Specifications

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
applications 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 mea-
surement errors.
Note: Not recommended for con-
nection to ac-line without external
transient suppression.