One-Wire (Single-Ended) Multiplexers
On the HP 34908A multiplexer, all of the 40 channels switch the HI
input only, with a common LO for the module. The module also provides
a thermocouple reference junction for making thermocouple measurements
(for more information on the purpose of an isothermal block, see page 350).
Two-Wire Multiplexers
The HP 34901A and HP 34902A multiplexers switch both HI and LO
inputs, thus providing fully isolated inputs to the internal DMM or an
external instrument. These modules also provide a thermocouple
reference junction for making thermocouple measurements (for more
information on the purpose of an isothermal block, see page 350).
Channel 1
Channel 2
Channel 3
Channel 4
To DMM
Note: Only one channel can be closed at a time; closing one channel will open the
previously closed channel.
Channel 1
Channel 2
Channel 3
Channel 4
To DMM
Note: If any channels are configured to be part of the scan list, you cannot close
multiple channels; closing one channel will open the previously closed channel.
Module Reference
8
Chapter 8 Tutorial
Low-Level Signal Multiplexing and Switching
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