Agilent Technologies 34970A User manual

Agilent 34970A
Data Acquisition/Switch Unit
Product Overview
Agilent performance
at a fraction of the cost
of other standalone
data acquisition systems

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Table of Contents
Features
Using the 34970A for data logging applications
Data Logging Feature Checklist
Using the 34970A for ATE applications
ATE Feature Checklist
Using the 34970A for switching applications
Customize your 34970A with plug-in modules
Modules-at-a-Glance Selection Guide
Agilent Quality
Spec Interpretation Guide
Accuracy Specifications
System Specifications
Software
Modules Specifications
Multiplexers (34901A, 34902A, and 34908A)
Actuator module (34903A)
Matrix module (34904A)
RF Multiplexer modules (34905A, 34906A)
Multifunction module (34907A)
Rack Mounting and Dimensions
Ordering Information

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Price and performance beyond compare
Go ahead and compare the Agilent Technologies
34970A Data Acquisition/Switch Unit with other
data acquisition systems currently available. You’ll
find it hard to come up with a system that offers
the powerful measurement performance, flexibility,
and ease of use of the 34970A— even in systems
costing three to five times as much.
How did we manage to pack so much performance
into such a low-cost instrument? We borrowed tech-
nology developed for our top-of-the-line products
and put it into a package that cuts assembly time,
incorporates custom ICs to reduce parts count, and
simplifies production testing. That means it costs
us less to make. The results? You spend less with-
out sacrificing quality or performance.
What can you expect from a data acquisition
system that’s this affordable?
Measurements you can trust
We took the measurement engine from our best-
selling benchtop DMM and embedded it inside a
3-slot cardcage. You get the benefit of proven Agilent
measurement performance, universal inputs with
built-in signal conditioning, and modular flexibility,
all in a low-cost, compact data acquisition package.
The 34970A features 61 /2digits (22 bits) of resolution,
0.004% basic dcV accuracy, and ultra-low reading
noise. Combine that with scan rates of up to 250
channels/sec, and you’ve got the speed and accuracy
you need to get the job done right the first time.
Powerful flexibility to get your job done
Whether you need to measure temperature,
ac/dc volts, resistance, frequency, or current, the
34970A can handle it. The internal autoranging
DMM directly measures 11 different functions,
eliminating the need for expensive external signal
conditioning. And our unique design allows com-
plete per-channel configurability for maximum
flexibility and quick, easy set up. It’s like having
an independent, high-performance DMM behind
each channel.
Custom configurations that grow with you
Three module slots and eight switch/control
modules allow you to customize the 34970A to
meet your unique requirements. Buy only what
you need—and add more modules later as your
application grows.
Unequaled ease of use
From the simplified configuration procedures,
to the self-guiding front panel interface, we put
in extra time and energy to save yours. Simple
things like on-module screw-terminal connectors,
built-in thermocouple reference junctions, well-
organized user documentation full of examples
and hints, and a standard Getting Started kit that
will have you making measurements 15 minutes
out of the box all add up to increased productivity,
whether you use the instrument every day or
only now and then.
Free software to save you time and money
Now you don’t have to spend your valuable time
writing or configuring software. Agilent BenchLink
Data Logger II software gives you a familiar
Microsoft Windows® interface for test configura-
tion and real-time data display and analysis. Even
better, the data logging application is included
with every standard Agilent 34970A.

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3-slot mainframe
offers up to 96 matrix crosspoints or
120 single-ended channels
Agilent BenchLink Data Logger II
software included;
drivers available for Agilent VEE and
National Instruments LabVIEW
Intuitive front panel: task-oriented,
self-guiding menus
50k readings of non-volatile
memory holds data when
power is removed
HI/LO alarm limits on each input
channel, plus 4 TTL alarm outputs
Scaling function for
converting raw inputs
into user-defined units
61 /2-digit (22-bit) internal
DMM measures 11 functions without
external signal conditioning
8 switch and control
plug-in modules to
choose from
Battery-backed real-time clock for pacing
scans and timestamping readings
Built-in GPIB and RS-232 interfaces
Monitor display
mode lets you
keep an eye on
tests in progress
More power and flexibility
than you ever imagined you could afford

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The Agilent 34970A offers unequaled versatility
for your data acquisition applications
In the past, you had to make a choice. On the one
hand, you could choose the simple operation and
low cost of a data logger. On the other hand, you
had the flexibility and higher performance of
a modular data acquisition system. The Agilent
34970A Data Acquisition/Switch Unit gives you
the best of both worlds: a simple user interface
with low per-channel cost, modular flexibility,
and impressive measurement performance.
Whether you’re an R&D engineer working on char-
acterizing your latest design, or a manufacturing
engineer building a test system or troubleshooting
a process, the 34970A Data Acquisition/Switch
Unit offers the best combination of price and meas-
urement performance.
It’s a data logger:
Configured with a 20-channel relay multiplexer,
the 34970A becomes a powerful, low-cost data
logger for simple characterization applications—
one that’s quick to set up and easy to run. For
more information on using the 34970A for data
logging applications, see page 6.
It’s a data acquisition front-end:
The 34970A is an automated test system with
excellent measurement performance—it’s got the
accuracy, resolution, and speed you need. See
page 8 for application information.
It’s a switch system:
Order the mainframe without the internal DMM
and you’ve got an even lower cost, high-quality
signal routing solution. See page 10 for details.

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An easy-to-use data logger for monitoring
and characterization applications
Data loggers are used to monitor multiple signals
(temperature, voltage, etc.) over extended periods
of time to identify irregularities. Example applica-
tions include environmental chamber monitoring,
component inspection, benchtop testing, process
troubleshooting, and temperature profiling.
The Agilent 34970A is easy to use for a multitude
of data logging and monitoring applications, either
stand-alone or with a computer. Its flexible, modu-
lar design makes it scalable from 20 to 120 chan-
nels, and lets you add actuator, digital I/O, and
analog output channels for simple control. Its small
size and ruggedized features make it perfect for
portable applications, and its small footprint makes
it ideal for cramped benchtop testing. Standard
GPIB (IEEE 488) and RS-232 interfaces let you pro-
gram the instrument if you wish to automate tests.
Better measurements with fewer hassles
Tired of putting up with the mediocre measure-
ment performance you get with most data loggers
or plug-in data acquisition boards? The 34970A
offers 61 /2digits of resolution and 0.004% basic
1-year dcV accuracy.
Simplify your data gathering with
Agilent BenchLink Data Logger II software
Do you want PC-based data logging capability,
but don’t want to spend hours programming?
The BenchLink Data Logger II software is the
answer. This Windows-based application is
designed to make it a snap to use your PC for
gathering and analyzing measurements. Use
it to set up your test, acquire and archive meas-
urement data, and perform real-time display
and analysis of the incoming measurements.
A familiar spreadsheet environment makes it
easy to configure and control your tests. And
a rich set of colorful graphics provides many
options for analyzing and displaying your data—
all with point-and-click ease. Set up multiple
graphics using strip charts, histograms, bar and
scatter charts, individual channel results, and
more. And of course you can use BenchLink
Data Logger II to easily move data to other
applications for further analysis, or for inclusion
in your presentations and reports.

And the 34970A measures and converts
11 different input signals:
• temperature with thermocouples, RTDs,
and thermistors
• dc and ac volts
• 2- and 4-wire resistance
• frequency and period
• dc and ac current
What’s more, each channel is independently config-
urable. This means you can configure channel 1
for dcV, channel 2 for a K-type thermocouple, and
channels 3 and 13 for a 4-wire RTD measurement—
all on the same module, all in a single scan. For
custom linear conversions, use the Mx+B scaling
function on any channel. You can even display a
custom 3-character engineering label like RPM or
PSI to identify your measurement units.
Versatile alarms
Alarms are available on a per-channel basis as
well. Enter a high limit, a low limit, or both. The
34970A compares each reading to its limits and
flags any out-of-range measurements. You can
assign one of four TTL alarm outputs to any input
channel to trigger external alarm lights, sirens,
or send a TTL pulse to your control system, all
without a PC connected.
Scanning made simple
The 34970A automatically builds a scan list that
includes all configured inputs (even digital inputs
from the Agilent 34907A multifunction module) in
ascending order by channel number. You can pace
scans by setting the 34970A’s internal timer for
automatic scanning at a specific interval, by manu-
ally pressing a front-panel button, or by sending a
software command or external TTL trigger pulse.
Monitor any input
A special display mode monitors a selected input
channel, continuously updating the display with
new readings—even during a scan. It’s great for
keeping an eye on a key input, or for troubleshoot-
ing your system before a test.
Nonvolatile memory adds convenience, portability
All readings are automatically time-stamped and
stored in a nonvolatile 50,000-reading memory—
enough memory to hold more than a week’s worth
of data (20 channels scanned every five minutes).
The nonvolatile memory holds your data even after
power is removed, so you can use the 34970A to
collect data at a remote location for later upload-
ing to a PC. And because the nonvolatile memory
also holds your system configuration, if you lose
power in the middle of a test, the 34970A resumes
scanning when power is returned.
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Data Logging Feature Checklist
• From 1 to 120 channels of analog input
• Measurements include dc volts, ac volts,
thermocouple, thermistor and RTD
temperature measurements, 2- and 4-wire
Ohms, dc current, ac current, frequency,
and period
•6
1/2digits (22 bits) of resolution with
0.004% basic 1-year dcV accuracy
• 50k reading nonvolatile memory
including timestamp
• Scaling and alarms available on
each channel
• Full-featured front panel for stand-alone
configuration, troubleshooting, and
data viewing
• BenchLink Data Logger II software
for configuration and data analysis
• Nonvolatile storage for five complete
instrument states

A powerful, flexible data acquisition system
for automated test
The 34970A gives you the resolution, accuracy,
repeatability, and speed you’ve come to expect
from an Agilent data acquisition system. It provides
the measurement muscle you need, along with
signal routing and control capability, in a flexible,
modular format that can grow and change to
match your varied applications.
Powerful measurements
The internal 61
/2-digit DMM brings the power and
performance of a world-class stand-alone DMM to
the 34970A, but at a fraction of the cost and in
a fraction of the space. It’s as accurate as the best
bench DMM available: 0.004% basic 1-year dcV
accuracy, 0.06% basic 1-year acV accuracy, and 0.01%
basic 1-year resistance accuracy. Our patented
Multi-slope III A-D technology offers incredible
linearity (2 ppm of reading +1 ppm of range) along
with 22 bits of real resolution. And since it is an
integrating A/D, it provides excellent noise rejec-
tion as well—a nice change from noisy PC plug-ins
and sampling A/Ds. No more averaging lots of sam-
ples just to see the real data you wanted. And if
you need high scan rates, the 34970A is capable of
delivering fully converted measurements at speeds
up to 250 ch/s.
The input section of the DMM is optically isolated
and shielded from the 34970A’s earth-referenced
circuitry and computer interface, offering up
to 300 V of input isolation. This is important for
reducing ground loop and common mode voltage
errors associated with long wiring runs and float-
ing measurement sources.
Flexible functionality
The DMM is installed inside the chassis rather
than in one of the slots, leaving all three main-
frame slots free for switch and control modules.
You can choose from eight different modules
(see page 11) to get the precise functionality you
need now—while giving you flexibility for future
expansion.
The internal DMM gives you the flexibility to meas-
ure 11 types of inputs easily and inexpensively.
The built-in signal conditioning and conversion
routines turn raw inputs directly into real informa-
tion. Each measurement channel is independently
configurable, so you can set different measurement
functions, scale factors and alarm limits, even
on adjacent channels. Advanced measurement fea-
tures such as offset compensation, variable inte-
gration time, and delay are also selectable on a
per-channel basis.
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Get better measurements with built-in
signal conditioning
The Agilent 34970A architecture offers
advantages over other data acquisition solu-
tions which rely on external or plug-in
signal conditioning modules for handling
functions other than dcV:
• Minimizes external wiring and the
resultant potential for noise and errors
to enter your system
• Reduces hidden costs and overall system
cost by avoiding unnecessary cables,
breakout boxes and signal conditioning
elements
• Simplifies your configuration—for faster,
easier setup—with fewer connections
and components
• Takes the guesswork out of error analysis.
Measurement accuracies are specified to
include all system-related errors
• Improves reliability, with fewer intercon-
nects and fewer parts that can fail

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Software drivers
Your months of test system software development
time need not go to waste. Software drivers that
support Agilent VEE and National Instruments
LabView® are available for the 34970A to make
integration into your test system easy. Standard
RS-232 and GPIB interfaces and SCPI program-
ming language make integration even easier.
Compact 60-channel data acquisition system
ATE Feature Checklist
• 3-slot cardcage with 61/2digit (22 bit)
internal DMM
• 0.004% basic 1-year dcV accuracy; 0.06%
acV accuracy
• Up to 120 single-ended measurements
or 96 matrix crosspoints in a 31/2" high,
half-rack instrument
• Eight switch and control modules include
low-frequency and RF multiplexers, matrix
and actuation switches, digital input and
output, analog output, and event recording
• Scan rates up to 250 ch/s
• GPIB and 115 kbaud RS-232 interfaces
standard
• Software drivers available to support
Agilent VEE and National Instruments
LabView
• Relay maintenance feature for system
maintenance

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Low-cost, high-quality switching for
automated test
If you don’t need the built-in measurement
capability of the 34970A, save money by ordering
it without the DMM. What you end up with is the
lowest-cost switch unit on the market. It’s an ideal
solution for routing test signals to and from your
DUT and assorted instruments, including external
DMMs, scopes, counters, and power supplies. Plus,
you can add the DMM later if your needs change.
The functionality you need
We put a lot of thought into defining and designing
the modules for the 34970A in order to cover
a broad spectrum of switching and signal routing
requirements with fewer modules. The result?
Simplified ordering and easier configuration.
And while we were at it, we improved performance
and density. The 34970A modules can switch from
microvolts to 300 volts, dc to 2 GHz, and with den-
sities as high as 120 single-ended channels or 96
matrix crosspoints per frame. Plus, simple control
capabilities like analog outputs, open collector digi-
tal outputs, and isolated Form-C relays for control-
ling higher-powered devices are available.
Easy scanning
The 34970A can easily scan with external instru-
ments. It builds a scan list that includes all enabled
low-frequency multiplexer inputs. Scans are con-
trolled with the external “channel advance” input,
or with the front panel “Step” key.
Low-cost switching system for automated testing

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Customize your Agilent 34970A with plug-in
modules
A complete selection of plug-in modules gives you
high-quality measurement, switching, and control
capabilities to choose from. Modules include both
low-frequency and RF multiplexers, a matrix switch,
a general-purpose switch, and a multifunction
module that includes digital input/output, analog
output, and totalizer capabilities. You can mix and
match modules to get just the functionality you
need right now—then change or add more channels
later as your application grows.
Modules for the 34970A are designed to make your
testing easier, faster, and more reliable. Here’s how:
Higher throughput
Our unique architecture incorporates a high-
performance microprocessor on each module, off-
loading the mainframe processor and minimizing
backplane communications for faster throughput.
More channels in less space
Surface mount construction and a highly inte-
grated design minimize the space required for
relay drive and interface circuitry. High density
on-module connectors save both board and con-
nector space normally required by a terminal
block. We use the latest technology to squeeze
the most out of the remaining board space,
giving you up to 40 single-ended channels in
roughly the same space used by many data
acquisition system terminal blocks.
Convenient connections
On-module screw-terminal connectors make
wiring more convenient. Built-in strain-relief cable
routing and cable tie points keep your wiring
secure and safe from accidental tugs and pulls.
An internal analog bus routes signals from any
of the low-frequency multiplexers directly to
the internal DMM, without the need for external
connections.
Use the chart below to help you pinpoint the
modules that meet your needs.
Agilent Modules-at-a-Glance Selection Guide
Model Type Speed Max Max Bandwidth Thermal Comments
Description (ch/sec) Volts Amps Offset Page
34901A 2-wire armature 60 300 V 1A 10 MHz < 3 µV Built-in cold junction reference
20 ch Multiplexer (4-wire selectable) 2 additional current channels (22 total) 18
34902A 2-wire reed 250 300 V 50 mA 10 MHz < 6 µV Built-in cold junction reference
16 ch Multiplexer (4-wire selectable) 19
34903A SPDT/form C 120 300 V 1A 10 MHz < 3 µV
20 ch Actuator/GP Switch 20
34904A 2-wire armature 120 300 V 1A 10 MHz < 3 µV
4 x 8 Matrix 20
34905A Common Low 60 42 V 0.7 A 2 GHz < 6 µV 1 GHz bandwidth through
Dual 4 ch RF Mux 50Ω(unterminated) BNC-to-SMB adapter cable 21
34906A Common Low 60 42 V 0.7 A 2 GHz < 6 µV 1 GHz bandwidth through
Dual 4 ch RF Mux 75Ω(unterminated) BNC-to-SMB adapter cable 21
34907A Two 8-bit digital I/O ports 42 V 400 mA Open drain
Multifunction Module 26-bit Event Counter 42 V 100 KHz Selectable input threshold
Two 16-bit Analog outputs ±12 V 10 mA dc Max 40 mA total output per frame 22
34908A 1-wire armature 60 300 V 1A 10 MHz < 3 µV Built-in cold junction reference
40 ch Single-Ended Mux (common low) No four-wire measurements 19

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Agilent Quality
We know you can’t afford instrument downtime
due to hardware failures and unscheduled mainte-
nance. That’s why our engineers designed reliability
into the 34970A: A rugged enclosure, state-of-the-
art surface mount construction throughout, reduced
parts counts, and rigorous and thorough testing on
all aspects of the product.
Take the guesswork out of relay maintenance
The 34970A uses our proprietary relay mainte-
nance system to help you to predict relay end-of-
life and avoid costly production-line downtime.
It automatically counts every individual switch
closure and stores it in nonvolatile memory on
each module. You can query the total number
of cycles on any individual channel so you can
schedule maintenance and avoid erratic end-of-
life failures.

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Spec Interpretation Guide
The following pages list the technical specifications
for the Agilent 34970A Data Acquisition/Switch
Unit and its modules. The explanations and exam-
ples below are helpful in understanding how to
interpret these specifications:
• Measurement accuracy is specified as percent
of reading plus percent of range, where reading
is the actual measured value and range is the
name of the scale (1V, 10V, etc.) —not the full
scale value (1.2V, 12V, etc.).
• DMM measurement accuracies include all switch-
ing errors. Switching errors are also listed
separately in the module specifications section.
Temperature measurement accuracies include
ITS-90 conversion errors. The thermocouple
accuracies include the reference junction error
as well.
• Accuracies are listed as either 24-hour, 90-day,
or 1-year specifications. This refers to the
length of time since the instrument’s last cali-
bration. Use the specification that matches
your calibration cycle. The 24-hour specifica-
tions are useful for determining short-term
relative performance.
EXAMPLE 1: Basic dcV accuracy
Calculate the accuracy of the following
measurement:
9 V dc input
10 V dc range
1-year accuracy specifications
Normal operating temperature (18°C–28°C)
From the following page, the 1-year accuracy is:
0.0035% of reading + 0.0005% of range
Which translates into:
(0.0035/100 x 9 V)+
(0.0005/100 x 10 V) = 365µV
For a total accuracy of:
365 µV / 9 V = 0.0041%
EXAMPLE 2: Extreme operating temperature
When the 34970A is used outside of its 18°C–28°C
temperature range, there are additional tempera-
ture drift errors to consider. Assume the same
conditions in example 1, but at a 35°C operating
temperature.
The basic accuracy is again:
0.0035% of reading + 0.0005% of range=365 µV.
Now, multiply the 10 V temperature coefficient
from the following page by the number of degrees
outside of operating range for additional error:
(0.0005% reading + 0.0001% range)
/°C x (35°C - 28°C) =
(0.0005% reading + 0.0001% range)
/°C x 7°C =
0.0035% reading + 0.0007% range = 385 µV
Total error is then:
365 µV + 385 µV = 750 µV or 0.008%
EXAMPLE 3: Thermocouple measurement accuracy
Calculating the total thermocouple reading error
is easy with the 34970A—just add the listed meas-
urement accuracy to the accuracy of your trans-
ducer. Switching, conversion, and reference junc-
tion errors are already included in the measure-
ment specification.
For this example, assume a J-type thermocouple
input reading 150°C.
From the following page, total error is:
Thermocouple probe accuracy + 1.0°C
The probe vendor specifies accuracy of 1.1°C
or 0.4%, whichever is greater.
Total error is then:
1.0ºC + 1.1 ºC = 2.1ºC total, or 1.4%
EXAMPLE 4: acV Accuracy
The acV function measures the true RMS value
of the input waveform, regardless of waveshape.
Listed accuracies assume a sinewave input. To
adjust accuracies for non-sinusoids, use the listed
crest factor adder.
For this example, assume a ±1 V square wave
input with 50% duty cycle and a 1 kHz frequency.
Accuracy for 1 V, 1 kHz sinusoid is:
0.06% reading + 0.04% range
A 50% duty cycle squarewave has a crest factor of
Peak Value / RMS value = 1 V / 1 V = 1
From Crest Factor table, add:
0.05% of reading
The total accuracy is:
0.11% of reading + 0.04% of range = 1.5 mV or 0.15%

[1] Specifications are for 1 hr warm-up and 61/2digits, Slow ac filter
[2] Relative to calibration standards
[3] 20% over range on all ranges except 300 Vdc and ac ranges and 1 Adc and ac
current ranges
[4] For sinewave input > 5% of range. For inputs from 1% to 5% of range and
< 50 kHz, add 0.1% of range additional error
[5] Typically 30% of reading error at 1 MHz, limited to 1 x 108V Hz
[6] Specifications are for 4- wire ohms function or 2-wire ohms using Scaling
to remove the offset. Without scaling, add 4 Ωadditional error in 2-wire
Ohms function
[7] Input > 100 mV. For 10 mV to 100 mV inputs multiply % of reading error x 10
[8] Specified only for inputs >10 mA
[9] For total measurement accuracy, add temperature probe error
[10] Thermocouple specifications not guaranteed when 34907A module is present
Accuracy Specifications ±(% of reading + % of range)[1]
Includes measurement error, switching error, and transducer conversion error
Temperature
Range[3] Frequency, etc. 24 Hour[2] 90 Day 1 Year Coefficient
23°C±1°C 23°C±5°C 23°C±5°C 0°C–18°C, 28°C–55°C
DC Voltage
100.0000 mV 0.0030 + 0.0035 0.0040 + 0.0040 0.0050 + 0.0040 0.0005 + 0.0005
1.000000 V 0.0020 + 0.0006 0.0030 + 0.0007 0.0040 + 0.0007 0.0005 + 0.0001
10.00000 V 0.0015 + 0.0004 0.0020 + 0.0005 0.0035 + 0.0005 0.0005 + 0.0001
100.0000 V 0.0020 + 0.0006 0.0035 + 0.0006 0.0045 + 0.0006 0.0005 + 0.0001
300.000 V 0.0020 + 0.0020 0.0035 + 0.0030 0.0045 + 0.0030 0.0005 + 0.0003
True RMS AC Voltage[4]
100.0000 mV 3 Hz–5 Hz 1.00 + 0.03 1.00 + 0.04 1.00 + 0.04 0.100 + 0.004
to 100.0000V 5 Hz–10 Hz 0.35 + 0.03 0.35 + 0.04 0.35 + 0.04 0.035 + 0.004
10 Hz–20 kHz 0.04 + 0.03 0.05 + 0.04 0.06 + 0.04 0.005 + 0.004
20 kHz–50 kHz 0.10 + 0.05 0.11 + 0.05 0.12 + 0.05 0.011 + 0.005
50 kHz–100 kHz 0.55 + 0.08 0.60 + 0.08 0.60 + 0.08 0.060 + 0.008
100 kHz–300 kHz[5] 4.00 + 0.50 4.00 + 0.50 4.00 + 0.50 0.20 + 0.02
300.0000V 3 Hz–5 Hz 1.00 + 0.05 1.00 + 0.08 1.00 + 0.08 0.100 + 0.008
5 Hz–10 Hz 0.35 + 0.05 0.35 + 0.08 0.35 + 0.08 0.035 + 0.008
10 Hz–20 kHz 0.04 + 0.05 0.05 + 0.08 0.06 + 0.08 0.005 + 0.008
20 kHz–50 kHz 0.10 + 0.10 0.11 + 0.12 0.12 + 0.12 0.011 + 0.012
50 kHz–100 kHz 0.55 + 0.20 0.60 + 0.20 0.60 + 0.20 0.060 + 0.020
100 kHz–300 kHz[5] 4.00 + 1.25 4.00 + 1.25 4.00 + 1.25 0.20 + 0.05
Resistance[6]
100.0000Ω1 mA current source 0.0030 + 0.0035 0.008 + 0.004 0.010 + 0.004 0.0006 + 0.0005
1.000000 kΩ1 mA 0.0020 + 0.0006 0.008 + 0.001 0.010 + 0.001 0.0006 + 0.0001
10.00000 kΩ100 µA 0.0020 + 0.0005 0.008 + 0.001 0.010 + 0.001 0.0006 + 0.0001
100.0000 kΩ10 µA 0.0020 + 0.0005 0.008 + 0.001 0.010 + 0.001 0.0006 + 0.0001
1.000000 MΩ5.0 µA 0.002 + 0.001 0.008 + 0.001 0.010 + 0.001 0.0010 + 0.0002
10.00000 MΩ500 nA 0.015 + 0.001 0.020 + 0.001 0.040 + 0.001 0.0030 + 0.0004
100.0000 MΩ500 nA/10 MΩ0.300 + 0.010 0.800 + 0.010 0.800 + 0.010 0.1500 + 0.0002
Frequency and Period[7]
100 mV 3 Hz–5 Hz 0.10 0.10 0.10 0.005
to 300 V 5 Hz–10 Hz 0.05 0.05 0.05 0.005
10 Hz–40 Hz 0.03 0.03 0.03 0.001
40 Hz–300 kHz 0.006 0.01 0.01 0.001
DC Current (34901A only)
10.00000 mA <0.1 V burden 0.005 + 0.010 0.030 + 0.020 0.050 + 0.020 0.002+ 0.0020
100.0000 mA <0.6 V 0.010 + 0.004 0.030 + 0.005 0.050 + 0.005 0.002 + 0.0005
1.000000 A <2 V 0.050 + 0.006 0.080 + 0.010 0.100 + 0.010 0.005 + 0.0010
True RMS AC Current (34901A only)
10.00000 mA 3 Hz–5 Hz 1.00 + 0.04 1.00 + 0.04 1.00 + 0.04 0.100 + 0.006
and[4] 1.000000 A 5 Hz–10 Hz 0.30 + 0.04 0.30 + 0.04 0.30 + 0.04 0.035 + 0.006
10 Hz–5 kHz 0.10 + 0.04 0.10 + 0.04 0.10 + 0.04 0.015 + 0.006
100.0000 mA[8] 3 Hz–5 Hz 1.00 + 0.5 1.00 + 0.5 1.00 + 0.5 0.100 + 0.06
5 Hz–10 Hz 0.30 + 0.5 0.30 + 0.5 0.30 + 0.5 0.035 + 0.06
10 Hz–5 kHz 0.10 + 0.5 0.10 + 0.5 0.10 + 0.5 0.015 + 0.06
Temperature Type 1-Year Accuracy[9] Extended Range 1-Year Accuracy[9]
Thermocouple[10] B 1100°C to 1820°C 1.2°C 400°C to 1100°C 1.8°C
E -150°C to 1000°C 1.0°C -200°C to -150°C 1.5°C
J -150°C to 1200°C 1.0°C -210°C to -150°C 1.2°C
K -100°C to 1200°C 1.0°C -200°C to -100°C 1.5°C 0.03 °C
N -100°C to 1300°C 1.0°C -200°C to -100°C 1.5°C
R 300°C to 1760°C 1.2°C -50°C to 300°C 1.8°C
S 400°C to 1760°C 1.2°C -50°C to 400°C 1.8°C
T -100°C to 400°C 1.0°C -200°C to -100°C 1.5°C
RTD R0from 49 Ωto 2.1 kΩ-200°C to 600°C 0.06°C 0.003 °C
Thermistor 2.2 k, 5k, 10k -80°C to 150°C 0.08°C 0.002 °C

15
Measurement Characteristics[8]
DC Voltage
Measurement Method Continuously Integrating
Multi-slope III A-D Converter
A-D Linearity 0.0002% of reading + 0.0001 % of range
Input Resistance
100 mV, 1 V, 10 V ranges Selectable 10 MΩor > 10,000 MΩ
100 V, 300 V ranges 10 MΩ±1%
Input Bias Current < 30 pA at 25°C
Input Protection 300 V all ranges
True RMS AC Voltage
Measurement Method AC coupled True RMS — measures the
AC component of the input with up to
300 Vdc of bias on any range
Crest Factor Maximum of 5:1 at Full Scale
Additional Crest Factor
Errors (non-sinewave) Crest Factor 1-2 0.05 % of reading
Crest Factor 2-3 0.15 % of reading
Crest Factor 3-4 0.30 % of reading
Crest Factor 4-5 0.40 % of reading
Input Impedance 1 MΩ± 2% in parallel with 150 pF
Input Protection 300 Vrms all ranges
Resistance
Measurement Method Selectable 4-wire or 2-wire Ohms
Current source referenced to LO input
Offset Compensation Selectable on 100Ω, 1kΩ, 10kΩranges
Maximum Lead Resistance 10% of range per lead for 100 Ωand
1 kΩranges. 1 kΩon all other ranges
Input Protection 300 V on all ranges
Frequency and Period
Measurement Method Reciprocal counting technique
Voltage Ranges Same as AC Voltage function
Gate Time 1s, 100 ms, or 10 ms
Measurement Timeout Selectable 3 Hz, 20 Hz, 200 Hz LF limit
DC Current
Shunt Resistance 5 Ωfor 10 mA, 100 mA; 0.1 Ωfor 1 A
Input Protection 1A 250 V fuse on 34901A module
True RMS AC Current
Measurement Method Direct coupled to the fuse and shunt.
AC coupled True RMS measurement
(measures the ac component only)
Shunt Resistance 5 Ωfor 10 mA; 0.1 Ωfor 100 mA, 1 A
Input Protection 1A 250 V fuse on 34901A module
Thermocouple
Conversion ITS-90 software compensation
Reference Junction Type Internal, Fixed, or External
Open thermocouple Check Selectable per channel. Open >5kΩ
Thermistor 44004, 44007, 44006 series
RTD = 0.00385 (DIN) and = 0.00391
Measurement Noise Rejection 60 (50) Hz[1]
dc CMRR 140 dB
ac CMRR 70 dB
Integration Time Normal Mode Rejection[2]
200 plc/3.33s (4s) 110 dB[3]
100 plc/1.67s (2s) 105 dB[3]
20 plc/333 ms (400 ms) 100 dB [3]
10 plc/167 ms (200 ms) 95 dB [3]
2 plc/33.3 ms (40 ms) 90 dB
1 plc/16.7 ms (20 ms) 60 dB
< 1 plc 0 dB
Operating Characteristics[4]
Single Channel Measurement Rates [5]
Function Resolution [9] reading/s
dcV, 2-wire Resistance 61 /2digits (10 plc) 6 (5)
51 /2digits (1 plc) 57 (47)
41 /2digits (0.02 plc) 490
Thermocouple 0.1°C (1 plc) 49 (47)
(0.02 plc) 280
RTD, Thermistor 0.01°C (10 plc) 6 (5)
0.1°C (1 plc) 47 (47)
1°C (0.02 plc) 280
acV 61 /2Slow (3 Hz) 0.14
61 /2Med (20 Hz) 1
61 /2Fast (200 Hz) 8
61 /2[6] 100
Frequency, Period 61 /2digits (1s gate) 1
51 /2digits (100 ms) 9
41 /2digits (10 ms) 70
System Speeds [7]
INTO Memory ch/s
single channel dcV 490
34902A scanning dcV 250
34907A scanning digital in 250
34902A scanning dcV with scaling & 1 alarm fail 220
34907A scanning totalize 170
34902A scanning temperature 160
34902A scanning acV[6] 100
34902A scanning dcV/Ohms on alternate channels 90
34901A/34908A scanning dcV 60
INTO and OUT of memory to GPIB or RS-232 (init, fetch)
34902A scanning dcV 180
34902A scanning dcV with timestamp 150
OUT of memory to GPIB[10]
Readings 800
Readings with timestamp 450
Readings with all format options ON 310
OUT of memory to RS-232
Readings 600
Readings with timestamp 320
Readings with all format options ON 230
DIRECT to GPIB or RS-232
single channel dcV 440
34902A scanning dcV 200
single channel MEAS DCV 10 / MEAS DCV 1 25
single channel MEAS DCV/ MEAS OHMS 12
[1] For 1 KΩunbalance in LO lead
[2] For power line frequency ±0.1%
[3] For power line frequency ±1% use 80 dB or ±3% use 60 dB
[4] Reading speeds for 60 Hz and (50 Hz) operation
[5] For fixed function and range, readings to memory, scaling and alarms off,
AZERO OFF
[6] Maximum limit with default settling delays defeated
[7] Speeds are for 41/2digits, delay Ø, display off, autozero off.
Using 115 kbaud RS-232 setting
[8] Isolation voltage (ch - ch, ch - earth) 300 Vdc, ac rms
[9] 6 1/2digits = 22 bits, 51/2digits = 18 bits, 41/2digits = 15 bits
[10] Assumes relative time format (time since start of scan)

16
System Specifications
Scanning Inputs
Analog 34901A, 34902A, and 34908A
multiplexer channels
Digital 34907A digital in and totalize
Scan list Scans channels in ascending order
Scan Triggering
Source Interval, external, button press, software,
or on monitor channel alarm
Scan count 1 to 50,000 or continuous
Scan interval 0 to 99 hours; 1ms step size
Channel delay 0 to 60 seconds per channel; 1 ms step size
External trig delay <300 µs. With monitor on <200 ms
External trig jitter <2 ms
Alarms
Analog inputs Hi, Lo, or Hi + Lo evaluated each scan
Digital inputs 34907A digital in maskable pattern match
or state change
34907A totalize: Hi limit only
Monitor channel Alarm evaluated each reading
Alarm Outputs 4 TTL compatible
Selectable TTL logic Hi or Lo on fail
Latency 5 ms (typical)
Memory
Battery backed, 4 year typical life[1]
Readings 50,000 with timestamp
Readable during scan
States 5 instrument states with user label
Alarm Queue Up to 20 events with channel number,
reading, and timestamp
System Features
Per-channel Math Individual Mx + B scaling and
Min/Max/Average calculated real time
Power Fail Recovery Resumes scanning automatically
Relay maintenance Counts each relay closure and stores
on module User resettable
Real-time clock Battery-backed, 4-year typical life[1]
General Specifications
Power Supply 100V/120V/220V/240V ±10%
Power Line Frequency 45 Hz to 66 Hz automatically sensed
Power Consumption 12 W (25 VA peak)
Operating Environment Full accuracy for 0°C to 55°C
Full accuracy to 80% R.H. at 40°C
Storage Environment -40°C to 70°C[1]
Weight Net: 3.6 kg (8.0 lbs)
Safety Conforms to CSA, UL-1244, IEC 1010 Cat I
RFI and ESD CISPR 11, IEC 801/2/3/4
Software
Agilent BenchLink Data Logger II
(not included with Option 001)
System Requirements[2]
Operating System Windows 98SE, NT® 4.0 SP6a, 2000 SP4, XP
Adobe®Acrobat®Reader V5.0 or higher
(to view documentation)
Microsoft®Internet Explorer V5.0 or higher
(required when using Windows NT)
Controller Recommend Pentium®4, 800 MHz or
greater, Min: Pentium III, 500 MHz
RAM Recommend 256MB or greater, Min 128MB
Disk Space Recommend 200MB, Min 70MB
Display 800x600 resolution, 256 colors
Computer Interfaces[3]
GPIB Agilent and National Instruments PCI-GPIB
LAN-to-GPIB E5810A
USB-to-GPIB 82357A
RS-232 (Serial Port) PC COM 1-4
Agilent BenchLink Features
Configuration Spreadsheet-like setup page
Upload and Download instrument setups
Computed channels using + - */, dB, dBm,
dBV, x2, √— x and full, 1 /2, or 1/4bridge strain
Graphical Displays Real-time and historical data displays
Add, delete, size, and configure real time
Strip chart with markers and alarm indication,
bar and scatter charts, Histogram with
statistics, Bar meter, Digital meter, and
Data table
Graphical Controls Sliders, switches, buttons, and LED lights
Alarm / Limit testing Start/Stop scanning on alarm condition
Control 34903A relay state or 34907A
digital output on alarm
Data Real time streamed (saved) to disk
Copy data or graphics to windows clipboard
Export user-selected data to .CVS, .XML,
or .TXT formats
Event logging Automatic entry of alarms and errors
Enter user notes real time
Printing Setup spreadsheet, all graphics, and
event log entries
Instrument Driver Support for Programming Languages
Universal Compatible with Windows 95 and NT
Instrument Driver[5] Agilent VEE 3.2 or greater
Visual Basic 4.0,
LabWindows CVI 4.0,
LabVIEW 4.0
Labview Driver (VI) LabVIEW 4.0
[1] Storage at temperatures above 40°C will decrease battery life
[2] Software provided on CD-ROM and includes utility to create floppy disks for
installation
[3] Interface and driver must be purchased and installed separately
[4] 90 MHz Pentium, 20 MB RAM
[5] Requires VISA command library for IEEE-488
Microsoft, Windows, and Windows NT are U.S. registered trademarks of
Microsoft Corporation.
Adobe and Acrobat are trademarks of Adobe Systems Incorporated.
Pentium is a U.S. registered trademark of Intel Corporation.

17
Modules Specifications
The Agilent 34970A accuracy specifications already
include the switching offset and reference junction
errors shown below. These errors are listed sepa-
rately for determining system error with external
measurement devices.
Up to three modules, in any combination, can be
inserted into a single mainframe. The 34970A’s
internal DMM connections are accessible only
through the 34901A, 34902A, and 34908A low-
frequency multiplexers.
On-module screw terminals accept wire sizes from
16 gage to 22 gage. Twenty-gage wire is recom-
mended for high channel count applications. The
34905A and 34906A RF Multiplexers use SMB
connectors. A standard set of (10) BNC-to-SMB
adapter cables is provided with each RF module
for convenient BNC connections.
Multiplexer Actuator Matrix RF Multiplexer Multifunction
34901A 34902A[1] 34908A 34903A 34904A 34905A 34906A 34907A
General
Number of Channels 20 + 2 16 40 20 4 x 8 Dual 1 x 4 See page 22
2/4 wire 2/4 wire 1 wire SPDT 2 wire 50 Ω75 Ωfor module
Connects to Internal DMM • • • specifications
Scanning Speed 60 ch/s 250 ch/s 60 ch/s
Open/Close Speed 120/s 120/s 70/s 120/s 120/s 60/s
Input
Voltage (dc , ac rms)[2] 300 V 300 V 300 V 300 V 300 V 42 V
Current (dc , ac rms) 1A 50mA 1A 1A 1A 0.7A
Power (W , VA) 50 W 2 W 50 W 50 W 50 W 20 W
DC Characteristics
Offset Voltage [3] < 3uV < 6uV < 3uV < 3uV < 3uV < 6uV
Initial Closed Channel R [3] < 1 Ω< 1 Ω< 1 Ω< 0.2 Ω< 1 Ω< 0.5 Ω
Isolation ch-ch, ch-earth > 10 G Ω> 10 G Ω> 10 G Ω> 10 G Ω> 10 G Ω> 1 G Ω
AC Characteristics
Bandwidth[4] 10 MHz 10 MHz 10 MHz 10 MHz 10 MHz 2 GHz [5] 2 GHz [5]
Insertion Loss (dB) 10 MHz —————-0.1 -0.1
100 MHz —————-0.4 -0.4
500 MHz —————-0.6 -0.5
1GHz—————-1 -1
1.5 GHz —————-1.2 -1.5
2GHz—————-3 -2
SWR 10MHz—————1.02 1.02
100 MHz —————1.05 1.05
500 MHz —————1.20 1.25
1GHz—————1.20 1.40
1.5 GHz —————1.30 1.40
2GHz—————1.40 2.00
ch-ch Cross Talk (dB)[4] 10 MHz -45 -45 -18[6] -45 -33 -100 -85
100 MHz —————-85-75
500 MHz —————-65-65
1GHz—————-55-50
1.5 GHz —————-45-40
2GHz—————-35-35
Risetime < 300 ps
Signal Delay < 3 ns
Capacitance HI - LO < 50 pF < 50 pF < 50 pF < 10 pF < 50 pF < 20 pF
LO - Earth < 80 pF < 80 pF < 80 pF < 80 pF < 80 pF —
Volt-Hertz limit 1081081081081081010
Other
T/C Cold Junction Accuracy[3]
(typical) 0.8°C 0.8°C 0.8°C
[8]
Switch Life No Load (typical) 100M 100M 100M 100M 100M 5M 5M
Rated Load (typical)[7] 100k 100k 100k 100k 100k 100k 100k
Temperature Operating all cards — 0°C to 55°C
Storage all cards — -20°C to 70°C
Humidity (non-condensing) all cards — 40°C/80% RH
[1] Not recommended for connection to ac line without external transient suppression
[2] Channel-to-channel or channel-to-earth
[3] Errors included in DMM measurement accuracy specifications
[4] 50Ωsource, 50Ωload
[5] Bandwidth direct to card SMB connectors
[6] Isolation within channel 1 to 20 or 21 to 40 banks is -40 dB
[7] Applies to resistive loads only
[8] Thermocouple measurements not recommended with 34908A
module due to common lo configuration

18
Multiplexer Selection Guide
Choose between the broad functionality of the
34901A, the high speed scanning of the 34902A,
or the single-ended density of the 34908A. These
three modules are the only way to connect to the
34970A internal DMM. They can be used to scan
with external instruments as well.
All multiplexer modules employ break-before-
make scanning, ensuring only one closed channel
(or channel pair) at a time. Multiple channel
closures are allowed on the 34901A and 34902A
modules when not configured for scanning.
The 34908A does not allow multiple channel clo-
sures at any time.
34901A
20-Channel General-Purpose Multiplexer
• 60 ch/s scanning
• Two- and four-wire scanning
• Built-in thermocouple reference junction
• 300 V switching
The Agilent 34901A is the most versatile multi-
plexer for general purpose scanning. It combines
dense, multifunction switching with 60 channel/
second scan rates to address a broad spectrum
of data acquisition applications.
Two- and four-wire channels can be mixed on
the same module. Two additional fused inputs
(22 channels total) route up to 1A of current to
the internal DMM, allowing ac and dc current
measurements without the need for external
shunt resistors.
34901A 34902A 34908A
Number of Channels 20 + 2 16 40
Max scan speed 60 ch/s 250 ch/s 60 ch/s
Number of contacts 2 or 4 2 or 4 1
Temperature
Thermocouple •••
2-wire RTD •••
4-wire RTD ••
Thermistor •••
dc Volts •••
ac Volts •••
2-wire Ohms •••
4-wire Ohms ••
Frequency •••
Period •••
dc current •
ac current •
Backplane Switches
Internal
DMM Input
01
10
Com
H
L
H
L
H
L
H
L
H
L
H
L
I
L
I
L
I
L
I
L
H
L
H
L
T
Com
(4W Sense)
11
20
21
Current
Channels
22
Com
(Current)
Fuse
Fuse
Internal
DMM Input
(4W Sense)
Internal
DMM Input
(Current)
Reference
Junction
Sensor
Channel Switches
Bank Switch
Shunt Switches

19
34902A
16-Channel High-Speed Multiplexer
• 250 ch/s scanning
• Two- and four-wire scanning
• Built-in thermocouple reference junction
The Agilent 34902A employs reed relays to achieve
scan rates up to 250 channels per second. Use this
module for high-throughput automated test appli-
cations as well as high-speed data logging and
monitoring tasks.
Sixteen two-wire inputs switch up to 300 V.
Two- and four-wire channels may be mixed on
the same module. User provided shunt resistors
are required for current measurements.
34908A
40-Channel Single-Ended Multiplexer
• 60 ch/s scanning
• Single-wire switching for common-low
applications
• Built-in thermocouple reference junction
Use the Agilent 34908A for the greatest density
in common-low applications, such as battery test,
component characterization, and benchtop testing.
Each module switches 40 one-wire inputs. All
two-wire internal measurements except current
are supported. The module low connection is
isolated from earth and can float up to 300 V.
Backplane Switches
Internal
DMM Input
01
08
Com
H
L
H
L
H
L
H
L
H
L
H
L
H
L
H
L
T
Com
(4W Sense)
09
16
Internal
DMM Input
(4W Sense)
Reference
Junction
Sensor
Channel Switches
Bank Switch
01
20
21
40
Com
Com
H
H
L
H
H
H
L
H
Channel Switches
Backplane
Switch
Bank Switch
Internal
DMM Input
Reference
Junction
Sensor
T
Note: Thermocouples must be electri-
cally isolated from each other to avoid
current loops and subsequent meas-
urement errors.
Note: Not recommended for connec-
tion to ac line without external tran-
sient suppression.

20
34903A
20-Channel Actuator/General Purpose Switch
• SPDT (Form C) latching relays
• 300 V, 1A actuation and control
This general-purpose switch module has 20 inde-
pendent single-pole, double-throw (SPDT) relays.
Use it to cycle power to products under test, con-
trol indicator and status lights, and to actuate
external power relays and solenoids. Combine it
with matrix and multiplexer modules to build cus-
tom switch systems. Its 300 V, 1A contacts can
handle up to 50 W, enough for many power line
switching applications.
34904A
4x8 Two-wire Matrix Switch
• 32 two-wire crosspoints
• 300 V, 1A switching
The Agilent 34904A gives you the most flexible
connection path between your device under test
and your test equipment, allowing different instru-
ments to be connected to multiple points on your
DUT at the same time.
Rows or columns may be connected between multi-
ple modules to build 8x8, 4x16 or larger matrices,
with up to 96 crosspoints in a single frame.
01
20
NC
COM
NO
NC
COM
NO
Row 1
Row 2
Row 3
Row 4
Channel 31
(Row 3, Column 1)
Col 1
H L
Col 2
H L
Col 8
H L
H
L
H
L
H
L
H
L
H
H
L
L