HP 98640A Installation and operating manual

HP Computer Systems
HP 98640A
7-Channel Analog Input Interface
Hardware
Installation and Reference Manual
FIIOW HEWLETT
~~ PACKARD

HP Computer Systems
HP 98640A
7 -Channel Analog Input Interface
Hardware
Installation
and Reference Manual
r!J~ HEWLETT
a!1!II PACKARD

Fli .. HEWLETT
~I!.II PACKARD
Warranty Statement
Hewlett-Packard products are warranted against defects
in
materials and workmanship. For Hewlett-Packard Desktop
Computer Division products sold
in the U.S.A. and Canada,
this warranty applies for ninety (90) days from the date of
delivery.* Hewlett-Packard will, at its option, repair or replace
equipment which proves to be defective during the warranty
period. This warranty includes labor, parts, and surface
travel costs, if any. Equipment returned to Hewlett-Packard
for repair must be shipped freight prepaid. Repairs
necessitated by misuse of the equipment, or by hardware,
software, or interfacing not provided by Hewlett-Packard are
not covered by this warranty.
HP warrants that its software and firmware designated by HP
for use with a CPU will execute its programming instructions
when properly installed
on that CPU. HP does not warrant
that the operation of the
CPU, software, or firmware will be
uninterrupted or error free.
NO OTHER WARRANTY IS EXPRESSED OR IMPLIED,
INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES
OF MERCHANTIBILITY AND FITNESS FOR
A PARTICULAR PURPOSE. HEWLETI-PACKARD SHALL
NOT BE LIABLE FOR CONSEQUENTIAL DAMAGES.
*For other countries, contact your local Sales and Service
Office to determine warranty terms.

~ .. HEWLETT
a:~ PACKARD
ATTENTION:
Users of Series 300 Computer Systems
Please read this notice berore installing card.
The HP 98640A has one application which may pose serious usage problems:
In Series 300 machines, the right angle posts which connect the ADC
card to its Wire Termination
Assembly can short out on the RFI suppression shield of the processor or other card if the cards are in
adjacent slots. Since
the HP 98640A must be installed in the lower of paired slots, this occurance is likely.
There are two possible solutions.
The recommended solution is to apply an insulating material (such as electricial tape) to the upper surface
of the RFI shield on the processor or other card.
The second, while more difficult. is equally effective: Always place the ADC card in a slot where the
contacts are cl4early not touching any conductor. This is not always possible due to the installation
constraint mentioned above.

HP 98640A
7-CHANNEL
ANALOG INPUT INTERFACE
FOR HP 9000 SERIES 200 COMPUTERS
HARDWARE INSTALLATION AND
REFERENCE MANUAL
Fliii. HEWLETT
~~ PACKARD
Card Assembly: 98640-66501
Date Codes: A-2.419
B-2.420
HEWLETT-]PACKARD COMPANY
Roseville Networks Division
ManuaIPartN~98640-90001
E0784
Printed in U.S.A
July 1984
8000 Foothills Boulevard
Roseville, Callifornia
95678

[ PRINTING HISTORY
The Printing History below identifies the Edition of this Manual and any Updates that are
included. Periodically, update packages are distributed which contain replacement pages to
be merged into the manual, including an updated copy of this Printing History page. Also,
the update may contain write-in instructions.
Each reprinting of this manual will incorporate all past updates; however, no new informa-
tion will be added. Thus, the reprinted copy will be identical in content to prior printings
of the same edition with its user-inserted update information. New editions
of this
manual will contain new information,
as well as updates.
FIRST EDITION ...................................................................... July 1984
NOTICE
The information contained in this document is subject to change without notice.
HEWLETT-PACKARD MAKES NO WARRANTY OF ANY KIND WITH REGARD TO
THIS MATERIAL, INCLUDING, BUT NOT LIMITED
TO, THE IMPLIED WARRANTIES
OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
Hewlett-Packard shall not be liable for errors contained herein or for incidental or con-
sequential damages in connection with the furnishing, performance, or use of this material.
This document contains proprietary information which
is protected by copyright. All
rights
are reserved. No part of this document may be photocopied or reproduced without
the prior
written consent of Hewlett-Packard Company.
Copyright (c) 1984 by HEWLETT-PACKARD COMPANY
ii

98640A Analog Input Interface
CONTENTS
Content!l ...••.........•....................•..............•...........•... iii
Preface .................................................................... vi
General Safety Con5ideration5 ..
GENERAL ]tNFORMATION
Overview .•••••
Description ••.
Standard Product ..•
Options .•••...
Identification ..
Specification5 ... .
Electrical ... .
Functional Specifications ..
Cont",'ol .••.................
INSTALLATION
Unpacking and Inspection ...
Caut!lons ..•.
In5pect contents.
Preparation for use ...
Calculating power requirement5 ..
Component installation ..
Boot-up ID number.
Switch Set~in9s .....
Factory Settings.
Interrupt Level ..
Inserting the card.
Where ..
How ....
Removal ..
Checking a new A-to-D card.
Attaching the wire termination aS5embly.
Cabli
nB. . . . . . . . ...•.
Wi re ....... .
Connection
..
Removal .....
Operational Con5iderations.
Return Shipment ••..........
THEORY OF OPERATION
Power and Timing.
Powelr Supply .•
System Clock .••.••.•.•.•.
iii
• vi i
• •1-1
1-1
.1-2
1-2
· . 1-2
· . 1-3
· 1-3
· 1-3
• 1-4
.2-1
· .2-1
.2-1
· .2-2
· .2-2
· .2-2
· .2-2
· .2-2
· .2-4
· .2-4
..2-5
· .2-5
· .2-5
· .2-6
· .2-7
.2-7
· .2-8
..2-8
.2-8
.2-11
.2-12
.2-13
....... . 3-3
· .3-3
.3-3

98640A Analog Input Interface
Registers ................................................................. 3-3
])ata Registers .•.•...•....................•..•.......••...••••••.••.•••• 3-3
Pace Timi ng Regi ster •••..•••.....•..••.•.•.•.••...••.....•••.•..•••••••• 3-4
ID Regi ster ....•.•..................•................................... 3-4
Status Regi ster ..••...•......................•..............•...•....... 3-4
Analog Circui try ••.....•..............•.................•...•.........••.. 3-5
Vol tage Input ..•.•...•.•....•..........••.................•.•.•...•.•••. 3-5
Channe1 Se 1 ec t ion .•......•...••..• L' •••••••••••••••••••••••••••••••••••• 3-6
Prograrrrnable Gai n Ampl i f ier (PGA) ..••..•••••••.....•......•..•••••...... 3-7
Gain of 1 ............................................................. 3-7
Other Gains .••.•...•...•....•....••...•.•.••.....•.•...••..•.••••...•. 3-9
Examp 1e ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 3-9
Di fferent ial-to-Si ngle-Ended Converter ...•..•.....•....•.••..•.•..•.••. 3-1 0
Example •••••••••••••••••••••.•.••••••••••••••.••••••••••••••••••••• 3-10
Sample and Hold (StH) Circuit •.......•.••••..••••....•••.••.••.•.•..••. 3-10
Absolute Value Circuit .•••..••........••..••.•.......••..•..••••..•..•• 3-11
Analog-to-Digi tal Converter (ADC) ......•....•.•.•....••..•.••..•.•...•. 3-12
Corrmon Mode Over range Detect ion ........•......•.......••.••.••....•.... 3-13
Digital Conversion Circuitry ...••..••...••.••....•......•..•••••.•....•.. 3-13
Generating Control Signals .........•.•.•.•••.•....••.••.•••.•••.•.....• 3-13
Stopping the Counter .••.••••.....•....••..••••••...•.•••..•.•••.•...... 3-14
Conversion Cycle Timing .....•....••.•..•....••.....•.••...•.••...••.... 3-17
The BUSY eye Ie ......................................................... 3-18
The Internal Pacing Timer •...••....•••.••••••••••.••..•.•••.•.•...•..•• 3-19
External Pacing ..•...............•........•........•..•................ 3-20
Digi tal Backplane Circui try ..•.•...••....••••.••••.....•.•....••...•..••. 3-20
Select Code ••.••••.........•••...•...••••••....•...••.••.....•....••.•. 3-20
The Backplane Handshake ••..•••...•••...•.....•••••..........•••...•..•. 3-21
Addressing .•...•.•.•..•..•..•.•...•.••...••..•.....•..•..••.•••...•.•.. 3-21
Reset!! .........•..•..•.................•.....•......................... 3-22
Backplane Data Bus ...••..•.•....••........•.••....•••••...•.••....•..... 3-22
Reading From the Card ..•...•........•..•..••••....••.........•...•..... 3-22
Wri ting to the Card .•••..•.......••.••••..•..•.•...•.••...•.•••...•..•. 3-22
Interrupt5 .•.....•........................•............................ 3-23
Sequence of Operations .....•...•....•••.....•..............••.•.•..••.••. 3-23
The Analog Pipeline •...•.....•••.•...••..•.••..•.•.........•..••.•..•.... 3-25
PROGRAMMING AND EXTERNAL PACING
Programning Considerations .•.....•.......•....••........•...•.••.•..•.•.•. 4-1
Channel and Gain ...•.•.....•.....•..•.....•..•••............•.....•.•... 4-1
Dealing wi th Data •••.•.•....•.••..•....•.....•............•....••.....•. 4-3
Calibration .•••••..•••.....••......•....•...••.........••....•..•..... 4-3
Detailed Calibration ...............•..............•..••....•........ 4-4
Qu i c k Ca lib rat ion. . • . . . • . . . . . . . . • . . • . . •. . . . . . . . . . . • • . . . • . . . • . . . . . . • . 4- 5
Over range!! ..••.••......•...•••....••......•••.......•.•.•.••.•••..••.. 4-7
Horrra1 mode •••••••••••••••••.•••••••••••••••.••••.•••••••••••••••••• 4-7
COlll'non mode •.•...•.....•..•........•..•....•..........•...••.•••..•. 4- 7
Simple sample •••.•.•.•.•.....•............••.•......•...••••••..•.•... 4-7
Pace Interval ..•..........................•....•...•........•....••..... 4-9
No i Sf!! •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 4-1 0
iv

98640A Analog Input Interface
External Paci"9 .......................................................... 4-10
Control Line5 .......................................................... 4-11
Appl iClat ion5 ........................................................... 4-11
Note on :8ASIC Syntax ..••.•••••••••..••...•.•..•.•.•.....•.•..•....•...••. 4-13
MAINTENANCE
Ove rv i ew. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
Preparing to test the A-TO-D card .....••........•.••••.••.•..•••••••••••.• 5-1
Mi nimunl equipment requi rement s •••..•.....•.....••..•••.•••••.•.•.•••..•• 5-1
Installing test assembly ..•.••..•••...•........•..•.....•.•.•...•..••.•. 5-1
Di5c
1
onnecting the WT'A .........•.......•.........•.••.....•.•..•....... 5-1
I nstiall Peripherals ..•••..••...•••........•..•..•..••.•..•.••••••••... 5-2
Connecting the test assembly ..••.•.•••...•.....•...........••.•.•..... 5-2
Verification Test .........••.....••.•...•..•......•..............•........ 5-3
Ove rvi lew. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5- 3
Loading the verification program .•..•.•....•..••.•.•..•.......•....•.•.. 5-3
Sequ1ence .............................................................. 5- 3
Test~5 Performed .....................................•.........•....... 5-4
Prograrn run ............................................................. 5-4
I nsti~ lIed ADCs ....•....................•...•..........•............... 5-4
Set I~epet i t ions ...........................•................•..•....... 5-4
Pace Timer Test .•.......•.................•.........•..•.....•.......• 5-4
Select Readings to Display .............•.....•...•••..•..•....•....... 5-4
Run-Error Reporting .............................•................•.... 5-5
Succes~5ful Verification ...........•.........•..•..•..•........•.•....... 5-5
On Failure •••..........•.....•....••.......•...•........................ 5-5
Error' Codes ....................•..........•.....•..................... 5-6
PARTS LISTS
Organization ......................................................•....... 6-1
Ava i lab i .1 i t y .............................................................. 6-1
A-to-D card •.•.......................................................... 6-2
wire tl~rmination assembly ................•......•...•................... 6-5
test a!5sembly ...•...............................•.......•..•............ 6-6
DIAGRAMS
Resistor network ......................•....•.....•..•....•........•....... 7-2
Component Location
A-to-D card and wire term. assy ..........•..•.........•....•............ 7-3
T est a !5 s emb Iy. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7- 4
Schematic: diagrams
A-to-D card .........................................................•... 7-5
wi ret I:! rm. as sy ........................................................ 7-11
t est a!5 s emb I y. . . . . • . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ......•.•..•........... 7-1 2
PROM code .................................................•............ 7-13
INADVERTANT GROUND: A SAFETY CONSIDERATION ............••..........••..•..•. A-1
Glossary .......................................................•............ G-1
INDEX
v

98640A Analog Input Interface
PREFACE
The HP 98640A Analog Interface is designed to make putting an HP 9000 Series 200 computer in
touch with the IIreal world
ll
easy. In this manual we explain how to install the interface in your com-
puter. We also present a very simple example of an assembly language program for making a single
reading from
an input. This example, in section four, is aimed at advanced assembly language
programmers.
This manual's Appendix briefly explains how
the HP 98640A Analog Input Interface may affect an
existing application. A glossary follows the Appendix. Also in the back are two different reader
comment forms. One form asks you to evaluate this manual,
the other asks what follow-on products
you may have a
future need for.
One product that is already available is the HP 98645A Measurement Library. The library's set of
subroutines that you can call from high level languages may save considerable development time. The
following languages can call routines from
the library:
BASIC 3.0 and 2.0 with
2.1 extensions
Pascal 3.0, 2.1, and 2.0
Contact your Hewlett-Packard sales representative for more information about the HP 98645A
Measurement Library.
We strongly recommend the following books to anyone who intends to write his or her own assembly-
language application programs
for 9000 Series 200 computers:
·Pascal 2.0 System Designer's Guide, part number 09826-90074
·MC68000 User's Manual, part number 09826-90073
If you are interested in producing applications software, ask your Hewlett-Packard representative
about HP+. We can help you get
the word out about your application.
vi

SAFETY CONSIDERATIONS I
GENERAL - This product and relation documentation must be
reviewed for familiarization with safety markings and instruc-
tions before operation,
CAUTION
SAfETY SYMBOLS
Instruction manual symbol: the product
will be
marked with this symbol when it is
necessary for the user to refer to' the i n-
struction manual in order to protect the
product against damage,
Indlcatt.·s hazardous \'oltages,
Indicatt.·s
t'arth 'groundl terminal Isome-
tmlt.'s lIsed
in manual to indicate circuit
('OmnlOn connt.·cted to grounded chassisl,
The WARNING sign denotes a hazard.
It calls attention to a procedure. prac-
tice. or the like. which. if not correctly
performed or adhered to. could result
in injury. Do not proceed beyond a
WA RNING sign until the indicated
conditions are fully understood and
met.
The ('A l"rI()!\; sign d('not('s a hazard It
calls attt.·ntion to an opt'r"ting pron·dure.
practin·. or tht.·like. which.
ifnot cOITectl.\'
pl'ri'ol'llwd or adht'red to. could result in
damagt.· to or dt.·structlon of part or all of
tht.· pl'Oduct. Do not proceed heyond a
CA l'TION sign until the Indicated ·condi-
tions
are full~' undt.·rstood and met.
CAUTION
STATIC SENSITIVE DEVICES
When any two materials make contact, their surfaces
are crushed on
the atomic level and electrons pass
back
and forth between the objects, On separation,
one surface
comElS away with excess electrons (nega-
tively charged) while the other is electron deficient
(positively
chargt~d). The level of charge that is devel-
oped depends upon
the type of material. Insulators
can easily build
up static charges in excess of 20,000
volts. A person working at a bench or walking across a
vii
floor can build up a charge of many thousands of
volts.
The amount of static voltage developed de-
pends on the rate of generation of the charge and the
capacitance of the body holding the charge. If the
discharge happens to go through a semiconductor
device
and the transient current pulse is not effective-
ly diverted by protection circuitry, the resulting cur-
rent flow through the device can raise the tempera-
ture of internal junctions to their melting points.
MOS structures are also susceptible to dielectric
damage
due to high fields. The resulting damage can
range from
complete destruction to latent degrada-
tion. Small geometry semiconductor devices are espe-
cially susceptible to damage by static discharge.
The basic concept of static protection for electronic
components
is the prevention of static build-up where
possible
and the quick removal of already existing
charges.
The means by which these charges are re-
moved
depend on whether the charged object is a
conductor or
an insulator. If the charged object is a
conductor such as a metal
tray or a person's body,
grounding
it will dissipate the charge. However, if the
item to be discharged is an insulator such as a plastic
box/tray or a person's clothing, ionized air
must be
used.
Effective anti-static systems must offer start-to-
finish protection for the products that are intended
to be protected. This means protection during initial
production,
in-plant transfer, packaging, shipment,
unpacking and ultimate use. Methods and materials
are in use today
that provide this type of protection.
The following procedures are recommended:
1. All semiconductor devices should be kept in "antis-
tatic" plastic carriers. Made of transparent plastics
coated with a special "antistatic" material which
might wear off with excessive use, these inexpen-
sive carriers are designed for
short term service
and should be discarded after a period of usage.
They should be checked periodically to see if they
hold a static charge greater than 500 volts in
which case they are rejected or recoated, A 3M
Model 703 static meter or equivalent can be used
to measure static voltage, and if needed, carriers
(and
other non-conductive surfaces) can be recoat-
ed with "Staticide" (from Analytical Chemical
Laboratory
of Elk Grove Village, Ill.) to make them
"antistatic."
2. Antistatic carriers holding finished devices are
stored in
transparent static shielding bags made by
3M Company. Made of a special three-layer mate-
rial (nickle/polyester/polyethylene) that is "antis-
tatic" inside
and highly conductive outside, they
provide a
Faraday cage-like shielding which pro-
tects devices inside. "Antistatic" carriers which
contain semiconductor devices should be kept
in
these shielding bags during storage or in transit.

Individual devices should only be handled in a
static safeguarded work
station.
:3. A typical static safeguarded work station is shown
below including grounded conductive
table top,
wrist
strap, and floor mat to discharge conductors
as well as ionized
air blowers to remove charge
from nonconductors (clothes). Chairs should be
metallic or
made of conductive materials with a
grounding
strap or conductive rollers.
SAFETY EARTH GROUND - This is a safety class I product
and is provided with a protl,('ti\'t' l'arthin~ terminal. An uninter-
ruptihle safet~· l'arth ground must Ix- provided from the main
power sourn' to tht, produ(·t input wirin~ terminals, power cord.
or supplied pOWt'r cord set. Wht'fl('\'t'r it is likeiy that tht' protec-
tion has Ix-t'n impairt'd. thl' product must be madt' inoperative
and nt, ,.;t'(·un·d against an~' unintl'ndt'd operation.
BEFORE APPLYING POWER. - \'erif~' that the product is
(:onfiJ,.rurt'd to match thl' a\'ailahll' main power source per tht'
input powt'r confj~urati()n in"tructions provided in this manual.
If this product is til hI' l'lll'rl-:ll.l'd \1;\ an auto-transf()rmer tfor
\"oltClgt' n,duction I milk!' sun' tIll' wmmon tl'rminal is connected
til tht, l',II1h (t'rminal
of tht, Illalll powt'r SCHliTt'.
SERVICING
viii
Any servicing. adjustment. maintenance. or re-
pair of this product must be performed only by
qualified personnel.
Adjustments described in this manual may be
performed with power supplied to the product
while protective covt'rs are removed. Energy
available at many points may. if contacted. re-
sult in personal injury.
Capacitors inside this product may still be
charged even when disconnected from its
power source.
To avoid a fire hazard. only fuses with the re-
quired current rating and of the specified type
(normal blow. time delay. etc.) are to be used for
replacement.
'iU·';U"hi
EYE HAZARD
Eye protection must be worn when removing or
inserting integrated circuits held in place with
retaining clips.

GENERAL INFORMATION IF'!'H',
OVERVIEW
The HP 98640A 7-channel Analog Input Interface is an analog-to-digital converter (ADC) for
Hewlett~Packard 9000 Series 200 computers. On each HP 98640A 8 analog channels are available
for measuring small differential voltages
with 13-bits resolution (including sign-bit). We call the HP
98640A a 117 -channel" interface because in applications where an input offset voltage is less tolerable
the two leads
of one channel may be shorted together and grounded. The reading from the shorted
channel serves as a reference you can use
to correct readings made on the other channels.
The HP
98640A can sample its inputs in any order. You can control the amount of time between
readings by programmatically setting
the interface's pace timer. The interface will then do the pacing
automatically.
It can send an interrupt to the computer when a sample h'as been taken. Even the
voltage range for a channel can be changed between samples. The maximum voltage for inputs is plus
or minus 10 volts. The minimum full-scale voltage range is plus or minus 19.5 millivolts. The maxi-
mum differential voltage measurable is plus or minus 9.99756 volts (best case) at a gain of 1 (full scale
voltage minus one least significant bit
(Isb) value).
The interface's
four input voltage ranges will accommodate signal sources ranging from control cir-
cuits to thermocouples. The voltage ranges are determined by the amplification of the input voltage
by
the card. Y--ou can select any of 4 gains for any channel. The four gain factors are 1, 8, 64, and
512. This allows the ADC integrated circuit (IC) on the card to always see a voltage between 0 and 10
volts.
The rest of this section describes
the interface and includes the operational specifications.
DESCRIPTION
The HP 98640A is actually two printed circuit assemblies (PCA). The main PCA is the A-to-D card
which includes the analog-to-digital converter, programmable gain amplifier (PGA), pace timer, and
backplane interface circuitry. Unlike most interface cards for 9000 Series 200 computers, the cover
plate
is not attached to the main card. Instead, the plate is is attached to the second PCA.
The second peA plus the attached cover plate is called the wire termination assembly (WTA). On this
PCA are the wire termination blocks, input protection circuitry, and the control inputs for external
pacing. The wire
termination blocks accept individual solid hook -up wires up to 18 gauge. Each wire
is clamped in a termination block's receptacle by turning a setscrew. The cover plate attached to the
PCA has two captive thumbscrews (dog bolts) to secure the entire assembly to the back of the com-
puter. The main PCA should never be operated unless a WTA or test assembly is attached.
1-1

98640A Analog Input Interface
NOTE
Additional wire termination assemblies may be ordered.
By using several assemblies you can readily switch be-
tween several predetermined wiring arrangements. The
assembly's
part number is 98640-66502. Contact your
HP representative or Hewlett-Packard's Corporate Parts
Center (CPC) to place an order.
Also on
the wire termination assembly are 9 termination receptacles tied to chassis ground and one
receptacle tied to a low
current (less than Sarna) +5 volt source, for use with the external control in-
puts. THIS +5 VOLT SOURCE IS NOT INTENDED FOR USE AS A POWER SUPPLY. The ter-
mination receptacles are listed in Section II.
STANDARD PRODUCT
When the HP 98640A was ordered one of three options had to be specified. The option specified
determines
what equipment you received. When you unpack the cards you may want to refer to the
following lists:
Options
Standard Product
• A-to-D card, part number 98640-66501
• Wire termination assembly (WTA), part number 98640-66502
• Test assembly, part number 98640-67950
• This installation manual, part number 98640-90001
• Verification option (only one may be selected)
VERIFICA
TION OPTIONS
001 -Deletes test assembly
630 -Adds verification software on 3.5 inch disk, part number 98640-13301
655 -Adds verification software on 5.25 inch disk, part number 98640-13601
IDENTIFICATION
Five digits and a letter (98640A) identify the Analog Input Interface. As with most Hewlett-Packard
products used with 9000 computers these five digits identify the product. The letter suffix represents
the revision level of the product.
The main printed
circuit assembly or PCA (printed circuit board with all components in place) is
identified
by a part number (also called a card assembly number) followed by a date code. On the
1-2

98640A Analog Input Interface
A-to-D card the part number is on the component side near the right-angle posts. The part number is
98640-66501. The line of characters below the part number is called the date code. It identifies the
circuit (by letter) and electrical characteristics (the four-digit encoded date). If there is a suffix (typi-
cally a lower-case letter») it identifies additional revisions to the PCA.
If the date code on the A-to-D card does not correspond to the date code printed on the title page of
this manual) there are differences between the interface described in this manual and the Analog
Input Interfa.ce you have received. Contact your nearest Hewlett-Packard Sales and Service office
(listed
at the back of this manual) for manual update information.
SPECIFI<:A TIONS
ElectricaJ
Power Requiirements:
.672W (@ +12V)
.228W (@ -12V)
+ 2.570W
(@ +5V)
3.5 Watts total
Input overvolltage protection: Transorbs redirect voltage in excess of ± 15 volts to ground.
Input resistance, each channel: 1 OOmegohms (power on)
WARNING
Each input is routed through a 1k (one thousand) ohm
resistor
to ground when the power is off ..
Functional Specifications
On-board clock: 1.667Mhz
Resolution
of Internally clocked Pace rate: 600 nanoseconds
Sample and hold aperture time: 25 nanoseconds
Time from first Read to Hold at 55k samples/second: 7 microseconds
Minimum sample cycle: 18usec.
Linearity:
0.02% of full scale
Temperature coefficient for voltage offset: 10 microvolts per degree centigrade.
Common-mo.le rejection
ratio (CMRR): 90db @ 60hz
1-3

98640A Analog Input Interface
Input voltage ranges: These ranges only specify the voltages acceptable
at a particular gain. The
differential voltage between a channel's inputs should not equal or exeed full scale
(see below).
1 1
GAIN 1 INPUT VOLTAGE RANGE 1
------------1-----------------------1
1 1
1 1 + to - 10V 1
1 1
8 1 + to -1.25V 1
1 1
64 1 + to - 156mV 1
1 1
512 1 + to -19.5mv 1
Other sampling characteristics are listed in table 1 -1.
Control
Minimum external trigger pulse width: 2.3 microseconds
Trigger voltage: +2 to +50volts (trigger voltage must not
go below ground)
1-4

GAIN
FULL SCALE
LSB
RMS NOISE*
STD DEVIATION
OFFSET AFTER
CALIBRATION
(WORST CASE)**
ACCURACY AFTER
CALIBRATION
(WORST CASE)**
INPUT
AMPLIFIER
SLEW RATE
MAX. SAMPLE
RATE (ACHOSS
CHANNELS)
MAX. SAMPLE
RATE (ON A
SINGLE CHANNEL)
98640A Analog Input Interface
Table 1-1
SAMPLING CHARACTERISTICS
1 8 64 512
±10V
±1.25V ±156mV
±19.5mV
2. 44mV
305uV 38.1UV 4. 77uV
5mV
600uv
lOOUV 18uv
±7.3mV
±915uV
±152UV
±24uv
±18mV
±3mV ±250uV ±75uV
400mV/usec 50mV/usec 4mV/usec 40uV/usec
20k/sec 20k/sec
14k/sec
lk/sec
55k/sec 55k/sec
55k/sec
55k/sec
* By averaging readings noise can be reduced to less than one least significant bit (Isb).
** These figures are based on an HP 98640A whose data were processed and controlled
by routines from the HP 98645A Measurement Library. The accuracy figures show
the worst case affects of noise after the library's noise reduction routine is used.
1-5

INSTALLATION -
"- ________ ----r[[]
UNPACKING AND INSPECTION
The procedures for unpacking this interface are described below. Please follow these procedures to
preserve your rights under the laws governing freight shipments
and to protect the hardware. You
will find these procedures in many Hewlett-Packard hardware manuals.
Look for obvious signs
of damage to the package. If the outside of the box is damaged or has water
stains, or the box rattles, contact the carrier. Ask that a carrier's agent be present when you open the
box. If there is no obvious reason to have the carrier's agent present read the cautions below and on
the box before proceeding.
Cautions
Please read "Safety Considerations" at the front of this manual, especially the portion dealing with
static electricity.
CAUTION
The A-to-D card (see figure 2-2 for an outline drawing
of this card) contains static sensitive devices. Use anti-
static handling procedures when working with it.
When you re:move the A
-to-D card from its packing material handle it by the edges or the plastic
levers (extractors)
in the corners next to the right-angle posts. Do not touch the gold-plated contacts
at the end of the card opposite the right-angle posts. If you do get a fingerprint on the gold-plated
contacts or
the right-angle posts, clean them with a lintless tissue moistened with a small amount of
isopropyl alcohol.
CAUTION
Never clean the contacts or the right-angle posts with
an abrasive cleaner such as an eraser because the plating
may be damaged.
Inspect c:ontents
Check the contents of the package to verify that you have received the product and options you or-
dered. Refer to the description of the Standard Product and options in Section I, and your invoice. If
any parts appear to be missing, notify your Hewlett-Packard Sales and Service office.
Inspect
the contents carefully for hidden damage such as detached components, corrosion, or cracks
and dents. Notify
the carrier who delivered this product and your Hewlett-Packard Sales and Service
office
if you find any damage. Save the packing material for the carrier. A representative at our
Sales and Service office. will arrange for repair or replacement without waiting for the settlement of
the claim against the carrier.
2-1

98640A Analog Input Interface
PREPARATION FOR USE
Calculating
power requirements
Check your computer system manual to find how much power (in watts) is available from the com-
puter's power supply at each voltage the supply provides. Add the power requirements at each voltage
for all of the cards you already have
in the computer. Then add the power requirements of each
A -to-D card you will install to the totals.
If the power required at any voltage is greater than the power supply's rating at that voltage, you
must make some adjustment to your computer. Either reconfigure your system by omitting unneces-
sary cards or arrange to buy bus expanders through your Hewlett-Packard Sales and Service office.
Component Installation
There are no loose components to install on the A -to-D card or the wire termination assembly.
Boot-up 10 number
The 10 number of the card is a feature required by the operating system. The 10 register on the card
is hardwired to respond, "18", when polled during system boot-up. The operating system also checks
the address (which
we will explain how to set below) of the A -to-O card. The 10 number and address
are used by the operating system to associate the card with an application program.
SWITCH SETTINGS
The A-to-D card has a DIP (dual in-line package) block of switches (SWl) located as shown in figure
2
-1. Switch numbers are on the switch block. These switches control the card's address and the
priority level of any interrupt the card transmits. You must select part of the address for the card.
The portion of
the address you set on switches 1 to 5 is called the select code. The remainder of the
address is already hardwired.
If you use a program which requires the card to send a specific level
hardware
interrupt to the system, you must set the interrupt level the card will send before you install
the card in the computer. Figure 2-1 shows the switches set as they are when the A-to-O card leaves
the factory;
the select code is 18 and interrupt level is 3.
The logical state of any switch corresponds to the numbers 0 and 1 silked-screened on the card just to
the right of the block of switches (SW 1). To set a specific select code or interrupt level just set the
switches to the logical states shown in Table 2- 2. When a switch is closed, the bit it controls is low
(logical zero). When a switch is open, the bit it controls is high (logical one). You can use your finger-
nail or the tip of a ball-point pen to change a switch's setting.
2-2