Keithley 708A User manual

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Model 708A
Switching System
Instruction Manual
Contains Operating and Servicing Information
708A-901-01 / A
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WARRANTY
Keithley Instruments, Inc. warrants this product to be free from defects in material and workmanship for a period of 1 year from date of
shipment.
Keithley Instruments, Inc. warrants the following items for 90 days from the date of shipment: probes, cables, rechargeable batteries,
diskettes, and documentation.
During the warranty period, we will, at our option, either repair or replace any product that proves to be defective.
To exercise this warranty, write or call your local Keithley representative, or contact Keithley headquarters in Cleveland, Ohio.You will
be given prompt assistance and return instructions. Send the product, transportation prepaid, to the indicated service facility. Repairs
will be made and the product returned, transportation prepaid. Repaired or replaced products are warranted for the balance of the origi-
nal warranty period, or at least 90 days.
LIMITATION OF WARRANTY
This warranty does not apply to defects resulting from product modification without Keithley’s express written consent, or misuse of
any product or part. This warranty also does not apply to fuses, software, non-rechargeable batteries, damage from battery leakage, or
problems arising from normal wear or failure to follow instructions.
THIS WARRANTY IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESSED OR IMPLIED, INCLUDING ANY IMPLIED
WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE. THE REMEDIES PROVIDED HEREIN ARE
BUYER’S SOLE AND EXCLUSIVE REMEDIES.
NEITHER KEITHLEY INSTRUMENTS, INC. NOR ANY OF ITS EMPLOYEES SHALL BE LIABLE FOR ANY DIRECT, INDI-
RECT, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGESARISING OUT OF THE USE OF ITS INSTRUMENTSAND
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.
Keithley Instruments, Inc. • 28775 Aurora Road • Cleveland, OH 44139 • 440-248-0400 • Fax: [phone] • http://www.keithley.com
CHINA: Keithley Instruments China •Yuan Chen Xin Building, Room 705 • 12Yumin Road, Dewai, Madian • Beijing 100029 • 8610-62022886 • Fax: [phone]
FRANCE: Keithley Instruments SARL • BP 60 • 3 Allée des Garays • 91122 Palaiseau Cédex • 33-1-60-11-51-55 • Fax: [phone]
GERMANY: Keithley Instruments GmbH • Landsberger Strasse 65 • D-82110 Germering, Munich • 49-89-8493070 • Fax: [phone]
GREAT BRITAIN: Keithley Instruments, Ltd. • The Minster • 58 Portman Road • Reading, Berkshire RG30 1EA • 44-1189-596469 • Fax: [phone]
ITALY: Keithley Instruments SRL • Viale S. Gimignano 38 • 20146 Milano • 39-2-48303008 • Fax: [phone]
NETHERLANDS: Keithley Instruments BV • Avelingen West 49 • 4202 MS Gorinchem • 31-(0)183-635333 • Fax: [phone]
SWITZERLAND: Keithley Instruments SA • Kriesbachstrasse 4 • 8600 Dübendorf • 41-1-8219444 • Fax: [phone]
TAIWAN: Keithley Instruments Taiwan • 1FL., 85 Po Ai Street • Hsinchu, Taiwan • 886-35-778462 • Fax: [phone]
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Model 708A Switching System
Instruction Manual
©1998, Keithley Instruments, Inc.
All rights reserved.
Cleveland, Ohio, U.S.A.
First Printing, September 1998
Document Number: 708A-901-01 Rev. A
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Manual Print History
The print history shown below lists the printing dates of all Revisions and Addenda created for this manual. The Revision
Level letter increases alphabetically as the manual undergoes subsequent updates.Addenda, which are released between Revi-
sions, contain important change information that the user should incorporate immediately into the manual. Addenda are num-
bered sequentially. When a new Revision is created, all Addenda associated with the previous Revision of the manual are
incorporated into the new Revision of the manual. Each new Revision includes a revised copy of this print history page.
RevisionA (Document Number 708A-901-01).............................................................................. September 1998
All Keithley product names are trademarks or registered trademarks of Keithley Instruments, Inc.
Other brand and product names are trademarks or registered trademarks of their respective holders.
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Safety Precautions
The following safety precautions should be observed before using
this product and any associated instrumentation.Although some in-
struments and accessories would normally be used with non-haz-
ardous voltages, there are situations where hazardous conditions
may be present.
This product is intended for use by qualified personnel who recog-
nize shock hazards and are familiar with the safety precautions re-
quired to avoid possible injury. Read the operating information
carefully before using the product.
The types of product users are:
Responsible body is the individual or group responsible for the use
and maintenance of equipment, and for ensuring that operators are
adequately trained.
Operators use the product for its intended function. They must be
trained in electrical safety procedures and proper use of the instru-
ment. They must be protected from electric shock and contact with
hazardous live circuits.
Maintenancepersonnel perform routine procedures on the product
to keep it operating, for example, setting the line voltage or replac-
ing consumable materials. Maintenance procedures are described in
the manual. The procedures explicitly state if the operator may per-
form them. Otherwise, they should be performed only by service
personnel.
Service personnel are trained to work on live circuits, and perform
safe installations and repairs of products. Only properly trained ser-
vice personnel may perform installation and service procedures.
Exercise extreme caution when a shock hazard is present. Lethal
voltage may be present on cable connector jacks or test fixtures.The
American National Standards Institute (ANSI) states that a shock
hazard exists when voltage levels greater than 30V RMS, 42.4V
peak,or60VDCarepresent.
Agoodsafetypracticeistoexpect
thathazardousvoltageispresentinanyunknowncircuitbefore
measuring.
Users of this product must be protected from electric shock at all
times. The responsible body must ensure that users are prevented
access and/or insulated from every connection point. In some cases,
connections must be exposed to potential human contact. Product
users in these circumstances must be trained to protect themselves
from the risk of electric shock. If the circuit is capable of operating
at or above 1000 volts,
no conductive part of the circuit may be
exposed.
As described in the International Electrotechnical Commission
(IEC) Standard IEC 664, digital multimeter measuring circuits
(e.g., Keithley Models 175A, 199, 2000, 2001, 2002, and 2010) are
Installation Category II. All other instruments’signal terminals are
Installation Category I and must not be connected to mains.
Do not connect switching cards directly to unlimited power circuits.
They are intended to be used with impedance limited sources.
NEVER connect switching cards directly to AC mains. When con-
necting sources to switching cards, install protective devices to lim-
it fault current and voltage to the card.
Before operating an instrument, make sure the line cord is connect-
ed to a properly grounded power receptacle. Inspect the connecting
cables, test leads, and jumpers for possible wear, cracks, or breaks
before each use.
For maximum safety, do not touch the product, test cables, or any
other instruments while power is applied to the circuit under test.
ALWAYS remove power from the entire test system and discharge
any capacitors before: connecting or disconnecting cables or jump-
ers, installing or removing switching cards, or making internal
changes, such as installing or removing jumpers.
Do not touch any object that could provide a current path to the
common side of the circuit under test or power line (earth) ground.
Always make measurements with dry hands while standing on a
dry, insulated surface capable of withstanding the voltage being
measured.
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Do not exceed the maximum signal levels of the instruments and ac-
cessories, as defined in the specifications and operating informa-
tion, and as shown on the instrument or test fixture panels, or
switching card.
When fuses are used in a product, replace with same type and rating
for continued protection against fire hazard.
Chassis connections must only be used as shield connections for
measuring circuits, NOT as safety earth ground connections.
If you are using a test fixture, keep the lid closed while power is ap-
plied to the device under test. Safe operation requires the use of a
lid interlock.
If a screw is present, connect it to safety earth ground using the
wire recommended in the user documentation.
The symbol on an instrument indicates that the user should re-
fer to the operating instructions located in the manual.
The symbol on an instrument shows that it can source or mea-
sure 1000 volts or more, including the combined effect of normal
and common mode voltages. Use standard safety precautions to
avoid personal contact with these voltages.
The
WARNING heading in a manual explains dangers that might
result in personal injury or death.Always read the associated infor-
mation very carefully before performing the indicated procedure.
The
CAUTION heading in a manual explains hazards that could
damage the instrument. Such damage may invalidate the warranty.
Instrumentation and accessories shall not be connected to humans.
Before performing any maintenance, disconnect the line cord and
all test cables.
To maintain protection from electric shock and fire, replacement
components in mains circuits, including the power transformer, test
leads, and input jacks, must be purchased from Keithley Instru-
ments. Standard fuses, with applicable national safety approvals,
may be used if the rating and type are the same. Other components
that are not safety related may be purchased from other suppliers as
long as they are equivalent to the original component. (Note that se-
lected parts should be purchased only through Keithley Instruments
to maintain accuracy and functionality of the product.) If you are
unsure about the applicability of a replacement component, call a
Keithley Instruments office for information.
To clean the instrument, use a damp cloth or mild, water based
cleaner. Clean the exterior of the instrument only. Do not apply
cleaner directly to the instrument or allow liquids to enter or spill
on the instrument.
!
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708A Switching System
Overview
CAPACITY: One plug-in card per mainframe
EXPANSION CAPACITY: Daisy-chain expansion of up to four Slave units with one
Master unit.
ANALOG BACKPLANES: Connections provided for user-supplied cable. Provides
automatic row expansions between 7071, 7071-4, 7073, 7074, 7075, 7076 and 7077
cards in separate 708 mainframes.
DISPLAY: Crosspoint and IEEE-488 bus status.
MEMORY: Storage for 100 matrix setups, battery backup.
PROGRAMMED SETTLING TIME: 0 to 65 seconds in 1ms increments.
FRONT PANEL CONTROL: Crosspoint Control, Factory Default, Open, and Digital I/O.
TRIGGER SOURCES: External Trigger (TTL compatible, programmable edge, 600ns
minimum pulse width); IEEE-488 bus (TALK, GET, “X”); manual.
STATUS OUTPUT: Matrix Ready (TTL compatible programmable high or low true);
goes false when relays are switched, true at end of Programmed Settling Time.
MAKE BEFORE BREAK, BREAK BEFORE MAKE: Programmable by row.
LIGHT PEN OPTION: Controls crosspoints.
Execution Speed
MAXIMUM TRIGGER RATE: 200 setups per second (stepping through previously
stored setups with make-before-break and break-before make disabled)
TRIGGER RESPONSE TIME: External trigger: <1ms. IEEE-488 GET: <1ms.
RESPONSE TO IEEE-488 COMMAND (to close a single relay, excluding relay settling
time):
Standalone: <15ms.
Master and Four Slaves: <55ms.
Download Time (one setup): 50ms typical.
IEEE-488 BUS IMPLEMENTATION
MULTILINE COMMANDS: DCL, LLO, SDC, GET, GTL, UNT, UNL, SPE, SPD.
UNILINE COMMANDS: IFC, REN, EOI, SRQ, ATN.
INTERFACE FUNCTIONS: SH1, AH1, T6,TE0, L4, LE0, SR1, RL1, PP0, DC1, DT1, C0, E1.
GENERAL
CARD INSTALLATION: Configurable for front or rear installation.
DIGITAL I/O:
OUTPUTS:
Configuration: 16 open collector drivers with factory-installed 10kΩpull-up
resistors. Each driver has internal flyback diodes.
Pull-upVoltage: 5V @ 65mA internally supplied. External connection provided for
user supplied voltage 40V max.
Maximum Sink Current: 600mA per channel. 2A max.
Output Protection: Each output protected from short circuits with supply
voltages up to 25VDC.
Logic: Negative true.
Collector-Emitter Saturation Voltage: <200mV @ 100mA
<400mV @ 400mA
<600mV @ 600mA
INPUTS:
Configuration: 16 inputs with internal 10kΩpull-up resistor.
Maximum Voltage Level: 42V pk.
Logic: Positive true logic.
REAR PANEL CONNECTORS:
Two BNC: External Trigger, Matrix Ready.
Two DB-25: Digital I/O.
Two 8-pin DIN: Master/Slave In, Master/Slave Out.
EMC: Conforms with European Union Directive 89/336/EEC EN 55011,
EN 50082-1, EN 61000-3-3, FCC part 15 class B.
SAFETY: Conforms with European Union Directive 73/23/EEC EN 61010-1.
ENVIRONMENT:
Operating: 0 to 50°C, <80% relative humidity (0° to 35°C).
Storage: –25 to 65°C.
POWER: 100–240V AC, 50–60Hz, 110 VA maximum.
RELAY DRIVE: 5A.
DIMENSIONS: 90mm high ×433 mm wide ×570 mm deep (3.5 in ×17 in ×22.4 in).
Specifications are subject to change without notice.
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1 General Information
1.1 Introduction ........................................................................................................................................................ 1-1
1.2 Features .............................................................................................................................................................. 1-1
1.3 Warranty information ......................................................................................................................................... 1-1
1.4 Manual addenda ................................................................................................................................................. 1-1
1.5 Safety symbols and terms .................................................................................................................................. 1-1
1.6 Specifications ..................................................................................................................................................... 1-2
1.7 Unpacking and inspection .................................................................................................................................. 1-2
1.7.1 Inspection for damage .............................................................................................................................. 1-2
1.7.2 Shipment contents .................................................................................................................................... 1-2
1.8 Repacking for shipment ..................................................................................................................................... 1-2
1.9 Optional accessories ........................................................................................................................................... 1-2
2 Card Installation
2.1 Introduction ........................................................................................................................................................ 2-1
2.2 Changing card installation access ...................................................................................................................... 2-1
2.3 Card installation/removal ................................................................................................................................... 2-2
3 Getting Started
3.1 Introduction ........................................................................................................................................................ 3-1
3.2 Front panel familiarization ................................................................................................................................. 3-1
3.2.1 LED matrix .............................................................................................................................................. 3-2
3.2.2 Light pen connection ................................................................................................................................ 3-3
3.2.3 LED indicators ......................................................................................................................................... 3-3
3.2.4 Switches/connections ............................................................................................................................... 3-3
3.3 Rear panel familiarization .................................................................................................................................. 3-4
3.4 Card connections ................................................................................................................................................ 3-6
3.4.1 Overview — matrix design considerations .............................................................................................. 3-6
3.4.2 Connections — instruments to rows ........................................................................................................ 3-6
3.4.3 Connections — instruments to columns .................................................................................................. 3-8
3.4.4 Connections — partial matrix expansion ................................................................................................. 3-8
3.4.5 Multiple application cards ........................................................................................................................ 3-8
3.5 Expanding matrix size ...................................................................................................................................... 3-10
3.5.1 Overview — multiple matrix expansion ................................................................................................ 3-10
3.5.2 Backplane row expansion ...................................................................................................................... 3-14
3.5.3 External expansion ................................................................................................................................. 3-14
3.5.4 Control expansion using master/slave configuration ............................................................................. 3-15
3.5.5 System expansion issues ........................................................................................................................ 3-18
Table of Contents
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3.5.6 Documenting system configuration ....................................................................................................... 3-18
3.5.7 Analog backplane cable construction .................................................................................................... 3-20
3.5.8 Sample expanded matrices .................................................................................................................... 3-20
3.6 Basic switching overview ................................................................................................................................ 3-24
3.6.1 Power-up ................................................................................................................................................ 3-24
3.6.2 Selecting make/break and break/make rows .......................................................................................... 3-24
3.6.3 Modifying a relay setup ......................................................................................................................... 3-24
3.6.4 Storing relay setup and applying setup to relays ................................................................................... 3-24
4 Operation
4.1 Introduction ........................................................................................................................................................ 4-1
4.2 Setup data paths ................................................................................................................................................. 4-1
4.3 Power-up procedure ........................................................................................................................................... 4-2
4.3.1 Line power connections ........................................................................................................................... 4-2
4.3.2 Power switch ............................................................................................................................................ 4-2
4.3.3 Power-up self-test and error conditions ................................................................................................... 4-2
4.3.4 Power-up configuration ........................................................................................................................... 4-3
4.3.5 Master/slave power-up ............................................................................................................................. 4-3
4.4 Display ............................................................................................................................................................... 4-4
4.4.1 Error LED ................................................................................................................................................ 4-4
4.4.2 IEEE-488 status indicators ...................................................................................................................... 4-4
4.4.3 Crosspoint display LEDs ......................................................................................................................... 4-5
4.4.4 Light pen .................................................................................................................................................. 4-5
4.5 Crosspoint display ............................................................................................................................................. 4-6
4.5.1 Modifying ................................................................................................................................................ 4-6
4.5.2 Copying .................................................................................................................................................... 4-6
4.6 Operation control ............................................................................................................................................... 4-7
4.6.1 Digital I/O ports ....................................................................................................................................... 4-7
4.6.2 External trigger ........................................................................................................................................ 4-8
4.6.3 Matrix ready output ................................................................................................................................. 4-8
4.6.4 Stand-alone and master/slave .................................................................................................................. 4-9
4.6.5 IEEE-488 bus address ............................................................................................................................ 4-10
4.6.6 Hardware relay settling times ................................................................................................................ 4-10
4.6.7 Self-test .................................................................................................................................................. 4-10
4.6.8 Factory defaults ..................................................................................................................................... 4-10
4.7 Selecting switching parameters ....................................................................................................................... 4-10
4.7.1 Programmed settling times .................................................................................................................... 4-11
4.7.2 Make/break and break/make rows ......................................................................................................... 4-11
4.8 Triggering ........................................................................................................................................................ 4-11
4.8.1 Sources ................................................................................................................................................... 4-12
4.8.2 Overrun conditions ................................................................................................................................ 4-12
4.8.3 External trigger input ............................................................................................................................. 4-14
4.8.4 Matrix ready output ............................................................................................................................... 4-14
4.8.5 IEEE-488 bus triggering ........................................................................................................................ 4-15
4.9 Reset ................................................................................................................................................................ 4-15
5 IEEE-488 Programming
5.1 Introduction ........................................................................................................................................................ 5-1
5.2 IEEE-488 quick start .......................................................................................................................................... 5-1
5.3 Bus cable connections ........................................................................................................................................ 5-3
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5.4 Interface function codes ..................................................................................................................................... 5-5
5.5 Primary address programming ........................................................................................................................... 5-5
5.6 QuickBASIC programming ............................................................................................................................... 5-6
5.7 Indicator and control aspects of IEEE-488 operation ........................................................................................ 5-7
5.7.1 Error LED ................................................................................................................................................ 5-7
5.7.2 Status indicators ....................................................................................................................................... 5-8
5.7.3 LOCAL/DIGITAL I/O key ...................................................................................................................... 5-9
5.7.4 Concurrent front panel and bus operation ................................................................................................ 5-9
5.8 General bus command programming ................................................................................................................. 5-9
5.8.1 Overview .................................................................................................................................................. 5-9
5.8.2 REN (remote enable) ............................................................................................................................... 5-9
5.8.3 IFC (interface clear) ............................................................................................................................... 5-10
5.8.4 LLO (local lockout) ............................................................................................................................... 5-10
5.8.5 GTL (go to local) ................................................................................................................................... 5-10
5.8.6 DCL (device clear) ................................................................................................................................. 5-10
5.8.7 SDC (selective device clear) .................................................................................................................. 5-10
5.8.8 GET (group execute trigger) .................................................................................................................. 5-10
5.8.9 SPE, SPD (serial polling) ....................................................................................................................... 5-10
5.9 Device-dependent command (DDC) programming ......................................................................................... 5-11
5.9.1 Overview ................................................................................................................................................ 5-11
5.9.2 A — External trigger .............................................................................................................................. 5-15
5.9.3 B — Matrix ready .................................................................................................................................. 5-16
5.9.4 C — Close crosspoint ............................................................................................................................ 5-17
5.9.5 D — Digital Output ................................................................................................................................ 5-17
5.9.6 E — Edit pointer .................................................................................................................................... 5-18
5.9.7 F — Enable/disable triggers ................................................................................................................... 5-18
5.9.8 G — Data format .................................................................................................................................... 5-19
5.9.9 I — Insert blank setup ............................................................................................................................ 5-24
5.9.10 J — Self-test ........................................................................................................................................... 5-24
5.9.11 K — EOI and hold-off ........................................................................................................................... 5-24
5.9.12 L — Download setups ............................................................................................................................ 5-25
5.9.13 M — SRQ and serial poll byte ............................................................................................................... 5-26
5.9.14 N — Open crosspoint ............................................................................................................................. 5-28
5.9.15 O — Digital output ................................................................................................................................ 5-28
5.9.16 P — Clear crosspoints ............................................................................................................................ 5-29
5.9.17 Q — Delete setup ................................................................................................................................... 5-29
5.9.18 R — Restore defaults ............................................................................................................................. 5-30
5.9.19 S — Programmed settling time .............................................................................................................. 5-30
5.9.20 T — Trigger ........................................................................................................................................... 5-31
5.9.21 U — Status ............................................................................................................................................. 5-32
5.9.22 V — Make/Break ................................................................................................................................... 5-36
5.9.23 W — Break/Make .................................................................................................................................. 5-37
5.9.24 X — Execute .......................................................................................................................................... 5-38
5.9.25 Y — Terminator ..................................................................................................................................... 5-38
5.9.26 Z — Copy setup ..................................................................................................................................... 5-39
5.10 Relay command combinations ......................................................................................................................... 5-40
5.11 Timing considerations ...................................................................................................................................... 5-40
6 Principles of Operation
6.1 Introduction ........................................................................................................................................................ 6-1
6.2 Overview ............................................................................................................................................................ 6-1
6.3 Microcomputer ................................................................................................................................................... 6-2
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6.3.1 Reset circuit ............................................................................................................................................. 6-3
6.3.2 Address decoding ..................................................................................................................................... 6-3
6.3.3 Memory .................................................................................................................................................... 6-3
6.4 Relay control circuitry ....................................................................................................................................... 6-4
6.4.1 Switching card interface .......................................................................................................................... 6-4
6.4.2 Switching card logic ................................................................................................................................ 6-6
6.5 Display circuitry ................................................................................................................................................ 6-8
6.5.1 Display data ........................................................................................................................................... 6-11
6.5.2 Front panel keys ..................................................................................................................................... 6-11
6.5.3 Display interface .................................................................................................................................... 6-11
6.5.4 Refresh display/read keyboard .............................................................................................................. 6-11
6.6 Light pen interface ........................................................................................................................................... 6-12
6.7 Master/slave circuitry ...................................................................................................................................... 6-13
6.7.1 Serial communication ............................................................................................................................ 6-13
6.7.2 Control signals ....................................................................................................................................... 6-14
6.8 Digital I/O ........................................................................................................................................................ 6-14
6.9 IEEE-488 bus interface .................................................................................................................................... 6-14
6.10 Power supplies ................................................................................................................................................. 6-14
7 Maintenance
7.1 Introduction ........................................................................................................................................................ 7-1
7.2 Fixed rack installation ........................................................................................................................................ 7-1
7.3 Cover removal ................................................................................................................................................... 7-4
7.4 Fuse/power supply replacement ........................................................................................................................ 7-4
7.5 Battery replacement ........................................................................................................................................... 7-5
7.6 Digital I/O power selection (jumper W101) ...................................................................................................... 7-6
7.7 Disassembly ....................................................................................................................................................... 7-7
7.8 Static sensitive devices ...................................................................................................................................... 7-7
7.9 Switching system troubleshooting ..................................................................................................................... 7-8
7.9.1 Recommended test equipment ................................................................................................................. 7-8
7.9.2 Power-up self-test .................................................................................................................................... 7-8
7.9.3 Power supply checks ................................................................................................................................ 7-9
7.9.4 Mother board checks ................................................................................................................................ 7-9
7.9.5 Display checks ....................................................................................................................................... 7-13
7.9.6 Using an extender card .......................................................................................................................... 7-13
7.10 Handling and cleaning ..................................................................................................................................... 7-13
8 Replaceable Parts
8.1 Introduction ........................................................................................................................................................ 8-1
8.2 Parts lists ............................................................................................................................................................ 8-1
8.3 Ordering information ......................................................................................................................................... 8-1
8.4 Factory service ................................................................................................................................................... 8-1
8.5 Component layouts and schematics ................................................................................................................... 8-1
A Card Configuration Worksheet
B I/O Connections
B.1 Typical output connection schemes ................................................................................................................... B-1
B.2 Typical input connection scheme ...................................................................................................................... B-2
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C IEEE-488 Bus Overview
C.1 Introduction ....................................................................................................................................................... C-1
C.2 Bus description .................................................................................................................................................. C-1
C.3 Bus lines ............................................................................................................................................................ C-3
C.3.1 Data lines ................................................................................................................................................. C-3
C.3.2 Bus management lines ............................................................................................................................ C-3
C.3.3 Handshake lines ...................................................................................................................................... C-3
C.4 Bus commands .................................................................................................................................................. C-4
C.4.1 Uniline commands .................................................................................................................................. C-4
C.4.2 Universal multiline commands ............................................................................................................... C-5
C.4.3 Addressed multiline commands .............................................................................................................. C-5
C.4.4 Address commands ................................................................................................................................. C-5
C.4.5 Unaddress commands ............................................................................................................................. C-5
C.4.6 Command codes ...................................................................................................................................... C-5
C.4.7 Typical command sequences .................................................................................................................. C-7
C.4.8 IEEE command groups ........................................................................................................................... C-7
C.5 Interface function codes .................................................................................................................................... C-8
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2 Card Installation
Figure 2-1 Model 708A switching system – changing switch card installation .......................................................... 2-2
Figure 2-2 Matrix card installation .............................................................................................................................. 2-3
3 Getting Started
Figure 3-1 Model 708A front panel switches .............................................................................................................. 3-1
Figure 3-2 Setup data transfers .................................................................................................................................... 3-2
Figure 3-3 Digital I/O status display ............................................................................................................................ 3-2
Figure 3-4 Front panel ................................................................................................................................................. 3-4
Figure 3-5 Model 708A rear panel .............................................................................................................................. 3-5
Figure 3-6 Connecting instruments to rows – single switching system ...................................................................... 3-7
Figure 3-7 Connecting instruments to rows – multiple (two) switching systems ....................................................... 3-7
Figure 3-8 Connecting instruments to columns – multiple (two) switching systems .................................................. 3-9
Figure 3-9 Partial matrix expansion example ............................................................................................................ 3-10
Figure 3-10 Sample backplane expansion ................................................................................................................... 3-11
Figure 3-11 Sample external (to backplane) expansion ............................................................................................... 3-12
Figure 3-12 Sample of master/slave interconnect cables – five Model 708A switching systems ............................... 3-16
Figure 3-13 Master/slave column locations ................................................................................................................. 3-17
Figure 3-14 Analog backplane expansion connectors ................................................................................................. 3-20
Figure 3-15 Backplane expansion cable – five Model switching systems .................................................................. 3-21
Figure 3-16 External row expansion – two stand-alone Model 708A’s ...................................................................... 3-22
Figure 3-17 Sample backplane expansion ................................................................................................................... 3-23
Figure 3-18 Partial matrix expansion example ............................................................................................................ 3-24
4 Operation
Figure 4-1 Paths for relay setup data ........................................................................................................................... 4-1
Figure 4-2 IEEE-488 status indicators ......................................................................................................................... 4-4
Figure 4-3 Crosspoint display LEDs ........................................................................................................................... 4-5
Figure 4-4 Light pen .................................................................................................................................................... 4-6
Figure 4-5 Pinouts – digital I/O ports .......................................................................................................................... 4-7
Figure 4-6 Input/output configurations ........................................................................................................................ 4-7
Figure 4-7 Rear panel BNC jacks ................................................................................................................................ 4-8
Figure 4-8 Sample external trigger pulses ................................................................................................................... 4-8
Figure 4-9 Sample matrix ready pulses ....................................................................................................................... 4-8
Figure 4-10 Master/slave connectors ............................................................................................................................. 4-9
Figure 4-11 Rear panel – IEEE-488 address switches ................................................................................................... 4-9
Figure 4-12 IEEE-488 bus connector and rotary selection switches ........................................................................... 4-10
Figure 4-13 Timing without make/break and break/make rows .................................................................................. 4-12
Figure 4-14 Timing with either make/break or break/make rows ............................................................................... 4-13
Figure 4-15 Timing with both make/break and break/make rows ............................................................................... 4-14
List of Illustrations
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viii
5 IEEE-488 Programming
Figure 5-1 Flowchart of example program .................................................................................................................. 5-2
Figure 5-2 IEEE-488 connector ................................................................................................................................... 5-3
Figure 5-3 IEEE-488 connections ............................................................................................................................... 5-3
Figure 5-4 IEEE-488 connector location ..................................................................................................................... 5-4
Figure 5-5 Contact assignments .................................................................................................................................. 5-4
Figure 5-6 IEEE-488 bus connector and rotary selection switches ............................................................................. 5-6
Figure 5-7 IEEE-488 indicators ................................................................................................................................... 5-8
Figure 5-8 Digital I/O status display mode ................................................................................................................. 5-9
Figure 5-9 External trigger pulse ............................................................................................................................... 5-15
Figure 5-10 Matrix ready pulse ................................................................................................................................... 5-16
Figure 5-11 G0 and G1 full output formats ................................................................................................................. 5-21
Figure 5-12 G2 and G3 inspect output formats ........................................................................................................... 5-22
Figure 5-13 G4 and G5 condensed output formats ..................................................................................................... 5-22
Figure 5-14 G6 and G7 binary output formats ............................................................................................................ 5-23
Figure 5-15 SRQ mask and serial poll byte format ..................................................................................................... 5-26
Figure 5-16 READY and MATRIX READY signal timing ....................................................................................... 5-31
Figure 5-17 U0 machine status word ........................................................................................................................... 5-33
Figure 5-18 U1 error status word ................................................................................................................................ 5-33
Figure 5-19 U3 relay step pointer ................................................................................................................................ 5-34
Figure 5-20 U4 number of slaves ................................................................................................................................ 5-35
Figure 5-21 U5 card identification .............................................................................................................................. 5-35
Figure 5-22 U6 relay settling time ............................................................................................................................... 5-35
Figure 5-23 U7 digital input ........................................................................................................................................ 5-36
6 Principles of Operation
Figure 6-1 Model 708A block diagram ....................................................................................................................... 6-1
Figure 6-2 Digital board block diagram ...................................................................................................................... 6-2
Figure 6-3 RAM and battery backup ........................................................................................................................... 6-4
Figure 6-4 Matrix card interface simplified schematic ............................................................................................... 6-5
Figure 6-5 Matrix card interface timing diagram ........................................................................................................ 6-6
Figure 6-6 Typical matrix card logic block diagram ................................................................................................... 6-7
Figure 6-7 IDDATA timing diagram .......................................................................................................................... 6-7
Figure 6-8 Display board block diagram ..................................................................................................................... 6-9
Figure 6-9 Display interface simplified schematic ...................................................................................................... 6-9
Figure 6-10 Light pen interface simplified schematic ................................................................................................. 6-12
Figure 6-11 Master/slave interface simplified schematic ............................................................................................ 6-13
Figure 6-12 Digital I/O interface simplified schematic ............................................................................................... 6-15
7 Maintenance
Figure 7-1 Rack installation ........................................................................................................................................ 7-2
Figure 7-2 Screw and dress panel removal .................................................................................................................. 7-4
Figure 7-3 W101 jumper location ............................................................................................................................... 7-6
Figure 7-4 Troubleshooting programs ......................................................................................................................... 7-8
Figure 7-5 Relay control waveforms ......................................................................................................................... 7-12
Figure 7-6 Display interface waveforms ................................................................................................................... 7-12
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ix
B I/O Connections
Figure B-1 Digital output, solenoid control ................................................................................................................ B-1
Figure B-2 Digital output, relay control ...................................................................................................................... B-1
Figure B-3 Digital output, motor control .................................................................................................................... B-2
Figure B-4 Digital output, logic device control ........................................................................................................... B-2
Figure B-5 Digital input, monitoring micro-switches ................................................................................................. B-2
C IEEE-488 Bus Overview
Figure C-1 IEEE-488 bus configuration ...................................................................................................................... C-2
Figure C-2 IEEE-488 handshake sequence ................................................................................................................. C-3
Figure C-3 Command codes ........................................................................................................................................ C-6
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xi
3 Getting Started
Table 3-1 Digital input display formats ...................................................................................................................... 3-3
Table 3-2 Digital output display formats .................................................................................................................... 3-3
Table 3-3 IEEE-488 address switches ........................................................................................................................ 3-5
Table 3-4 Matrix and multiplexer cards ..................................................................................................................... 3-6
Table 3-5 Row-column and column-column paths .................................................................................................... 3-8
Table 3-6 Matrix expansion ...................................................................................................................................... 3-13
Table 3-7 Model 708A external expansion cables ................................................................................................... 3-15
Table 3-8 Response time comparison ....................................................................................................................... 3-18
Table 3-9 Model 708A switching system card configuration worksheet ................................................................. 3-19
4 Operation
Table 4-1 Setup data paths ......................................................................................................................................... 4-1
Table 4-2 Power-up, reset, and factory defaults ......................................................................................................... 4-3
Table 4-3 Error conditions .......................................................................................................................................... 4-4
Table 4-4 Slave unit controls, indicators, and connections ........................................................................................ 4-9
Table 4-5 Make/break and break/make operation .................................................................................................... 4-11
5 IEEE-488 Programming
Table 5-1 Sample strings ............................................................................................................................................ 5-2
Table 5-2 Contact assignments ................................................................................................................................... 5-4
Table 5-3 Model 708A interface function codes ........................................................................................................ 5-5
Table 5-4 BASIC IEEE-488 statements ..................................................................................................................... 5-6
Table 5-5 IEEE-488 errors causing ERR LED to illuminate ..................................................................................... 5-7
Table 5-6 Digital input display format ....................................................................................................................... 5-9
Table 5-7 Digital output display format ..................................................................................................................... 5-9
Table 5-8 General bus commands/BASIC statements ............................................................................................. 5-10
Table 5-9 Factory default, power-up, and DCL/SDC conditions ............................................................................. 5-11
Table 5-10 Order of command execution ................................................................................................................... 5-12
Table 5-11 DDC summary ......................................................................................................................................... 5-13
Table 5-12 Master/slave setup example ..................................................................................................................... 5-20
Table 5-13 Byte counts for data format ...................................................................................................................... 5-21
Table 5-14 Typical transmission and hold-off times – stand-alone ........................................................................... 5-41
Table 5-15 Typical transmission and hold-off times – master and one slave ............................................................ 5-42
List of Tables
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xii
6 Principles of Operation
Table 6-1 Display segment assignments .................................................................................................................. 6-10
7 Maintenance
Table 7-1 Recommended troubleshooting equipment ............................................................................................... 7-8
Table 7-2 Power supply checks .................................................................................................................................. 7-9
Table 7-3 Microcomputer checks ............................................................................................................................... 7-9
Table 7-4 Relay control checks ................................................................................................................................ 7-10
Table 7-5 Display interface checks .......................................................................................................................... 7-10
Table 7-6 Digital I/O checks .................................................................................................................................... 7-10
Table 7-7 Light pen checks ...................................................................................................................................... 7-11
Table 7-8 Master/slave checks ................................................................................................................................. 7-11
Table 7-9 Display board checks ............................................................................................................................... 7-13
8 Replaceable Parts
Table 8-1 Model 708A mother board, parts list ......................................................................................................... 8-2
Table 8-2 Model 708A front panel control board, parts list ...................................................................................... 8-4
Table 8-3 Model 708A backplane board, parts list .................................................................................................... 8-4
Table 8-4 Model 708A display board, parts list ......................................................................................................... 8-5
Table 8-5 Model 708A miscellaneous, parts list ........................................................................................................ 8-5
C IEEE-488 Bus Overview
Table C-1 IEEE-488 bus command summary ............................................................................................................ C-4
Table C-2 Hexadecimal and decimal command codes ............................................................................................... C-5
Table C-3 Typical addressed command sequence ...................................................................................................... C-7
Table C-4 Typical addressed command sequence ...................................................................................................... C-7
Table C-5 IEEE command groups .............................................................................................................................. C-7
Table C-6 Model 708A interface function codes ........................................................................................................ C-8
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1
General Information
1-1
1.1 Introduction
This section contains general information about the Model
708A Switching System. The Model 708A is designed as a
programmable switch for connecting signal paths in a matrix
topology. It is for applications requiring a small-scale matrix
(up to 96 crosspoints per mainframe and 480 crosspoints per
master/slave configuration). Plug-in cards are available for
general and special purpose switching applications.
1.2 Features
Key features of the Model 708A Switching System are:
• The switching system accepts one 7X7X switching card
(front or rear panel installation).
• Digital I/O contained in the switching system (sixteen
inputs and outputs with internal pull-up resistors).
• IEEE-488 bus or interactive programming.
• Storage of 100 sets of relay setups, which can be up-
loaded or downloaded through the IEEE-488 interface.
• An active front panel LED display shows the present re-
lay status, a stored setup, or an editing scratchpad.
• High-speed triggering of stored setups.
• Make/break and break/make switching programmable
matrix by rows. Operation is transparent and indepen-
dent of the relay setup.
• Maximum matrix size of 8 rows by 60 columns (480
crosspoints on one IEEE-488 address with five units
connected in a master/slave configuration).
• Sealed construction, low heat producing design elimi-
nates vent holes, which is suitable for cleanrooms.
• An optional light pen is available for interactive control
of relays and editing stored relay setups.
1.3 Warranty information
Warranty information is located at the front of this manual.
Should your Model 708A require warranty service, contact
your Keithley representative or an authorized repair facility
in your area for further information.
1.4 Manual addenda
Any improvements or changes concerning the switching sys-
tem or manual will be explained in an addendum. Be sure to
note these changes and incorporate them into the manual be-
fore using or servicing the unit.
1.5 Safety symbols and terms
The following symbols and terms may be found on an instru-
ment or used in this manual.
The symbol on an instrument indicates that the user
should refer to the operating instructions located in the in-
struction manual.
The symbol on an instrument shows that high voltage
may be present on the terminal(s). Use standard safety pre-
cautions to avoid personal contact with these voltages.
The WARNING heading used in this manual explains dan-
gers that might result in personal injury or death. Always
read the associated information very carefully before per-
forming the indicated procedure.
The CAUTION heading used in this manual explains haz-
ards that could damage the instrument. Such damage may in-
validate the warranty.
!
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General Information
1-2
1.6 Specifications
Model 708A specifications are located at the front of this
manual. These specifications are exclusive of matrix card
specifications, which are located in their appropriate instruc-
tion manual.
1.7 Unpacking and inspection
1.7.1 Inspection for damage
Upon receiving the Model 708A, carefully unpack the unit
and inspect it for any obvious signs of physical damage. Re-
port any damage to the shipping agent immediately. Save the
original packing carton for possible future shipment. If in-
stalling a matrix card at this time, be sure to follow the addi-
tional handling precautions explained in the appropriate
matrix card instruction manual.
1.7.2 Shipment contents
The following items are included with every Model 708A or-
der:
• Model 708A Switching System.
• Model 708A Instruction Manual.
• Fixed rack mount kit (includes mounting hardware).
• Removable feet (for bench-top use — includes hard-
ware).
• Additional accessories as ordered.
1.8 Repacking for shipment
Should it become necessary to return the Model 708A for re-
pair, carefully pack the unit in its original packing carton or
the equivalent, and perform the following:
• Call the Repair Department at 1-800-552-1115 for a
Repair Authorization (RMA) number.
• Advise as to the warranty status of the switching sys-
tem.
• Write ATTENTION REPAIR DEPARTMENT and the
RMA number on the shipping label.
• Fill out and include the service form located at the back
of this manual.
1.9 Optional accessories
The following accessories are available for the Model 708A.
Adapter and switching matrix cards
Model 7070 Universal Adapter Card — The Model 7070
card installs in the Model 708A and is jumper-selectable for
use either as a backplane extender or a breadboard. It has
quick-disconnect screw terminals and 10ft. ribbon cables.
Model 7071 General Purpose Matrix Card — The Model
7071 card has 8 rows by 12 columns of three-pole Form A
switching for general purpose applications. It has mass ter-
minated connectors in addition to quick-disconnect screw
terminals.
Model 7071-4 Dual 4 × 12 General Purpose Matrix Card
— The Model 7071-4 card has two banks of four signal paths
of three-pole switching. Row and column connections to the
matrix are through 38-pin mass terminated connectors.
Model 7072 Semiconductor Matrix Card — The Model
7072 card has 2 rows by 12 columns of two-pole FormA for
low current switching, 4 rows by 12 columns of two-pole
FormA for general purpose switching, and 2 rows by 12 col-
umns of one-pole FormA for C-V switching. It has three-lug
triaxial connectors.
Model 7072-HV High Voltage Matrix Card — The Model
7072-HV switches low level, high voltage, and high imped-
ance signals for semiconductor parametric tests. It has two
low current paths, four general purpose paths, and two C-V
paths. Connections to the matrix are through triax connec-
tors.
Model 7073 Coaxial Matrix Card — The Model 7073 card
has 8 rows by 12 columns of one-pole FormA switching (up
to 30MHz) for applications with single-ended instruments. It
has BNC connectors.
Model 7074-D Eight 1 × 12 General Purpose Multiplexer
Card — This card has eight banks of one signal path of
three-pole switching. Bank connections are through four 75-
pin mass terminated connectors; row connections are
through one 38-pin mass terminated connector.
Model 7075 Eight 1 × 12 Two-Pole Multiplexer Card —
The Model 7075 is a general purpose multiplex switching
card that consists of eight banks of independent 1 × 12 mul-
tiplexer switching. Eight 25-pin D connectors are provided
for bank connections and one for row connections.
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