34922A 70-Channel Armature Multiplexer - Agilent Technologies 34921A User Manual

34922A 70-Channel Armature Multiplexer

The high- density 34922A 70- Channel Armature Multiplexer (70- Ch Arm
MUX) is divided into two banks with 35 latching armature switches
(channels 1- 35 and 36- 70) in each. This module also contains eight
armature Analog Bus relays (channels 911- 914 and 921- 924), four on each
bank that can connect the bank relays to the system Analog Buses.
Through ABus1 and ABus2 you can connect any of the channels to the
internal DMM for voltage or resistance measurements. Refer to the
simplified schematic on
Using program commands or the mainframe front panel, you can control
each of the channel switches individually, and thus configure the 34922A
in these modes:
• two independent 35- channel 2- wire MUXes. This configuration requires
• one 35- channel 4- wire MUX. This configuration requires neither using
• one 70- channel 2- wire MUX. You must use external wiring or connect
This module has capability to scan as many as 100 channels/second using
the internal DMM. With the automatic "break- before- make" connection
operation, you are assured that no two signals are connected to each other
during a scan. When using the module in a non- scanning mode, you can
close as many channels as you wish.
This module is interlock protected, which means whenever the D- sub
connector end of the modules is exposed, the Analog Bus relays
automatically open and disconnect from the Analog Bus. For more
information, see
Connectors"
When the power is off, all channel relays maintain state, and the Analog
Bus relays open.
Agilent 34921A-34925A Low Frequency Multiplexer Modules User's Guide
neither using external wiring nor connecting through the internal
Analog Buses.
external wiring nor connecting through the internal Analog Buses.
For 4- wire resistance measurements, the instrument automatically pairs
channel n on Bank 1 (source) with channel n+35 on Bank 2 (sense) to
provide these connections. Four- wire controls occur only when doing
4- wire measurement operations through the internal DMM, such as
MEASure:FRESistance? or scanning a channel previously configured
as 4- wire.
through the internal Analog Bus relays for this configuration.
For example, closing Analog Bus channels 913 and 923 connects
Bank 1 and Bank 2 through ABus3. Or, externally you can connect
COM1 to COM2 to create this configuration.
"Safety Interlock"
on page 15.
34922A 70-Channel Armature Multiplexer
page 14.
on page 3 and "34922A D- Sub
13