Model 7071 General Purpose Matrix Card Instruction Manual

Model 7071 General Purpose Matrix Card Instruction Manual
Model 7071 General Purpose Matrix
Instruction
Manual
Contains Operating
Publication
Document
Date: June 1991
Number:
7071-901-01
and Servicing
Rev. D
Information
Card
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 wannty, write or call your local Kcithley representative, or contact Keithley headquarters in Cleveland, Ohio. You
will bc 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 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 leak
age, 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 SUALL 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
STATEMENT OF CALIBRATION
This instrument has been inspected and tested in accordance with specifications published by Keithley Instruments, Inc,
The accuracy and calibration of this instrument me traceable to the National Bureau of Standards through equipment which is calibrated at planned intervals by comparison to certified standards maintained in the Laboratories of Keithley Instruments, Inc.
Instruction Manual
Model 7071
General Purpose Matrix Card
01984 Keithley Instruments,
Inc.
Instruments Division
Cleveland, Ohio, U.S.A.
Document Number: 7071-901-01
Safety Precautions
The following safety precautions should be obsewed before using
this product and any associated instrumentation. Although some in~trument~ and accessories would nomudly bc used with non-hazardous voltages, there are situations where hazardous conditions
may be present.
This product is intended for “se by qoalilied personnel who recognize shock hazards and are familiar with the safety precautions required to avoid porsiblc 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 “se
and maintenaocc of equipment, for ensuring that the equipment is
operated within its specifications and operating limits. and for ensuring that operators are adequately trained.
Operators “se the product for its intended function. They most be
trained in electrical safety procedorcs and proper “se of the instrument. They must be pro&ted from electric shock and contact with
hazudous live circuits.
Maintenance personnel perform routine procedures on the product
to keep it operating, for example, setting tbc line voltage or replacingconsumable materials. Maintenance procedures aredescribed in
the manual. The procedures explicitly state if tbc operator may perform them. Otherwise, they should be performed only by service
personnel.
Service personnel arc trained to work on live circuits, and perform
safe installations and repairs of products. Only properly trained ser.
vice personnel may perform installation and sewicc 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. A good safety practice is to expect
that hazardous voltage is present in any unknown circuit before
measuring.
Users of this product most be protected from electric shock at all
times. The responsible body most ensure that users arc prcvcnlcd
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 10 protect tb~n~s~l~~s
from the risk of electric shock. If the circuit is capable of operating
at or above 1000 votts, no conductive part of the circuit may be
exposed.
As described in tbc lntcmational Electrotechnical Commission
([EC) Standard IEC 664, dig&l multimeter measuting circuits
(e.g., Kcithley Models 175A. 199. 200% 2001. 2002, sod 2010) are
Installation Category II. All other iostmmcots signal tuminals arc
Installation Category I sod must not be connected to maios.
Do not connect switching cards directly to unlimited powcrcircuits.
They are intended to hc used with im~daoce limited sour~cs.
NEVER connect switching cards directly to AC mains. When cons
nccth~g SOU~CCS
to switching cards, insult protoctivc devices 1” lim
it fault torrent and voltage to the card.
Before operating an iostromcnt, make sure the line cord is connectcd to a properly grounded power reccptaclc. Inspcc~ the connecting
cables. test leads, ;ind jumpers for possible war. cracks, or breaks
before each use.
For maximom safety. do nut 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 bcforc: connecting or disconnecting cables or jumpy
crs, installing or removing switching cards. or making intcnul
changes, such as installing or removing jumpers.
Do not touch any “bjcct that could provide a curreot path to the
comm”” side of the circuit under test or power line (earth) ground.
Always make mea~~ren~cnts with dry hands while stmding on n
dry, insulated surface capable of withstanding the voltage being
measured.
The instrument and accessories must be used in accordance with its
specitications and operating instructions or the safety of the equipment may be impaired.
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.
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.
The CAUTION heading in a manual explains hazards that could
damage the instrument. Such damage may invalidate the warranty.
when fuses are used in a product, replace with same type and rating
for continued protection against fin: hazard.
Before performing any maintenance, disconnect the line cord and
all test cables.
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.
screw is present, connect it to safety earth ground using the
[email protected]
wire recommended in the user documentation.
symbol on an instrument indicates that the uscr should rem A
fer to the operating instructions located in the manual.
symbol on an instrument shows that it can source or mcaThen
sum 1003 volts or more, including the combined effect of normal
and common mode voltages. Use standard safety precautions to
avoid personal contact with these voltages.
Instrumentation and accessories shall not be connected to humans.
To maintain protection from electric shock and fire, replacement
components in mains circuits, including the powcr transformer, test
leads, and input jacks, must be purchased from Keithley Instnmerits. Standard fuses, with applicahlc 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 sclead 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
Keithlcy Instruments office for information.
To clean an instrument, use a damp cloth or mild, water based
cleaner. Clean the exterior of the insrmment only. Do not apply
cleaner directly to the instrument or allow liquids to enter or spill
on the instmmcnt. 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 instmctions. If tbc board becomes contaminated and operation is affccted, the board should be returned to the factory for proper
cleaning/servicing.
Rev. IO/99
SAFETY PRECAUTIONS
The following
malts.
safety precautions
should be observed before using the Model 7071 and the associated instru-
This matrix card is intended for use by qualified personnel who recognize shock hazards and are familiar
with the safety precautions required to avoid possible injury. Read over this manual carefully before using
the matrix card.
ALWAYS remove power from the entire system (Model 707, test instruments,
capacitors before doing any of the following:
1. Installing
or removing
DUT, etc.) and discharge any
the matrix card from the mainframe.
2. Connecting or disconnecting cables from the mahix card. The pins of the Model 7078~MTC cable connectors are easily accessible making them extremely hazardous to handle while power is applied.
3. Making internal changes to the card (such as removing or installing
minal blocks).
Exercise extreme caution when
may be present on the fixture
states that a shock hazard exists
safety practice is to expect that
jumpers and quick-disconnect
ter-
a shock hazard is present at the test fixtire. User-supplied lethal voltages
or the connector jacks. The American National Standards Institute (ANSI)
when voltage levels greater than 30V Rh4S or 42.4V peak are present. A good
hazardous voltage is present in any unknown circuit before measuring.
Do not exceed ZOOV between any two pins or between any pin and earth ground
Inspect the connecting
cables and test leads for possible wear, cracks, or breaks before each use.
For maximum safety, do not touch the test fixture, test cables or any instruments
the circuit under test.
while power is applied to
Do not touch any object which could provide a current path to the common side of the circuit under test or
power line (earth) ground.
Do not exceed the maximum
section of this manual.
signal levels of the test fixture, as defined in the specifications
and operation
Do not connect the matrix card directly to unlimited power circuits. This product is intended to be used with
impedance limited sources. NEVER connect the matrix card directly to ac mains.
When connecting
sources, install protective
devices to limit fault current and voltage to the card
The chassis connections on the PC board (located behind the front panel of the matrix card) must only be
used as shield connections for measuring circuits, NOT as safety earth ground connections.
SPECIFICATIONS
MATRIX CONFIGURATION:
8 rows by 12 columns.
CROSSPOINT CONFIGURATION:
Spole Form A.
CONNECTOR TYYPE:Quick disconnect using
38 pin umnectom or screw temals
(HI,
LO, Guard).
MAXIMUM SIGNAL LEVEL:. 2CQV.lA
cany/O.SA switched. 1OVA peak (resistive
load).
COMMON MODE VOLTAGE: 2ooV maximum
between any 2 pins or chassis.
CONTACT LIFE:
Cold Switching: 10’ closures.
At M&mum Sigrul Level: 10’ closures.
PATH RESISTANCE ,per conductor): <0.50
initial, <1.5ll at end of contact life.
CONTACT POTENTIAL: <5pV per aosspoint
(HI to LO).
OFFSET CURRENT: <lOOpA.
ISOLATION:
Path WvIIiz, 1MO load): > 1OWo. clOpF.
>4OdB.
DifferentfaI: 109, 45pF nominal.
Common Mode: lO’R, 165pF nominal.
INSERTION LOSS (YMHz, 50” source, IMR
load): O.ldB tvoicaf.
,.
SdB BANDWIDTH (IMfl load): 5MHz typical.
RELAY DRIVE CURRENT (Per crosspoint):
15mA.
RELAY SE’ITLING TIME: <3mr.
ENVIRONMENT:
Opedng: O” to WC, up to 35’C at 70% R.H.
Storage: -25 to +65-C.
ACCESSORY SUPPLIED: Instnxtion manual
ACCESSORIES AVAILABLE:
Model 7078~CIT: Contact Insertion and
Extraction Tools
Model 707%HCT: Hand Crimping Tool
Model 707SWT: Connector Kit.
Model 707EMTC: Mass Terminated Cable
Assembly, 6m (20 ft.)
Contains information on Model 7071 features, specifications, and accessories.
SECTION 1
General Information
Details installation of the Model 7071 General Purpose
Matrix Card within the Model 707 Switching M&ix,
covers card connections, and also discusses basic m&ix
configurations
and matrix expansion.
SECTION 2
Gives two typical applications for the Model 7071, including thick film resistor network testing and transistor testing.
SECTION 3 ’
Contains performance verification procedures, troubleshooting information and principles of operation for
the matrix card.
SECTION 4 /
Lists replacement parts, and also includes component
layout and schematic drawings for the Model 7071.
Operation
I
Applications
Service Information
SECTION 5 /
Replaceable
Parts i
Table of Contents
SECTION
1.1
1.2
1.3
1.4
1.5
1.6
1.7
1.7.1
1.7.2
1.73
1.8
1.9
i-General
Information
INTRODUCIION
FFXURES
WARRANTY INFORMATION
MANUAL ADDENDA
SAFETY SYMBOLS AND TERMS ............
SPECIFICATIONS ...........................
UNPACKING and INSPECTION ..............
.........
Inspection for Damage ......
.........
Shiuuine Contents .........
.........
Inst%ti;n
Manual
.........
REPACKING FOR SHIPMENT
.........
OPTIONAL ACCESSORIES..
.........................
.........................
.........................
.........................
.........................
.........................
.........................
.........................
..........................
.........................
.........................
.........................
1-l
1-l
1-l
1-l
l-1
l-1
1-l
l-1
1-2
1-2
1-2
1-2
SECTION 2-Operation
2.1
2.2
2.3
2.4
2.4.1
2.4.2
2.4.3
2.4.4
2.5
2.5.1
2.5.2
2.5.3
2.6
2.6.1
2.6.2
2.6.3
2.6.4
2.7
2.7.1
2.7.2
2.7.3
...........
........................
..........
INTRODUCITON
...........
........................
..........
HANDLING
PRECAUTIONS
CARD INSTALLtUlON
AND REMOVAL ......
......
BASIC MAIRIX CONFIGURATIONS
..........
......
.,....
Single-Ended Switching
....................
Differential Switching
.......................
......
......
Guarding ...................................
......
......
Sensing ....................................
CONNECTION
METHODS ....................................................................
Connection Methods Using Mass Terminated Cable (Model 7U78MTC). ..........................
Direct Connection Method ..................................................................
Connection Method Using Connector Kit (Model 7078~KIT) ....................................
........................................................................
MATRIXEXI’ANSION
.................................................................
Narrow Matrix Expansion..
WideMatrixExpansion
.....................................................................
PartiaIMatrixImplementation
................................................................
Mainframe MahixExpansion
.................................................................
TYT’ICAL CONNECI-ION
SCHEMES ...........................................................
Single Card System .........................................................................
Multiple Card System .......................................................................
Multiple Mainframe System ..................................................................
SECTION
3.1
3.2
3.2.1
3.2.2
3.2.3
3.3
3.3.1
3.3.2
2-l
2-l
2-l
2-2
2-b
2-6
2-6
2-6
2-8
2-9
!-15
!-15
t-18
98
!-19
; -20
2-20
2:-21
2:-21
2,722
2-22
‘
3-Applications
............................................................................
INTRODUCTION
THICK FILM RESISTOR NETWORK TESTING .................................................
Four-terminal Ohms Measurements ...........................................................
Voltage Divider Checks ......................................................................
Current Shunt Checks .......................................................................
TRANSISMR
TESTING .......................................................................
Current Gain Checks .......................................................................
I, and V., Measurements ...................................................................
3-l
31
3-2
33
3-5
3-5
3-7
37
SECTION 4-Service
4.1
4.2
4.3
4.4
4.4.1
4.4.2
4.4.3
4.4.4
4.4.5
4.4.6
4.4.7
4.5
4.5.1
4.5.2
4.5.3
4.6
4.7
4.7.1
4.7.2
4-l
4-1
4-l
42
43
43
43
45
4-7
49
411
413
4-W
414
414
414
415
415
415
INTRODUCITON
..............................................................................
HANDLING
AND CLEANING
PRECAUTIONS ..................................................
RELAY TEST PROGRAM SETUP ................................................................
PERFORMANCE VERIPICATION
...............................................................
EnvhonmentaI
Conditions
....................................................................
Recommended Equipment ....................................................................
Path Resistance Tests .........................................................................
Offset Current Tests.. ........................................................................
Contact Potential Tests ........................................................................
Path Isolation Tests ...........................................................................
..
DtierenhaI
and Common Mode Isolation Tests .................................................
PRINCIPLESOF
OPERATION .................................................................
Card Identification ...........................................................................
switching
circuitry ..........................................................................
Power Up Sateguard .........................................................................
SPECL4L HANDLING
OF STATIC-SENSITIVE
DEVICES .........................................
.........................................................................
TROUBLESHOOTING
Recommended Equipment
...................................................................
Troubleshooting
Procedure ...................................................................
SECTION
5.1
5.2
5.3
5.4
5.5
Infmmation
S-Replaceable
Parts
INTRODUCIlON
..............................................................................
PARTS LISTS .....................................................................
ORDERING INFORMATION..
..................................................................
FACTORY S?ZR\JICE ............................................................................
COMPONENT
LAYOUT AND SCHEMATIC DIAGRAM.
..........................................
: ............
5-l
5-l
5-l
5-l
5-l
List of Tables
SECTION
2-l
2-2
2-3
2-4
2-5
Column Number Assignments ..................................................................
Model 7071 Available Accessories ...............................................................
............................................................
Model 7078 MTC Wire Identification
Narrow Matrix Expansion* .....................................................................
Wide Matrix Expansion* .......................................................................
SECTION
41
42
4-3
4-4
45
2-Operation
4-Service
2-2
Z-10
Z-12
Z-18
2-19
Information
Verification Equipment .........................................................................
Path Isolation Tests ............................................................................
Differential and Common Mode Isolation Test ...................................................
Recommended Troubleshooting
Equipment ......................................................
Troubleshooting
Summary* ....................................................................
44
4-10
411
4-15
4-15
iii/iv
List of Illustrations
SECTION 2-Operation
2-l
2-2
2-3
2-4
2-5
2-6
2-7
2-8
2-9
2-m
2-u
2-w.
2-u
2-14
2-15
2-16
2-v
2-18
2-19
2-20
2-21
2-23
2-22
........................................................................
MatrixCard
Installation
CableClamp
Assembly .........................................................................
Simplified Schematic of Model 7071 .............................................................
Single-Ended Switching Example (Guard Used as Shield) .........................................
Differential Switching Example (Shielded) ........................................................
Driven Guard Example (Shielded) ...............................................................
....................................................................
SensingExample(Shielded)
Connections Using two Model 70%MTC Cables .................................................
Connecting PlugtoRectacle
....................................................................
Receptacle Contact Assignments ................................................................
Connections Using One Model 7078-MTC Cable Cut in Half ......................................
TerminalBlock
Connections ....................................................................
.............................................................................
CablePreparation
Connecting Beldon 9734 Cable to Receptacle .....................................................
Cable Positions ...............................................................................
Narrow Matrix Example (8 x 36) (Backplane Jumpers Not Removed) ..............................
Two 8 x 36 Matrices Using Six Model 7071s. ....................................................
Wide Matrix Example (16 x 24) ................................................................
Partial Matrix Expansion (16 x 24). .............................................................
Single Card System Example. ..................................................................
MultipleCard
SystemExample .................................................................
Plug Contact Assignments .....................................................................
Multiple Mainframe Example ..................................................................
2-3
2-4
2-5
2-6
2-7
2-7
2-8
2-11
2-U
2-U
2-14
2-15
2-16
2-V
2-V
2-18
2-19
2-20
2-21
2-22
2-23
2-25
2-24
SECTION 3-Applications
3-l
3-2
3-3
3-4
3-5
3-6
3-7
El
Thick Film Resistor Network Testing .............................................................
.................................................................
4TerminalOhmsMeasurements
Voltage Divider Checks .........................................................................
Current Chunt Checks.. .......................................................................
Transistor Testing ..............................................................................
Transistor Current Gain Checks .................................................................
Common-Emmitter
Characteristics of an NPN Silicon Transistor. ...................................
....................................................................
Transistor IE Measurements
..................................................................
Transistor VgE Measurements.
SECTION 4-Service
41
42
43
4-4
45
46
47
48
49
410
3-l
3-2
3-4
3-6
3-7
3-8
3-9
510
3-11
Information
Relay Test Setup ...............................................................................
PathResistanceTesting
.........................................................................
Differential Offset Current Testing ...............................................................
Common Mode Offset Current Testing ...........................................................
Contact Potential Testing ........................................................................
Path Isolation Testing (Guarded). ...............................................................
Differential Isolation Testing ....................................................................
Common Mode Isolation Testing ...............................................................
IDD~
Tuning Diagram .......................................................................
................................................................
Receptacle Contact Identification
42
44
46
4-7
48
410
4-U
4-U
414
416
v/vi
SECTION 1
General Information
1.1 INTRODUCTION
This section contains general information about the Model
7071 General Purpose Matrix Card and is arranged in the
following manner:
1.2
1.3
1.4
1.5
1.6
1.7
1.8
1.9
Features
Warranty Information
Manual Addenda
Safety Symbols and Terms
Specifications
Unpacking and Inspection
Repacking for Shipment
Optional Accessories
The Model 7071 is a general purpose, three-pole 8 x 12
(8 row by I2 column) matrix card. Some of the key features
include:
. Guard capability. Each HIILQ path pair on the PC board
is surrounded by a third path that can be used for
guarding.
l Low
contact potential and offset current for minimal
effects on low-level signals.
l Quick disconnects
using the “rack and panel” receptacles
on the rear panel or terminal blocks on the PC board.
INFORMATION
Warranty information is located on the inside front cover
of this instruction manual. Should your Model 7071 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 fill out and include the service form at the back of this
manual in order to provide the repair facility with the
necessary information.
1.4 MANUAL
1.5 SAFETY
SYMBOLS
AND TERMS
The following symbols and terms may be found on an instrument or used in this manual.
The symbol A
on an instrument indicates that the user
should refer to the operating instructions located in the
instruction manual.
The symbol &
on an rnshument
shows that high
voltage may be present on the terminal(s). Use standard
safety precautions to avoid personal contact with these
voltages.
1.2 FEATURES
1.3 WARRANTY
with the unit. Be sure to note these changes and incorporate them into the manual.
ADDENDA
Any improvements or changes concerning the matrix card
or manual will be explained in an addendum included
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.
1.6 SPECIFICATIONS
Model 7071 specifications may be found at the front of this
manual. These specifications are exclusive of the matrix
mainframe specifications.
1.7 UNPACKING
AND INSPECTION
1.7.1 Inspection
for Damage
The Model 7071 is packaged in a resealable, 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.
1-l
GENERALINFORMATION
Handling
Precautions:
l
l
1. Always grasp the card by the handle and side edges.
Do not touch the edge connectors and do not touch
board surfaces or components.
2. When not installed in a Model 707 mainframe, keep the
card in the anti-static bag and store 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.
l
Advise as to the warranty status of the matrix card.
Write ATTENTION REPAIR DEPARTMENT on the ship
ping label.
Fill out and include the service form located at the back
of this manual.
1.9 OPTIONAL
The following
Model 7071.
Model
lf you are going to install the card in the Model 707 mainframe at this time, be sure to follow the additional handling precautions explained in paragraph 2.2
1.7.2 Shipping
l
l
l
Tools
707&HCT Hand Crimping
Tool
The Model 7U7&HCT is used to attach wire crimp tail contacts to #l8 to %26 AWG stranded wire.
Manual
The Model 7071 Instruction Manual is three-hole drilled
so that it can be added to the three-ring binder of the
Model 707 Switching Matrix Instruction
Manual. After
removin
the plastic wrapping, place the manual in the
binder a8 er the mainframe instruction manual. Note that
a manual identification 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 7071-901-00. The
manual package includes an instruction manual and any
pertinent addenda.
FOR SHIPMENT
Should it become necessary to return the Model 7071 for
repair carefully pack the unit in its original packing carton or the equivalent,
and include
the following
information:
l-2
and Extraction
with every Model 7Ril
Model 7071 General Purpose Matrix Card.
Model 7071 Instruction Manual.
Additional Accessories as ordered. Note that the Model
7VBMTC may be shipped in a separate packing carton.
1.8 REPACKING
Contact Insertion
Contents
items are included
1.7.3 Instruction
accessories are available for use with the
The Model 707%CIT contains an insertion tool that is used
to insert wire crimp tail contacts into “rack and panel”
plugs and receptacles. Conversely, the extraction tool is
used for the removal of the contacts.
Model
The following
order:
XIB-CIT
ACCESSORIES
Model
7U784UT Connector
Kit (Plug)
The Model 7UBKlT contains the parts to assemble one
“rack and panel” plug. This plug will mate to either the
ROWS or COLUMNS receptacle on the rear panel of the
card. Parts contained in the kit indude the phzg, plug housing and 40 wire crimp tail contacts.
Model
7U78-MTR Connector
Kit (Receptacle)
The Model 7RBMTR contains the parts to assemble and
mount one “rack and panel” receptade. Parts contained
in the kit indude the receptade, 40 wire crimp tail conhardware.
tacts, and mounting
Model
7lVEMTC-5
Mass Terminated
Cable Assembly
The Model iQ%M’lC-5 is a 5foot (1.5 meter), 36-conductor
cable terminated with a “rack and panel” plug on both
ends. This cable connects to either the ROWS or COL
UMNS receptade on the rear panel of the card. This cable
is commonly cut in half to provide two separate cables.
The cables can then be used to connect to both the ROWS
and COLUMNS receptades. The unterminated ends of the
cables are then connected to instrumentation
and DUTs.
Model
7078~MTC-20 Mass Terminated
Cable Assembly
This cable assembly
is the sames as the Model
707&m-5
except that it is 20 feet (6 meters) in length.
CS-570-3 Quick Disconnect
Terminal
Block
Three-terminal block accomodating up to 16 AWG wires.
Mates to matrix board pin terminals.
l-3114
SECTION 2
Operation
2.1 INTRODUCTION
This section contains information on aspects of matrix card
operation and is arranged as follows:
2.2 Handling Precautions: Details precautions that should
be observed when handling the matrix card to ensure
that its performance
is not degraded
due to
contamination.
2.3 Card Installation
and Removal: Covers the basic procedure for installing and removing the card from the
Model 707 Matrix.
2.4 Basic Matrix Configurations:
Explains some the basic
ways that a matrix can be used to source or measure.
Covers single-ended switching, differential (floating)
switching, sensing, shielding, and guarding.
2.5 Connections:
Discusses the various methods and
techniques that can be used to connect DUB and instrumentation to the matrix card.
2.6 Matrix Expansion: Discusses the various matrix configurations that are possible by using multiple cards.
The significance of the Model 707 backplane row
jumpers on matrix configurations is also covered here.
2.7 Typical Connection Schemes: Provides examples of extemal connections for single card, multiple card and
multiple mainframe systems.
2.2 HANDLING
CAUTION
Do not store the csrd by leaning it against an
object (such as a wall) with Its edge connectors
in contact with a contaminated surtace (such
as the floor). The edge connectors will become
contaminated, and tapes and solder connections on the PC board may break as the card
bends. ALWAYS store the card (in its anti-static
bag) in the original shipping carton.
Dirt build-up over a period of time is another possible
source of contamination.
To avoid this problem, operate
the mainframe
and matrix card only in a clean
environment.
If the card becomes contaminated, it should be thoroughly
cleaned as explained in paragraph 4.2.
2.3 CARD INSTALLATION
AND REMOVAL
Connections to the matrix card make it awkward to install/
remove the card in the mainframe. Thus, it is advisable
to install the card and then make connections to it. Conversely, cables and wires should be disconnected before
removing the card from the mainframe.
Referring to Figures Z-1 and 2-2, perform the following prw
cedure to install the Model 7071 matrix card in the Model
m
PRECAUTIONS
To maintain high impedance isolation, care should be
taken when handling the matrix card to avoid contamination from such foreign materials as body oils. Such contamination can substantially
lower leakage resistances,
degrading performance.
To avoid possible contamination, always grasp the card by
the handle and side edges. Do not touch the edge connectors of the card and do not touch board surfaces or components. On “rack and panel” connectors and quickdisconnect terminal blocks, do not touch areas adjacent
to the electrical contacts.
1. Turn the Model 707 off.
2. Select a slot in the mainframe and remove the cover
plate. The cover plate is fastened to the mainframe
chassis with two screws. Retain the cover plate and
screws for future use.
3. With the relay side of the matrix card facing towards the
fan, feed the card into the slot such that the top and
bottom card edges seat into the the card edge guides
of the mainframe. Slide the matrix card approximately
% of the way into the mainframe.
4. If using quick-disconnect terminal blocks to make connections, perform the following steps. Otherwise, proceed to step 5.
2-l
OPERATION
WARNING
To avoid electrical shock which could result in
injury or death, make sure all power is off and
stored energy in external circuitry is dischaged before making any connections to the matrix
card.
A. There are two cable clamps on the rear panel of the
matrix card that serve as strain reliefs for terminal
block wires. Loosen the two screws of each cable
clamp and remove the top half of each clamp.
B. Install the pre-wired terminal blocks (see paragraph
2.52) on the matrix card. Make sure the pins on the
card are properly mated to the terminal blocks.
C. Route the wires through the rear panel cable clamps.
Make sure there is some slack in the wires between
the terminal blocks and the clamps before tightening
the clamps.
5. Slide the matrix card all the way into the mainframe and
tighten the two spring loaded panel fastenters.
6. To remove the card from the mainframe make sure the
Model 707 is off, power is removed from external circuitry, and then reverse the above procedure.
2.4 BASIC MATRIX CONFIGURATIONS
A simplified schematic of the Model 7071 8 x I2 matrix
card is shown in Figure 2-3. Each of the 96 crosspoints is
made up of a three-pole switch. In this simple configuration, any row can be connected to any column by closing
the appropriate crosspoint switch. The columns of every
Model 7071 matrix card are numbered 1 through l2.
However, the actoal column numbers of the matrix are
determined by which mainframe slot the card is installed
in. For example, the columns of a matrix card installed in
slot 4 of the mainframe are numbered 37 through 48. Column number assignments for all six mainframe slots are
listed in Table 2-l.
Table 2-1. Column
WARNING
The mounting screws must be secured to ensure a proper chassis ground connection betwsen the card and the mainframe. Failum to
properly secure this ground connection may
result in petsonal injury or death due to electric shock.
NOTE
If using the terminal blocks, leave enough slack
in the external cabling so that the card can slide
out far enough to gain access to the connections.
2-2
Number
Assignments
Matrix
CoIumn Numbers
7Wl Card Location
I
OPERATION
MOUNTING SCREWS
Figure 2-l. Matrix
Card Installation
2-3
OPERATION
Top hail of Cable Clamp
Figure 2-2. Cable Clamp Assembly
2-4
OPERATION
Column
I
lI
I
I
1
2
3
4
5
6
7
6
9
10
11
12
'
I
I
A
A
/I
B
B
c
I
I
1
Row
D
I
E
/
F
I
G
G
I
H
L-------------
Figure 2-3. Simplified
Schematic
of Model 7071
2-s
OPERATION
2.4.1 Single-Ended
Switching
In the single-ended switching configuration, the source or
measure instrument is connected to the DUT through a
single pathway as shown in Figure 2-4. Note that in the
illustration
that the matrix card guard (G) is used as a
shield. The matrix card guard is used as the shield because
its PC board trace physically surrounds the high (H) and
low (L) traces.
same potential as signal high, protection from possible
hazardous voltages (up to 2ooV) must be provided. Many
instruments have the capability of configuring their input
or output such that a driven guard is placed on the inner
shield of a triax connector. The outer shield, connected to
system common, provides protection from the guard
voltage. When making connections from the matrix card
to the DUT, make sure that a safety shield is used as shown
in the illustration.
2.4.2 Differential
2.4.4 Sensing
Switching
The differential
or floating switching
configuration
is
shown in Figure 2-5. The advantage of using this configuration is that the terminals of the source or measure instrument are not confined to the same matrix crosspoint. Each
terminal of the instrument can be connected to any of the
96 matrix crosspoints. Again, the guard terminals of the
matrix card are used as a shield.
2.4.3 Guarding
Figure 2-6 shows how the matrix card can be used with
a driven guard. Since the driven guard is at virtually the
Figure 2-7 shows how the matrix card can be configured
to use instruments that have sensing capability. The main
advantage of using sensing is to cancel the effects of matrix
card path resistance (< 1.5II) and the resistance of external cabling. Whenever path resistance is a consideration,
sensing should be used. In the illustration,
matrix card
guard is again used as a shield. In a system whew a driven
guard is required, matrix card guard (G) can be disconnected from circuit LO and connected to the guard potential. However, make sure that the guard is adequately insulated to prevent possible electrical shock, or use quadrax
cables using the outer shield as a grounded safety shield.
Shield
Figure 2-4. Single-Ended
2-6
Switching
Example (Guard Used as Shield)
OPERATION
Figure 2-5. Differential
Switching
Example (Shielded)
1
Columns
SdElY
Shield
Figure 2-5. Driven Guard Example (Shielded)
2-7
OPERATION
7071
System Common
Figure 2-7. Sensing Example (Shielded)
2.5 CONNECTION
METHODS
makes it most convenient to connect the matrix card to a
test fixture that uses a “rack and panel” receptacle.
As shipped, all rows and columns of the 8 x 12 matrix
are connected to the two “rack and panel” receptacles
mounted on the rear panel of the matrix card. These rweptacles will mate with either the optional mass terminated
cable (Model 7078~MTC) or the plug provided in the optional connector kit (Model m-KIT).
If the receptacles
are not going to be used, they should be disconnected from
the matrix. Connections are then made directly to quickdisconnect terminal blocks.
The following paragraphs explain the three connection
methods. Keep in mind that based on convienence and
performance considerations, it may best to use a combination of connection methods. For example, it may be most
convienent to connect instrumentation
to the matrix using quick-disconnect
terminal blocks, while connecting
DUT to the matrix using a mass terminated cable.
Some advantages of each of the connection
as follows:
methods are
Mass Terminated Cable Method (Model 7U7&MTC)Probably the most convenient method to make conn&ons
to the m&ix card. By cutting the cable in half (or wherever
appropriate), two separate cables, unterminated
at one
end, will result. These cables can then be hard wired to
DUTs or to a user’s test fixture. The plug on each cable
will then connect to the ROWS or COLUMNS receptacle
on the card. Using the whole cable (both plugs intact)
2-8
Direct Connection Method--This
method makes connections at the quick-disccmn&
terminal blocks bypassing the
“rack and panel” receptacles. This method should be used
when optimum guarding and/or shielding (i.e. high frequency noise) are required. If using the Model 7Cl78-MTC
cable, the concentric guard or shield conductor will be terminated at the receptacle. The direct connection method
allows concentric guard and shield conductors to be extended to the terminal blocks. Another advantage of this
method is that it is convenient to connect unterminated
cables from instrumentation
to the terminal blocks.
Connector Kit (Model 717%KITFThis
kit contains a plug
that mates to the “rack and panel” receptacles. This plug
is used to custom build a cable assembly that meets the
user’s requirements. This allows the user to s&d the cable
and wire only the rows and column needed for a particular
application. Thii can result in a cable assembly that is
much smaller in diameter than the Model 7078MCT.
Each conductor of the 20-foot Model 7UiB-ME-20 cable
has 4Nrn0 of resistance. Each conductor of the 5-foot
Model [email protected] cable has l2Om0 of resistance. In an
application where path resistance is critical, this path
resistance may be too high. Thus, another advantage of
the connector kit is to build shorter, low resistance cables.
An alternative to building a cable from scratch is to cut the
Model ?378-M’IC cable at a length that is suitable and then
attach the plug to it.
OPERATION
WARNING
To avoid electrical shock which could result in
iniurv or death. make sure all Dower is off and
&r&d energy in external ciffi&try Is dischaged before making any connections to the matrix
card.
CAUTION
Contamination will degrade the Performance of
tha matrix card. To avold contamination, always
grasp the card by the handle and side edges.
Do not touch the edge connectors of the card,
and do not touch the board surfaces or components. On “rack and panel” connectors and
quick disconnect termlnal blocks, do not touch
areas adjacent to the electrical contacts.
2.5.1 Connections
Terminated
Modified
Using Mass
Cable (Model 70784TC)
The Model 7W78-MTC is a 36 conductor cable terminated
with a “rack and panel” plug on each end. This cable is
used to connect the “COLUMNS”
or “ROWS” receptacle
on the rear panel of the card to external instrumentation
and test circuits. Figure 2-8 shows how two cables can be
used to connect rows and columns of the matrix card to
external “rack and panel” receptacles. The external recep
Lades can then be hard wired to other connectors or wired
directly to instrumentation
and DUTs.
Use the following procedure to connect the Model 7078
M’K cable to the matrix card:
1. Install the matrix card in the Model 707 mainfrane as
explained in paragraph 2.3.
2. Place the plug of the cable on the appropriate “rack and
panel” receptacle such that the large diameter keying
pin of the plug aligns with the large keyway of the recep
tade (see Figure 2-9).
3. Using a slotted screwdriver, turn the locking screw
clockwise until the plug is fully mated to the receptacle.
The same basic procedure applies for connecting
cable plug to an external receptacle.
1. Remove 118” of insulation from the wires that are to be
connected to the receptacle.
2. Using the Model 7U7SHcT crimping tool, connect a wire
cnmp tail to each of the wires.
3. Figure Z-10 provides contact identification
for “ROWS”
and “COLUMNS”
receptacles. Using this ilh~stration as
a guide, insert the wire crimp tails into the receptacle.
use the Model Xi78 CIT insertion tool to push each wire
crimp tail completely into the receptacle.
the
Mass Terminated
Cable
Another way to use the Model 7UiSMTC cable is to remove
one of the plugs. Cutting the cable in half will provide hvo
10 foot cables. Each cable can then be mated to the “ROWS”
or “COLUMNS”
receptacle (see Figure 2-11). The wire end
of each cable can then be wired to another connector or
wired directly to instrumentation
or DUTs. The cable contains twelve bundles of wires each of which corresponds
to a row or column. Each bundle contains three wires; a
bare wire (guard) and hvo insulated wires that have a unique color combination for identification
purposes. Table
2-3 provides the color combinations for each bundle. For
example, with the cable connected to the “ROWS” receptacle of the matrix card, Row E can be identified by locating
the bundle that has a red insulated wire (H) and a blue
insulated wire (L). The bare wire in the bundle is guard
G).
NOTE
If another “rack and panel” plug is to be attached to the unterminated end of the cable, refer to
the connection procedure in paragraph 2.5.3.
The outer side of the foil shield is inslulated while the inner wrapping is conductive (guard). When the cable is cut,
it is likely that the conductive side of the bundle wrapping will become exposed. Thus, each bundle, as well as
each bare wire, should be insulated as follows:
1. Place a length of Teflona tubing over each bare wire.
2. Place a length of shrink tubing over the bundle such
that the frayed end of the bundle wrapping and part
of the [email protected] tubing is covered.
3. Heat the shrink tubing.
Receptade wuing
“Rack and panel” receptacles (Model 7UiSMTR) along with
recommended installation tools are available from Keithley
(see Table 2-2). Perform the following steps to wire a “rack
and panel” receptacle.
2-9
OPERATION
Table 2-2. Model 7071 Available Accessories
Model
or Part
Description
Model 7078~CIT: Insertion
and Extraction
Model 7UiB-HCT: Hand Crimping
Model 7U78-KIT: Connection
Model 7U78NTR:
Connector
CS-570-3: Quick Disconnect
Contains one “rack and panel”
wire crimp tails.
Kit (Plug)
and 40
1.5 meter (5 ft.), 36 conductor cable terminated with
“rack and panel” plugs. Mates to “rack and panel”
receptacles.
Cable
Same as the Model 7078~MlYZ-5 except that it is 6
meters (20 ft.) in length.
Kit (Receptacle)
Contains one “rack and panel” receptacle, 40 wire
crimp tails, and mounting hardware.
Terminal
3-terminal block accomodates up to 16 AWG wires.
Mates to matrix card board pin terminals.
Block
I
2-10
plug, housing
Cable
Mass Terminated
“rack
Used to connect wire crimp tails to W18to U26 gage
wire.
Tool
Model 7078~M’IC-5: Mass Terminated
Model 7(ns-m-20:
Used to install/remove wire crimp tails into/from
and panel” plugs and receptacles.
Tools
OPERATION
Rack and Panel Receptacles
(see Table 2-2 for Model number)
Figure 2-8. Connections
Uslng two Model 7078~MTC Cables
2-11
Table 2-3. Model 7078~MTC Wire Identification
lH =
L=
G =
High
Low
Guard
Receptacle
,
Figure 2-9. Connecting
242
Plug to Receptacle
OPERATION
Figure 2-10. Receptacle
Contact Assignments
2-B
OPERATION
Model 7078.MTC
Cable (Cut in half)
Figure 2-11. Connections
2-14
Using One Model 7078.MTC Cable Cut in Half
OPERATION
2.5.2 Direct Connections
With this method, connections are made directly to quickdisconnect terminal blocks. The “rack and panel” receptacles are not used. Additional terminal blocks are available
from Keithley (see Table Z-2).
NOTE
For optimum performance, use a low noise, shielded cable that has excellent insulation qualitites
such as [email protected] or polystyrene).
w
Perform the following
steps to wire the matrix
Triaxial Cable
card:
1. Perform one of the following procedures (A or B):
A. If leaving the terminal blocks connected to the receptacles, carefully pull the appropriate blocks off the
matrix PC board. lie wrap or tape the loose
assemblies together and position them out of the
Way.
B. If using the supplied terminal blocks, disconnect the
receptacle wires from the ones you are going to use
and carefully pull them off the PC board. lie wrap
or tape the loose receptacle wires together and position them out of the way.
Figure 2-12. Termlnal Block Connections
2.5.3 Connections
Using Connector
(Model 7078-KIT)
Kit
The Model 7U78XlT contains the parts of one “rack and
panel” plug. This kit allows the user to build a cable that
will mate to the “rack and panel” receptacles of the matrix
card.
NOTE
Receptacle wires are tagged for identification.
Red
wires are HI terminals, black wires are LO, and
white wires are GUARD. Contact identification
at
the receptacles is provided in Figure 2-10.
2. Using a screwdriver, connect the circuitry
to the terminal
blocks. Figure 2-12 shows how a triaxial cable may be
connected. The screw terminals accept up to $16 AWG
wire.
3. The terminal blocks should be connected to the matrix
cm? during installation of the card into the mainframe.
The procedure to do this is contained in paragraph 2.3.
NOTE
The following procedure shows how to properly
connect a 36 conductor cable to a “rack and panel”
plug. The cable used in the procedure is the same
one used in the Model iQ78-MTC and is available
from Belden (P/N 9734). Modify the procedure accordingly if using a different cable or individual
wires and use Figure 2-23 instead of Figure 2-14.
Perform the following steps to connect the 36 conductor
Belden cable to the Model 7W78XIT plug:
Feed one end of the cable through the plug housing. Slide the housing far enough down the cable to
set it out of the way.
2-15
OPERATION
the locking screw of the plug with shrink tubing as shown in Figure Z-15.
8. Orient the cable to the plug as shown in Figure 2-15,
and using Figure 2-14 as a guide, insert the wire crimp
tails into the plug. Use the Model 7078 UT insertion
tool to push each wire crimp tail completely into the
plug.
9. Slide the housing over plug and install the four screws
that secure the housing to the plug.
10. Tighten the hvo cable clamp screws on the housing.
Z Insulate
NOTE
Refer to Figure 2-W for steps 2 through
5.
2. Using a sharp knife, remove 1%” of insulation fmm the
end of the cable. Be careful not to cut into the insulated
shield of any of the internal wire bundles.
3. Remove one inch of insulated shielding from each of
the 12 bundles of wires.
4. Insulate the bare guard wire of each bundle so that they
do not short out to each other. The insulation must be
able to withstand a 2OLW potential.
5. Remove 118” of insulation from the 24 insulated wires.
6. Using the Model 7U78-HCI crimping tool, connect a
wire crimp tail to each of the 36 wires. The wires are
24 gage so be sure to use the slot labeled “22-26” on
the tool.
The “rack and panel” plug will mate to either receptacle
on the matrix card in the same manner as the Model 7078
M’IC cable. The other end of the cable can be wired directly
to instrumentation
or DUTs, or to another connector.
NOTE
Figure 2-14 shows where the wires of each bundle
belong. The wires in each bundle have a unique
color combination that is different from the color
combination of any other bundle.
Belden 9734 Cable
Figure 2-13. Cable Preparation
2-16
OPERATION
Larg;Xameter
Keying
Plug (Viewed from Cable side)
Figure 2-14. Connecting
Large Diameter
Beldon 9734 Cable to Plug
Keying Pin
elden 9734 Cable
Figure 2-15. Cable Positions
2-v
OPERATION
2.6 MATRIX EXPANSION
With the use of additional Model 7071 matrix cards, larger
matricies can be configured and are described in the
following paragraphs.
Model 7071 matrix cards installed in slots 1, 2 and 3 of the
Model 7CV can be electricaIly isolated from slots 4, 5 and
6 by removing the backplane row jumpers. With the
jumpers removed, the Model 7U7can accomodate two complete, separate matrices using Model 7071 matrix cards (see
Figure 2-V).
NOTE
Table 2-4. Narrow Matrix Expansion’
Some configurations
require that the backplane
row iumpers of the Model 707 be removed. The
pro&d&
to remove these jumpers can be found
in the Model 707 Instruction Manual.
2.6.1 Narrow
Matrix
Installed
Matrix Cards
Expansion
Resulting
1 Card
Cards
2
3
4
5
6
As shipped from the factory, the rows of all six slots of the
Model 707 are internally connected together. Thus, each
card installed in the mainframe extends the matrix by 12
columns. For example, three cards installed in the Model
7U7will result in an 8 x 36 matrix. Figure 2-16 shows three
matrix cards installed in slots 1, 2 and 6.
8xl2
8 x
8 x
8x48
8 x
8 x
Cards
Cards
Cards
Cards
Matrix
24
36
60
72
‘Backplane row jumpers between slots 3 and 4 of mainframe must be installed for a matrix larger than 36
columns.
----I
7071
7071
7071
(Slot 1)
(Slot 2)
(slot 6)
ROWS
H-
Figure 2-16. Narmw Matrix Example (6 x 36) (Backplane
2-18
Jumpers Not Removed)
OPERATION
I
Backplane
Jumpers
Removed
Figure 2-17. Two 8 x 36 Matrices Using Six Model 7071s
2.6.2 Wide Matrix
Expansion
Table 2-5. Wide Matrix Expansion’
With the backplane row jumpers of the Model 707 removed, a wide matrix (16 rows) can be configured as shown
in Figure Z-18. Columns of two cards can be connected
together by using the Model 7071 M’IC cable or by using
individual wires from the “COLUMN”
terminal blocks of
one card to the “COLUMN”
terminal blocks of another.
Column connections to DUTs can be made at the “COG
UMN” terminal blocks or at a “COLUMNS”
receptacle (if
not already used) using methods described in paragraph
2.5. Each screw terminal of the terminal blocks will accomodate an additional 822 AWG wire.
Table 2-5 summarizes
Model 707 mainframe.
the wide mati
possibilities
‘Model
707 backplane
row jumpers removed
per
2-19
OPERATION
I
A-Rows -H---
7071
I--
(Slot 1)
Internal Backplane
Jumpers Removed
1
A-
I
1
Figure 2-18. Wide Matrix Example (16 x 24)
2.6.3 Partial
Matrix
Implementation
A fully implemented matrix provides a relay at each potential aosspoint. For example, a fully implemented 16 x 24
matrix utilizing four Model 7Dil matrix cards contains 384
cmsspoints. A partially implemented matrix can be obtained by removing one Model 7071 from the mainframe (see
Figure 2-19). The partial mati
is still 16 x 24, but contains only 288 cmsspoints. An obvious advantage of a partial matrix is that fewer matrix cards are needed. Another
reason to use a partial matrix is to keep certain devices from
being connected directly to other certain devices. For example, a source in Figure 2-19 cannot be connected to DIJT
X2 with one “accidental” crosspoint closure. Three specific
cmsspoints must be closed in order to connect a source
to DUT X2.
Methods to connect columns together and to external circuitry are explained in the previous paragraph.
2-20
2.6.4 Mainframe
Matrix
Expansion
Matrices using up to 30 Model 7071 mahix cards are possible by daisy-chaining five Model 7U7mainfhmes
together.
Using 30 Model 707l matrix cards provides
2880
crosspoints.
In general, connecting columns of a card in one mainframe
to the columns of a card in another mainframe increases
the the mw numbers of the matrix. Connecting TOWSof
any card in one mainframe to the rows of any other card
in a second mainframe increases the column numbers of
the matrix. See the Model 707 Instruction
Manual for
detailed
information
on daisy-chaining
Model 707
mainframes.
OPERATION
-Columns
Externally
connected together
Internal
Backplane
Jumpers
Removed
Figure 2-19. Partial Matrix Expansion
2.7 TYPICAL
CONNECTION
SCHEMES
The information in this paragraph provides some typical
connection schemes for single card, multiple card and
multiple mainframe system configurations.
All of the
following examples show Model 7078~MTC cables cut in
half. Keep in mind however, that in systeiw where path
resistance is critical, cables should be kept as short as
possible.
2.7.1 Single
(16 x 24)
Card System
Figure 2-20 shows how external connections for a single
card system might by made. Instrumentation
is connected
to matrix card Tows. Using standard instrument cables that
are unterminated at one end make it convenient to make
connections at the quick-disconnect terminal blocks of the
matrix card. Instrumention
uses only four rows allowing
the rest of the rows to be used by DUTs. A Model 7UZWfK
cable cut in half, is then used to connect DUTs to matrix
card columns and the remaining rows.
2-21
OPERATION
Figure 2-20. Single Card System Example
2.7.2 Multiple
Card System
Figure 2-21 shows a system using four matrix cards. Again,
instrumentation
is connected to matrix card rows via the
quick-disconnect terminal blocks. However, these connections could have been made using a Model 707&MTC cable
if desired. DUTs are connected to columns using two
Model 70%Mx:
cables cut in half.
2-22
2.7.3 Multiple
Mainframe
System
Figure 2-22 shows a system using eight matrix cards, requiring two Model 7TJ7sdaisy-chained together. In this configuration all instrumentation
and DUTs are connected to
matrix card columns using four Model 707SMlC cables
cut in half. A single Model 707%MTC cable is used to connect the TOWSof the master mainframe to the rows of the
slave mainframe. Note that if path resistance is a critical
factor, use a cable that is as short as possible. A Model
7U7SMK cable can be shortened or a custom cable can
be built using two Model 7U7tXlT connector kits.
OPERATION
0
I
0
0
I
Figure 2-21. Multiple Card System Example
2-23
OPERATION
Figure 2-22. Multiple Mainframe Example
2-24
OPERATION
Figure 2-23. Plug Contact Assignments
2.25/z-26
SECTION 3
Applications
3.1 INTRODUCTION
General applications to test thick film resistor networks
and transistors are provided in this section. These applications are intended to demonstrate the versatility of using
the matrix card in test systems.
3.2 THICK FILM RESISTOR
TESTING
NETWORK
A dedicated matrix system for testing thick film resistor
networks is shown in Figure 3-l. This particular system
provides three different methods to check thick films; fourwire resistance measurements, voltage measurements
using an applied voltage, and voltage measurements using
an applied current. In general, the method to use for
testing is dictated by the intended application of the resistor
network and the values of the resistors.
The system shown in Figure 3-l tests three 3-element thick
films, but can be expanded to test more by simply using
additional Model 7071 matrix cards. The Model 707 will
accomodate six matrix cards. Daisy-chaining
five Model
70% expands the system to 30 matrix cards allowing 90
three-element thick films to be tested.
Thick Film Resistor Networks
4.terminal R
Model 196
Model 7071 Matrix Card
Model 226
Figure 3-l. Thick Film Resistor Network Testing
3-l
APPLICATIONS
3.2.1 Four-terminal
Ohms Measurements
1) and B3 are closed to measure the combined
of Rl and R2.
For general purpose testing, the Keithley Model 196 can
be used to make Pterminal resistance measurements of
each thick film. As shown in Figure 3-2, OHMS HI and
OHMS SENSE HI are connected to one matrix row, and
OHMS LO and OHMS SENSE L4l are connected to
another matrix row. The third pole (G) of the matrix is not
shown since it is not used. With this configuration,
the
resistance of each resistor element and/or combined
elements can be measured by closing the appropriate
crosspoints. In Figure 3-2, crosspoints Al (row A, column
The effects of thermal EMFs generated by relay contacts
and connections can be cancelled by using the offset compensated ohms feature of the Model 196. To compensate
for thermal EMFs, close two crosspoints (such as Al and
Bl) that will short the input of the Model 196, enable ZERO
to cancel internal offset, and then enable offset compensated ohms.
Thick Film
Model
196
I
Model 7071 (Two poles used)
196
EquivalentCircuit
Figure 3-2. 4.Terminal Ohms Measurements
3-2
resistance
APPLICATIONS
3.2.2 Voltage
Divider
Checks
For thick film resistor networks that are going to be used
as voltage dividers, it may be desirable to test them using
voltages that simulate actual operating conditions. This is
a particularly useful test for resistor networks that have
a voltage coefficient specification. The test system in Figwz
3-1 uses a Keithley Model 230 to source voltage and the
Model 196 to measure voltage.
A consideration in these checks is the affect of the Model
196 input impedance on voltage measurements. The input impedance is shunted across the resistor being
measured. The resultant divider resistance is the parallel
combination of the resistor under test and the input impedance. As long as the input impedance is much larger
than the resistor being tested, the error introduced into
the measurement will be minimal. Minimum input impedance requirements are, of course, determined by the
accuracy needed in the measurement. The input impedances of the Model 196 are as follows: 3OOmV and 3V
ranges, >lGfl; 30V range, UMQ; 300V range, lO.lMfl. For
better input impedance requirements, the Keithley Model
617 Electrometer can be incorporated
to measure voltage.
into the test system
Another factor to be considered when checking low voltage
dividers is thermal EMFs generated by the matrix card. A
m&ix card crosspoint can generate up to i5cV of thermal FMF. Thus, when making low voltage measurements
be sure to account for this additional error,
Even though four-terminal
connections are made at the
Model 196 and the resistor networks, the sense leads are
internally disconnected from the input of the DMh4 when
the volts function is selected. The simplified test system
is shown in Figure 3-3.
The thick fii
is tested by applying a voltage across the
resistor network and measuring the voltage across each
resistor element and/or across combined elements. In
Figure 3-3, crosspoints Cl and D4 we closed to apply
voltage across the network, and crosspoints A3 and B4 are
closed to measure the voltage drop across R3.
3-3
APPLICATIONS
Thick Film
‘7
“2
LH
LH
I
I
_H
m
-
“3
-L
LH
4-
Model 7071 (Two poles used)
Model
230
Rl
Rz
R3
230
Equivalent Circuit
Figure 3-3. Voltage Divider Checks
3-4
APPLICATIONS
3.2.3 Current
Shunt
Checks
As with voltage dividers, it may be desirable to test current shunt resistor networks under simulated operating
conditions. The test system in Figure 3-l uses a Keithley
Model 228 to source -nt
through the thick film resistor
network and the Model 196 to measure voltage. As
previously mentioned, the sense leads of the Model 196
are internally disconnected from its input in the volts function resulting with the simplfied test circuit shown in
Figure 34.
CAUTION
To prevent damage not covered by the warranty, never soutce more than 1A to the matrix card
and never switch more than 0.5A. To safely
souse more than 0.5A (but less than IA), first
set the current source to output zero and then
close and/or open the appropriate crosspoints.
This is called “cold” switching.
The thick film is tested by sourcing a current through the
current shunt network and measuring the voltage drop
across each resistor element and/or across combined
resistor elements. In Figure 3-4, crosspoints El and F4 are
closed to source current through the shunt, and crosspoints Al and 82 are closed to measure the voltage drop
across Rl.
3.3 TRANSISTOR
TESTING
A matrix system for testing DC parameters of transistors
is shown in Figure 3-5. This system uses a current source
(Keithley Model 224), a voltage source (Keithley Model 230)
and a DMM (Keithley Model 196) to measure current
and/or voltage. This system tests three transistors, but can
be expanded to test more by simply using additional Model
7Uil matrix cards. The Model 707 will accomodate six
matrix cards. Daisy-chaining five Model 707s expands the
system to 30 matrix cards allowing 90 transistors to be
tested.
NOTE
To check FE%, or transistors that have high gain
or low power, equipment that has lower offset CUTrent and higher impedance must be used. To check
these devices, the Keithley Model 7072 Semiconductor Matrix Card and the Keithley Model 617
Electrometer can be used.
3-5
APPLICATIONS
Thick Film
r
Model
Source
228
Model 7071 (Two poles used)
I
H
22s
Equivalent
Circuit
Figure 3-4. Current Shunt Checks
3-6
APPLICATIONS
L--------------------“A
Model 7071 Matrix
Model
Card
224
Figure 3-5. Transistor Testing
3.3.1 Current
Gain Checks
The DC current gain of a general purpose transistor can
be checked by configuring
the transistor as a commonemitter amplifier. Figure 3-6 shows which crosspoints to
dose to configure the amplifier circuit. In this circuit, gain
is cz.!cuIated by dividing collector -nt
(measured by the
Model 196) by base current (sourced by the Model 224).
A proflle of the transistor operating characteristics can be
obtained by measuring
the collector current over a
specified voltage range (V,) for different base bias CUTrents. For example, Figure 3-7 shows the characteristics of
a typical NPN silicon transistor at base bias currents (IB)
of 204, 40$x, 6Ofi and gOj~4.
3.3.2 I, and V,, Measurements
The versitility of using a matrix is demonstrated in Figures
3-8 and 3-9. The transistor is still configured as a commonemitter amplifier, but the Model 196 is removed from the
collector circuit and used to measure emitter current and
base-to-emitter voltage. Notice that external connection
changes are not required. All connection changes are accomplished by control of matrix crosspoints.
3-7
APPLICATIONS
196
/[email protected]
IE
.L
Gain = *
r-h
Equivalent
Circuit
Measure
VWl
Model
230
Model
224
-
I
’
Model 7071 (Two poles used)
Figure 3-6. Transistor Current Gain Checks
3-8
APPLICATIONS
‘Oi
* .... . ........
/
i
......’ j
I I L-l--H:
I
0
1
I
ve
Figure 3-7. Common-Emitter
::.i/ i I
I
;
3
4
t
2
/.+BO
p
5
, vans
Characteristics
of an NPN Silicon Transistor
3-9
APPLICATIONS
SOWX
V
Model
230
Model
224
Figure 3-8. lhnsistor
3-10
I, Measurements
APPLICATIONS
224
Vorl
I
Amps LO
HD
$~f
I -
Output
I
Common
, .
‘H F
IL.
I
I1
I
I
II
I1
II
Source
V
Model
230
Model
224
I
Model 7071 (Two poles used)
Source
I
Figure 3-9. Transistor
VBE Measurements
3-11
SECTION 4
Service Information
4.1 INTRODUCTION
This section contains information necessary to service the
Model 7071 General Purpose Matrix Card and is arranged
as follows:
4.2
Handling
and Cleaning Precautions:
Discusses
handling procedures and cleaning methods for the
matrix card.
4.3
Relay Test Program: Explains how to connect the
matrix card to the Model 707 mainframe for the relay
test program.
4.4
Performance Verification:
necessary to determine
properly.
of Operation:
nectars. Do not touch areas adjacent to electrical contacts. When servicing the card, wear clean, white cotton gloves.
If making solder repairs on the circuit board, use a flux
that is rosin RMA based. Remove the flux from these
areas when the repair is complete. Use [email protected] TMS
or TE, or the equivalent along with plenty of clean cotton swabs to remove the flux. Take care not to spread
the flux to other areas of the &it
board. Once the flux
has been removed, swab only the repaired area with
methanol, then blow dry the board with dry nitrogen
gas.
After cleaning, the card should be placed in a 50°C low
humidity environment for several hours.
Covers the procedures
if the card is operating
4.3 RELAY TEST PROGRAM
4.5
Principles
operation.
Briefly
discusses circuit
4.6
Special Handling
of Static-Sensitive
Devices:
Reviews precautions necessary when handling staticsensitive devices.
4.7
Troubleshooting:
Presents some troubleshooting
tips for the matrix card.
4.2 HANDLING AND CLEANING
PRECAUTIONS
Because of the high impedance circuits on the Model 7071,
care should be taken when handling or servicing the card
to prevent possible contamination,
which could degrade
performance. The following precautions should be taken
when handling the matrix card.
1. Do not store or operate the card in an environment
where dust could settle on the circuit board. Use dry
nitrogen gas to clean dust off the card if necessary.
2. Handle the card only by the handle and side edges. Do
not touch any board surfaces, components, or edge con-
SETUP
The Model 707 comes equipped with a test program on
disk that will test all relays of Model 7071s installed in the
mainframe. The test program will flag any relay that fails
to close when energized or open when de-energized. lnstructions for using the test program with an IBM PC or
XT, or HP 200 or 300 series computer are contained in the
Model 737 Instruction Manual.
Perform the following
for relay testing:
steps to configure
the Model 7071
1. Remove the relay test terminal block from the rear panel
of the Model 707. This is a quick-disconnect
terminal
block and simply pulls off the rear panel terminal ship.
2. Connect the relay test terminal block to rows A and B
of any Model 7071 card installed in the mainframe as
shown in Figure 4-l. Note that terminals 5 and 6 of the
relay test terminal block must be shorted together. Terminals H, Land G of row B of the Model 7U7l must also
be shorted together.
3. Re-install the relay test terminal block into the rear panel
of the Model 707 mainframe and refer to the Model 707
Instruction Manual to run the test program.
4-l
SERVICE INFORMATION
123456
Relay Test Terminal
Row A
Figure
4.4 PERFORMANCE
VERIFICATION
The procedures in this section are rather lengthy due to
the large number of row and column combinations that
are checked. As an alternative to this extensive testing, it
may be desirable to check only those paths that are going
to be used, or those that are suspected of being faulty.
The procedures in this section make external equipment
connections at the terminal ship on the PC board. If using
the “rack and panel” receptacles of the m&ix card to make
connections, modify the procedures accordingly. Connection techniques to “rack and panel” receptacles are covered
in Section 2.
4-2
verification
procedures
I
I
4-1. Relay Test Setup
The following paragraphs dlscoss performance verification
procedures for the Model 7071, including path resistance,
offset current, contact potential, and isolation.
The perfomumce
Row B
must be per-
formed with only one matrix card (the one being checked)
installed in the Model 7W mainframe. Also, the Model 707
must not be daisy-chained to another Model 707.
CAUTION
Contamination will degrade the performance of
the matrix card. To avoid contamination, always
grasp the card by the handle and side edges.
Do not touch the edge connectors of the card,
and do not touch the board surfaces or components. On “rack and panel” connectors and
quick disconnect terminal blocks, do not touch
areas adjacent to the electrical contacts.
NOTE
Failure of any performance verification test
indicate that the matrix card is contaminated.
paragraph 4.2 to clean the card. If the test still
after cleaning, then try cleaning the backplane
the Model 7U7 Instruction Manual).
may
See
fails
(see
SERVICEINFORMATION
4.4.1 Environmental
Conditions
All verification measurements should be made at an ambient temperature between 18’ and 28”C, and at a relative
humidity of less than 70%.
4.4.2 Recommended
Equipment
Table 41 summarizes the equipment necessary for performance verification,
along with the application for each
unit.
NOTE
Do not use the Model 7U70Universal Adapter Card
as an extender card to verify performance of the
Model 7071. The Model 7071 must be installed in
the Model 707 mai”frame.
4.4.3 Path Resistance
Tests
Perform the following steps to verify that each contact of
every relay is closing properly and that the resistance is
within specification.
NOTE
Refer to Figure 42 for the following
procedure.
1. Turn the Model 7U7 off if it is on.
2. Using bare jumper wires, connect all terminals of the
matrix columns together to form one common terminal. Each screw terminal of the quick-disconnect terminal blocks will accomodate two #22 AWG wires.
Keep the jumper wires as short as possible.
3. Remove the eight “ROWS” quick-disconnect terminal
blocks from the PC board of the matrix card. This
allows test lead coruwctions to be made at the PC board
tennina posts.
4. Place the Model 7071 in slot 1 of the Model 707. but
do not push it all the way into the mainframe.
5. Set the Model 196 to the 3OLXlrange and connect four
test leads to the OHMS and OHMS SENSE input.
6. Short the four test leads together and zero the Model
196. Leave zero enabled for the entire test.
7. Connect OHMS HI and OHMS SENSE HI of the
Model 196 to the common terminal (jumper). It is
recommended that the physical connections be made
at columns 1 and I2 as shown in Figure 42.
8. Connect OHMS LO and OHMS SWSE LO to the high
(H) terminal post of ROW A.
9. Feed the test leads through the cable clamp of the
matrix card and push the card all the way into the
mainframe. Xghten the two spring loaded screws to
completely mate the card with the backplane.
10. Turn on the Model 707 and program it to close crosspoint Al (ROW A, COLUMN l), and verify that the
resistance of this path is <1.5R.
11. Open crosspoint Al, and close A2. Verify that the
resistance of this path is <1.5R.
12. Open crosspoint AZ, and close A3. Verify that the
resistance of this path is ~1.53.
13. Using the basic procedure of steps 10 through 12, check
the resistance of ROW A high (H) terminal paths for
COLUMNS 4 through I2 (crosspoints A4 through AU).
14. Turn the Model 707 off and pull the matrix card out
of the mainframe approximately 6” in order to gain access to the terminals.
15. Move the OHMS LO and OHMS SENSE LO test leads
to the low (L) terminal of ROW A.
16. Repeat steps 9 through I2 to check the low (L) tetial
paths of ROW A.
17. Turn the Model 707 off and move the OHMS Lo and
OHMS SENSE Lo test leads to the guard(G) tetial
of ROW A.
l8. Repeat steps 10 through 12 to check the guard (G) terminal paths of ROW A.
19. Repeat the basic procedure in steps 1 through 18 for
ROWS B through H.
43
SERVICE INFORMATION
Table 4-1. Verification
Description
Equipment
1 Model
I
Keithley
196
3ooo; 0.01%
Path resistance
Keithley
617
lOpA, lOOpA; 1.6%
1OOVsource; 0.2%
Offset current isolation
Keithley
181
2mV; 0.015%
Contact potential
Triax cable
(unterminated)
Keithley
RI25
-
Offset current
Low thermal cable
(unterminated)
Keithley
1484
-
Contact potential
Electrometer
source
w/voltage
Specifications
Application
I
I
L---------------------Model
Figure 4-2. Path Resistance
44
7071
Testing
isolation
SERVICEINFORMATION
4.4.4 Offset Current
Tests
These tests check leakage current between high (H) and
low (L) (differential offset current ) and from high and low
to guard (G) (common mode offset current) of each
pathway. In general, these tests are performed by simply
measuring the leakage current with an electrometer. In the
following procedure, the Model 617 is used to measure
leakage current.
Perform the following
procedure
to check offset current:
1. Turn the Model 707 off if it is on.
2. Connect the Model 617 to a quick-disconnect
terminal
block as shown in Figure 4-3. Do not connect the terminal block to the matrix card at this time.
3. Place the m&ix card in slot 1 of the Model 707, but
do not slide it all the way into the mainframe.
4. On the Model 617, select the 2oOpA range, and enable
zero check and zero correct in that order. Leave zero
correct enabled for the entire procedure.
5. Connect the pre-wired terminal block to ROW A of the
matrix card.
6. Feed the test leads through the cable clamp of the
matrix card and push the card all the way into the
mainframe. Tighten the two spring loaded screws to
completely mate the card with the backplane.
7. Turn on the Model 707
8. Program the Model 707 to close crosspoint Al.
9. On the Model 6V, disable zero check and verify that
it is <lOOpA. This measmwnent is the leakage current
of the pathway.
10. On the Model 6V, enable zero check and on the Model
707, open crosspoint Al.
11. Repeat the basic procedure in steps 8 through 10 to
check the rest of the pathways (crosspoints A2 through
AU) of the row.
12. Turn off the Model 707 and slide out the matrix card
far enough to gain access to the pre-wired terminal
block.
13. Move the terminal block down to ROW B and repeat
the basic procedure in steps 6 through 11 to check
crosspoints Bl through BU.
14. Repeat the basic procedure in steps 12 and l3 for the
remaining rows (ROWS C through H).
15. Turn off the Model 707, and slide the matrix card out
far enough to gain access to the pre-wired terminal
block.
16. Rewire the terminal block as shown in Figure 4-4.
17. Repeat steps 5 through 14 to check common mode offset current.
4-5
SERVICE INFORMATION
I- -----~~~~~--_------__
Model
Figure 4-3. Differential
4-6
7071
Oftset Current Testing
SERVICE INFORMATION
r
L
1
.---------------------
_I
Model 7071
Figure 4-4. Common Mode Offset Current Testing
4.4.5 Contact
Potential
Tests
These tests check the EMF generated by each relay contact pair (H and L) for each pathway. The tests simply consist of using a nanovoltmeter (Model l81) to measure the
contact potential.
Perform the following
tial of each path:
procedure to check contact poten-
1. Turn the Model 707 off if it is on.
2. Set the Model 181 to the 2mV range, short the input
leads and press ZERO to null out internal offset. Leave
ZERO enabled for the entire procedure.
3. Connect the Model 181 to a quick-disconnect
terminal
block as shown in the illustration caption of Figure 45.
Do not connect the terminal block to the matrix card
at this time.
4. Place the matrix card in slot 1 of the Model 707. but
do not slide it all the way into the mainframe.
5. Connect the pre-wired terminal block to ROW A of the
matrix card.
6. Feed the test leads through the cable clamp of the
matrix card and push the card all the way into the
mainframe. lighten the two spring loaded screws to
completely mate the card with the backplane.
7. Turn on the Model 707
8. Program the Model 707 to close crosspoint Al.
9. Verify that the reading on the Model X31 is < 5~v. This
measurement is the contact potential of the pathway.
10. From the Model 707, open crosspoint Al.
11. Repeat the basic procedure in steps 8 through 10 to
check the rest of the pathways (crosspoints A2 through
Al2) of the row.
12. Turn off the Model 7CV and slide out the matrix card
far enough to gain access to the pre-wired terminal
block.
47
SERVICE INFORMATION
13. Move the terminal block down to ROW B and repeat
the basic procedure in steps 6 through 11 to check apsspoints 81 through BlZ.
14. Repeat the basic procedure in steps I2 and 1.3for the
remaining rows (ROWS C through H).
L-------------_-------~
Model
7071
-
Figure 4-5. Contact Potential Testing
48
SERVICEINFORMATION
4.4.6 Path Isolation
Tests
These tests check the leakage resistance (isolation) between
adjacent paths. A path is defined as the high(H), low(L),
guard (G) circuit from a row to a column that results by
closing a particular crosspoint. In general, the test is performed by applying a voltage (+lOOV) across two adjacent
paths and then measuring the leakage current accross the
paths. The isolation resistance is then calculated as R =
V/I. In the following procedure, the Model 617 functions
as both a voltage source and an ammeter. In the VII function, the Model 617 internally calculates the resistance from
the known voltage and current levels and displays the
resistive value.
NOTE
Refer to Figure 46 for the following
procedure.
1. Turn the Model 707 off if it is on.
2. Connect the Model 617 to two quick-disconnect
terminal blocks as shown in the illustration. Also, be sure
to install the three jumper wires as shown. Do not connect the terminal blocks to the matrix card at this time.
3. On the matrix card, unplug all ROW terminal blocks
from the PC board.
4. Place the matrix card in slot 1 of the Model 707, but
do not slide it all the way into the mainframe.
WARNING
The following steps use high voltage (1OOV).Be
sure to remove power horn the circuit before
making connection changes.
5. On the Model 617, select the 2pA range, and enable
zero check and zero correct in that order. Leave zero
correct enabled for the entire procedure.
6. Connect the two pre-wired terminal blocks to ROWS
A and B of the matrix card.
7. Feed the test leads through the cable clamp of the
matrix card and push the card all the way into the
mainframe. Tighten the two spring loaded screws to
completely mate the card with the backplane.
8. On the Model 6V, seleci the 2OpA range and release
zero check.
9. On the Model 617,press suppress to cancel offset current and then enable zero check.
10. On the Model 617, set the voltage source for +lC%‘, and
select the 20nA current range. Make sure the voltage
source is in standby.
11. Place the Model 617 in the VII measurement function
by pressing SHIFT OHMS.
12. Turn on the Model 707, and program it to close crosspoints Al (ROW A, COLUMN 1) and 82 (ROW B,
COLUMN 2).
13. On the Model 617, disable zero check and press
OPERATE to source 1OOY
14. After allowing the reading on the Model 617 to settle,
verify that it is >lOGQ. This measurement is the
leakage resistance (isolation) between ROW A, COLUMN 1 and ROW B, COLUMN 2.
15. Place the Model 6V in standby and enable zero check.
16. Turn off the Model 707. and slide the matrix card approximately six inches out of the mainframe to gain
access to the terminal blocks.
77. Move the two pre-wired terminal blocks down one row
so that they are located on ROW B and ROW C.
l&l. Reinstall the mahix card and turn on the Model 707.
19. Program the Model 707 to close crosspoints 82 and C3.
20. On the Model 617, disable zero check and press
OPERATE to source 1OOV.
21. After allowing the reading on the Model 617 to settle,
verify that it is >lOGR.
22. Using Table 42 as a guide, repeat the basic procedure
of steps 15 through 21 for the rest of the path pairs (test
numbers 3 through 11 in the table).
4-9
SERVICE
INFORMATION
Table 4-2. Path Isolation Tests
Test No.
:
i
5
6
7
8
l?l
11
Path Isolation
Test Equipment
Location
Row A, co1 1 to Row 8, co1 2
Row 8, co1 2 to Row C, co1 3
Row C, co1 3 to Row D, co1 4
Row D, co1 4 to Row E, co1 5
Row E, co1 5 to Row F, co1 6
Row F, co1 6 to Row G, co1 7
Row G, co1 7 to Row H, co1 8
Row G, co1 8 to Row H, co1 9
Row G, co1 9 to Row H, co1 10
Row G. co1 10 to Row H, co1 11
Row G, co1 11 to Row H, co1 12
Row
Row
Row
Row
Row
Row
Row
Row
Row
Row
Row
A and Row
B and Row
C and Row
D and Row
E and Row
F and Row
G and Row
G and Row
G and Row
G and Row
G and Row
Crosspoints Closed
B
C
D
E
F
G
H
H
H
H
H
L--------------------~~
Model
7071
Figure 4-6. Path Isolation Testing (Guarded)
4-10
Al and B2
82 and C3
C3 and D4
D4 and E5
E5 and F6
F6 and G7
G7 and H8
G8 and H9
G9 and H10
GlO and HZ1
Gil and HI2
SERVICEINFORMATION
4.4.7 Differential
Tests
and Common
Mode Isolation
These tests check the leakage resistance (isolation) between
high (H) and low(L) (differential), and from high and low
to guard (G) (common mode) of every row and column.
In general, the test is performed by applying a voltage
(low) across the terminals and then measuring the leakage
current. The isolation resistance is then calculated as R =
VII. In the following procedure, the Model 617 functions
as a voltage source and an ammeter. In the VII function,
the Model 6l7 internally calculates the resistance from the
known voltage and current levels and displays the
resistance value.
1. Turn the Model 707 off if it is on.
2. Connect the Model 617 to a quick-disconnect
terminal
block as shown in Figure 47. Do not connect the terminal blocks to the matrix card at this time.
3. Place the matrix card in slot 1 of the Model 707, but
do not slide it all the way into the mainframe.
WARNING
The following steps use high voltage (1OOV).Be
sure to remove power from the circuit before
making connection changes.
11. After allowing the reading on the Model 617 to settle,
verify that it is >lGO. This measurement is the leakage
resistance (isolation) of ROW A.
12. Place the Model 617 in standby and enable zero check.
13. Progmn the Model 707 to close crosspoint Al.
14. On the Model 617, disable zero check and press
OPERATE to source 1OOV.
15. After allowing the reading on the Model 617 to settle,
verify that it is also >lGR. This measurement checks
the isolation of COLUMN 1.
16. Using Table 4-3 as a guide, repeat the basic procedure
of steps I2 through I5 for the rest of the columns and
rows (test numbers 3 through 20 of the table).
17. Turn the Model 707 off and slide the matrix card out
of the mainframe far enough to gain access to the
prewired terminal block.
18. Remove the terminal block from the matrix card and
rewire the it as shown in Figure 4-8.
19. Repeat steps 7 through 16 to check common mode
isolation.
Table 4-3. Differential and Common Mode Isolation
Test
Test No.
4. On the Model 6I7, select the 2pA range, and enable
zero check and zero correct in that order. Leave zero
correct enabled for the entire procedure.
5. On the Model 617, set the voltage source for +l03V, and
select the 200x4 current range. Make sure the voltage
source is still in standby.
6. Place the Model 617 in the V/I measurement function
by pressing SHIFT OHMS.
7. With the Model 617 in standby, connect the pre-wired
terminal block to ROW A of the matrix card.
8. Feed the test leads through the cable clamp of the
matrix card and push the card all the way into the
mainframe. ‘lighten the two spring loaded screws to
completely mate the card with the backplane.
9. Turn on the Model 7W, but do not program any crosspoints to close. All crossuoints must be open.
10. On the Model 617. disable zero check and press
OPERATE to source 1OOV.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Differential
or
Common Mode Test
ROW A
COLUMN
COLUMN
COLUMN
COLUMN
COLUMN
COLUMN
COLUMN
COLUMN
COLUMN
COLUMN
COLUMN
COLUMN
ROW B
ROW C
ROW D
ROW E
ROW F
ROW G
ROW H
Cmsspoints
Closed
1
2
3
4
5
6
7
8
9
10
11
I2
Al
Al
Al
Al
Al
Al
Al
None
Al
A2
A3
A4
A5
A6
A7
A8
A9
Al0
All
Al2
and
and
and
and
and
and
and
Bl
Cl
Dl
El
Fl
Gl
Hl
411
SERVICE INFORMATION
1
L--~~-~~~~---------~~~~
Model
Figure 4-7. Differential
4-12
isolation
Testing
7071
Figure 4-8. Common Mode Isolation Testing
4.5 PRINCIPLES
OF OPERATION
The paragraphs below discuss the basic operating principles for the Model 7071 and can be used as an aid in
troubleshooting
the matrix card. The schematic drawing
of the matrix card is shown on drawing number 707l-106,
located at the end of Section 5.
4.5.1 Card Identification
Identification
coding and a matrix configuration
table is
stored in an erasable programmable read-only memory
(EPROM). This information is sent to the Model ilY so that
it “knows” which type of mahix card is installed in that
particular mainframe slot. This enables the Model 707 to
send valid configuration
data to the matrix card.
On power up, control line CARDSEL goes low turning on
the EPROM (U27). That con&o1 line, as well as the other
control lines from the Model 707 are buffered by U44. Lines
CLK, NEXT ADDR and CLR ADDR along with counter
U45 control the task of loading data from the EPROM into
the parallel to serial shift register (U43). Data sent from
U47 to the Model 707 via the IDDATA line is strobed by
the CLK control line. The timing diagram in Figure 4-9.
shows the first byte of identification
data during the
transfer sequence. For subsequent bytes, the CLRADDR
line stays low.
SERVICE INFORMATION
CLRADDR
NEXTADDR
I
r-l
LJ
CLK
IDDATA
I
Figure 4-9. IDDATA Timing Diagram
4.5.2 Switching
Circuitry
Matrix configuration
data is sent from the Model 707 via
the RELAY DATA control line and serially loaded into the
I2 shift registers (U3Cl through U41). The matrix card relays
configure accordingly
when the registers receive the
STROBE signal from the Model 707 A relay is energized
when a register output is low (connected to digital common). A register output is low when a “high” data bit is
clocked into it (i.e. inverting drivers).
4.5.3 Power Up Safeguard
To prevent relays from inadvertantly energizing and causing possible damage during power up, a safeguard circuit
has been incorporated into the design. The protection circuit is comprised of a dual NAND gate (U42) and an RC
network (Rl, C20 and CRI). The time constant of the RC
network keeps the the output of the NAND gate high during the power up sequence. This high signal is applied to
the OEN input of the shift registers keeping the relays deenergized. After the capacitor of the RC network charges,
a STROBE signal will then force the output of the NAND
gate low allowing configured relays to energize.
414
4.6 SPECIAL HANDLING
SENSITIVE DEVICES
OF STATIC-
CMOS and other high-impedance
devices are subject to
possible static discharge damage because of the highimpedance levels involved. The following precautions pertain specifically to static-sensitive devices. However, since
many devices in the Model 7U7l are static-sensitive, it is
recommended that they all be treated as static-sensitive.
1. Such devices should be transported and handled only
in containers specially designed to prevent or dissipate
static build-up. Typically, these devices will be received
in anti-static containers made of plastic or foam. Keep
these parts in their original containers until ready for
i”stalIatio”.
2. Revove the devices from their protective containers only
at a properly grounded work station. Also ground
yourself with a suitable wrist strap while working with
these devices.
3. Handle the devices only by the body; do not touch the
pins.
4. Any printed circuit board into which the device is to be
inserted must first be grounded to the bench or table.
tools and
5. Use only anti-static
type de-soldering
grounded-tip
soldering irons.
SERVICEINFORMATION
4.7 TROUBLESHOOTING
The Keithley Model 7070 Universal Adapter Card is an extender card that allows access to circuit components of the
Model 7071 during troubleshooting.
Also, Figure 410,
which provides receptacle contact identification,
is included as a troubleshooting
aid.
4.7.1 Recommended
Equipment
1. Disconnect the jumper wire from the matrix card
chassis. The wire is secured to the matrix card chassis
with a screw.
2. The rear shield is secured to the matrix card by eight
standoffs. Carefully slide the rear shield upward until
the eight standoffs align with the large clearance
holes in the shield and remove the shield.
3. To reinstall the shield, reverse the above procedure.
Make sure the metal side of the shield is facing
outward.
Table 4-4 summa&e s the equipment necessary for general
troubleshooting.
4.7.2 Troubleshooting
CAUTION
Failure to observe the following precautions
could result in damage not covered by the
warranty:
1. The shield must be installed such that the
metal side is tacing away horn the matrlx card.
Backward installation will cause PC board connections to short out agalnst the metal shield.
2. The jumper wire must be connected as
shown in order to prmrlde circuit protection horn
static discharge.
Procedure
In order to service the matrix card, it may be necessary
to remove the rear shield. Referring to Figure 411, perform
the following procedure to remove and reinstall the rear
shield:
Table 4-4.
Troubleshooting
Recommended
Table 4-5 outlines
matrix card.
Application
Description
DMh4 (Keithley
Equipment
Measure DC voltage
196)
Dual-trace, triggered
sweep oscilloscope, DC
to 5oMHz
Check clock and logic
Extender Card
(Keithley 7U70)
Allow
circuit access
Table 4-5. Tmubleshooting
=
1
2
3
4
5
6
7
8
9
10
the troubleshooting
procedure for the
CAUTION
Contamination will degrade the pertomtance of
the matrix card. To avoid contamination, always
grasp the card by the handle and side edges.
Do not touch the edge connectors of the card,
and do not touch the board surtaces or components. On “reck and panel” connectors and
quick disconnect terminal blocka, do not touch
areas adjacent to the electrical contacts.
Summary’
Item/Component
Comment
Required Condition
TFl
TP3
TP5
+6V supply
+5v supply
CLR ADDR line**
TP4
TP9
TP6
TPlO
TIT3
TIT
LJ30 thru U41,
pins 11 thru la
NEXT ADDR line*
CLK line
IDDATA line*
Power up safeguard
RELAY DATA line
STROBE line
Relay Drivers
+6V DC
+5V DC
High logic pulse at beginning of each card identification
transfer sequence (upon power up).
Low logic pulse before each byte transfer.
1.79MHz clock
Card identification logic pulse train (on power up).
Remains high during power up
Logic pulse train to load relay configuration
registers.
High logic pulse to strobe relay configuration
registers.
+6V for open crosspoints =OV for closed crosspoints
‘All measurements
*See Figure 4-9
referenced
byte
to digital common (TF2)
415
SERVICEINFORMATION
Figure 4-10. Receptacle Contact ldentlflcatlon
416
SERVICE INFORMATION
Figure 4-11. Rear Shield
4-v
SECTION 5
Replaceable Parts
5.1 INTRODUCTION
This section contains a list of replaceable electrical and
mechanical parts for the Model 707I, as well as a component layout drawing and schematic diagram of the matrix
card.
5.3 ORDERING
in
INFORMATION
To place a parts order, or to obtain information concerning replacement parts, contact your Keithley representative
or the factory (see the inside front cover for addresses).
When ordering parts, be sure to include the following
information:
1. Matrix card model number (7071)
2. Card serial number
5.4 FACTORY SERVICE
If the matrix card is to be returned to Keithley Instruments
for repair, perform the following:
5.2 PARTS LISTS
Electrical parts are listed in order of circuit designation
Table 5-l. Table 5-2 summarizes miscellaneous parts.
3. Part description
4. Circuit description, if applicable
5. Keithley part number
1. Complete the service form at the back of this manual
and include it with the card.
2. Carefully pack the card in the original packing carton.
3. Write ATTENTION REPAIR DEPT on the shipping label.
Note: It is not necessary to return the matrix mainframe
with the card.
5.5 COMPONENT
DIAGRAM
LAYOUT AND SCHEMATIC
Figure 5-l shows a component layout of the Model 7071,
while Figure 5-2 shows a schematic diagram.
5-115-2
TABLE
5-1.
CIRCUIT
DESIG.
MODEL
7071,
PARTS
LIST
KEITHLEY
PART NO.
DESCRIPTION
CAP,10uF;20+100%,25V,ALUM
CAP,47uF,lO%,lGV,ALUM
ELEC
CAP..O~~F.~~%,~~V,CEFIAM~C
ELEC
c-314-10
C-321 -47
C-237-.01
C16..C19
c20
c21 ,c22
C23..C34
C35.C36
c37
C6..C8,Cl&C17.
CAP,270pF,20%,100V,CERAMIC/FERRITE
CAP,.O1uF,l0%,1000V,CERAMIC
CAP,.luF,20%,50V,CERAMlC
C-386.270P
C-64-.01
C-365-.1
CR1
CR2
DIODE,SILICON,1N4148
DIODE,SCHO~KY,1N5711
RF-26
RF-69
Jl ..JZO
J21 ,J22
CONN,3 PIN
SOCKETCONNECTOR
cs-570-3
cs-593
Kl ..K96
RELAY
RL-67
Fil
R2
R3
R4
R5
R6
RES,47K,5%,1/4W,COMPOSITION
RES,1OK,5%,1/4W.COMPOSITION
RES,120K.5%.1/4W.COMPOSITION
RES,l lK,5%,1/4W,COMPOSlTlON
RES,910.5%,1NW,COMPOSITION
RES.200.5%.1/4W.COMPOSlTlON
TPl..TPlO
CONN,TEST
U27
u3o..u41
U42
u43
u44
u45
PROGRAM
IC&BIT
SERIAL-INILTCH
DRIVE.UCN-5841A
IC,QUAD 2 INPUT NAND,74HCTOO
IC,8 BIT PARALLEL TO SERIAL.74HCT165
IC,OCTAL BUFFER/LINE
DRIVER,74HCT244
IC,12 STAGE BINARY COUNTER,74HCT4040
7071.800
IC-536
IC-399
IC-548
IC-489
IC-545
WI
STIFFENER.BOARD
J-16
(DO-35)
OR FILM
OR FILM
OR FILM
OR FILM
OR FILM
OR FILM
POINT
R-76.47K
R-76-1 OK
R-76.t20K
R-76-1 1K
R-76-910
R-76-200
65.553
TABLE
5-2. MODEL
7071, MISCELLANEOUS,
PARTS LIST
QUANTITY
DESCRIPTION
2
2
2
UPPER CLAM’ ASSEMBLY
UPPER CLAMP
RUBBER STRIP
7071-30s
7071-307-I
2
2
2
LOWER CLAMP ASSEMBLY
LOWER CLAMP
RUBBER STRIF
7071-306
7071-307-l
1
1
1
1
8
HANDLE
CONNECI-OR STRIP
SOCKET (FOR U27)
SHIELD. REAR
STANDOFFS
HH-33-1
CS-576.60
SO-69
7071-311
7071-310
KEITHLEY
PART NO.
Figure 6-2. Model 7071 Schematic Diagram, Dwg. No. 7071-106
(sheet 1 of 4)
.--,
L
-
I
!
,
J
1
t
1
3
\
n
Service Form
Model
Serial No.
No.
Name and Telephone
Date
No.
Company
List all control settings, de&be
problem and check boxes that apply to problem.
m Intermittent
B Analog output follows display
0
a
0
0 Obvious problem on power-up
0 All ranges or functions are bad
B Batteries and fuses are OK
0 Checked all cables
IEEEfailure
Front panel operational
Particular range or function bad; specify
Display or output (check one)
LIDlifts
0 Unstable
0 Overload
0 Unable to zero
0 Will not read applied input
0 Certificate of calibration required
cl Calibration only
0 Data required
(attach any additional sheets as necessary)
Show a block diagram of your measurement system including all ins’nwnents connected (whether power is tuned on or not).
Also, d&be
signal source.
Where is the measurement being performed? (factory, controlled laboratory, out-of-doors, etc.)
Ambient temperature?
Whaf power lie voltage is used?
Relative humidity?
Other?
Any additional information. (If special modifications have been made by the user, please describe.)
“F
Keithley Instruments, Inc.
28775 Aurora Road
Cleveland, Ohio 44139
Printed in the U.S.A
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