User`s guide

Easier signal routing with four
2-wire internal analog buses. You can route
your measurements directly to the inter-
nal DMM, or you can connect to external
instruments through the analog bus con-
nector on the rear of the mainframe. And
since you have four 2-wire buses, you can
dedicate one bus for use with the internal
DMM and use the other three buses for
module extensions or additional signal rout-
ing between modules, reducing your wiring
needs.
You can define up to 500 switch sequences
to control complex signal routing and
the order of switch closures. Assign a
sequence, give it a name and then execute
it with the name you created.
Switch sequences are downloaded and
stored in the instrument for ease of pro-
gramming and increased throughput.
External trigger capabilities make it easy for
you to time and synchronize measurements
and other events. This can help you deter-
mine when to begin or end an acquisition.
Measurements you can trust
Get proven performance from Agilent
instruments, with the resolution, repeat-
ability, speed, and accuracy you’ve come
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The 34980A offers built-in signal condition-
ing and modular flexibility. When you use it
with the internal DMM, you can configure
each channel independently for the mea-
surements you choose. It includes a variety
of features that give you confidence in your
measurements:
• 6½digitsofresolutionwith.004%
of accuracy with DC voltage
measurements
• Alarmsperchannel—highlimit,
low limit, or both
• Mathfunctions—useMx+Bfor
custom linear conversions and
converting raw inputs
• Built-inthermocouplereference
for temperature measurements (34921T)
• Time-stampedreadings
• AddmoreformulaswithBenchLinkData
LoggerSoftware
The integrated DMM is mounted inside
the mainframe and does not consume
any of the eight user-available slots. You
can access the DMM through any switch
module that connects to the analog bus,
or directly from the analog bus connector
on the rear of the mainframe. The internal
DMM gives you the flexibility to measure
11 types of inputs:
• Temperaturewiththermocouples,RTDs,
or thermistors (with 34921A)
• DCandACvoltage
• 2-and4-wireresistance
• Frequencyandperiod
• DCandACcurrent
You can control the DMM directly, or
configure it to work in conjunction with
the switches. Each switch channel can be
configured independently for measurement
functions, scale factors and alarm limits.
Advanced measurement features such as
offset compensation, variable integration
time, and delay are also selectable on a
per-channel basis.
The DMM inputs are shielded and opti-
cally isolated from the 34980A’s earth-
referenced circuitry and computer interface,
and as a result, you get up to 300 V of input
isolation. This is important for reducing
ground-loops and common-mode voltage
errors associated with long wiring runs and
floating sources.
Simple DMM calibration is
accomplished with just the analog bus con-
nection on the rear panel of the mainframe.
You don’t need to remove the mainframe
from the rack or dedicate a channel for
calibration.
Modules provide flexible system
stimulus and control
System control—with analog outputs,
open-collector digital outputs, clock genera-
tion, and isolated Form-C relays for control-
ling external devices. Additionally, with the
microwave switch/attenuator driver, high-
frequency switches and attenuators can be
efficiently controlled external to the 34980A
mainframe.
Analog sources—output either voltage or
current. You can configure the 4-channel
isolated D/A converter as a point-to-point
arbitrary waveform generator that lets you
define up to 500,000 points per waveform.
Digital patterns—send or receive digital
data from your device under test. With on-
board memory you can output communica-
tion protocols and bit streams or monitor
digital input patterns and interrupt when a
user-defined pattern is detected.
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