
connector card by removing the mounting screw
and then pulling the two cards away from each
other. Remember to only handle the cards by the
edges and shields to avoid contamination.

Jumpers

Figure 3-1

Backplane row jumpers

3.3.2 Screw terminal connector card

The screw terminal connector card is shown in Figure
3-2. Connections are made directly to the screw termi­nals of the four terminal blocks. Each screw terminal
will accommodate #16-22 AWG wire.

Wiring procedure

Perform the following procedure to wire circuitry to
the screw terminal connector card:

WARNING

Make sure all power is off and any
stored energy in external circuitry is
discharged.

3-2