Agilent Technologies Switch/Measure manual Low Frequency Multiplexer Switch Modules

4Low Frequency Multiplexer Switch Modules

Low Frequency Multiplexer Switch Modules

All low frequency multiplexer (MUX) switch modules feature two banks of channels that provide broad multiplexing and measuring capabilities. You can connect a MUX to an external instrument, and/or switch multiple analog signals to the internal DMM. With the 34921A, 34922A, 34923A, and the 34924A modules, you can close more than one channel in each bank simultaneously (N:1 configuration). As the 34925A module is protected with overvoltage circuitry, you can close only one channel in each bank at one time (1:N configuration).

And, you can connect multiple MUXes to the built- in Analog Buses, which allow you to scan as many as 560 2- wire (differential) channels or 640 1- wire (single- ended) channels in one 34980A mainframe.

N O TE	Safety Interlock Analog Buses of the 34980A can carry 300 V
	signals. MUX and matrix modules with Analog Bus relays have a
	hardware Safety Interlock feature that forces Analog Bus relays
	open when their associated D-sub connector (faceplate) interlock
	pins lose continuity. This prevents signals from the Analog Buses
	from being present on D-sub connector pins. Optional Agilent
	terminal blocks automatically provide continuity for the interlock
	pins. When the terminal blocks are not used, you must provide
	continuity for the interlock pins in the DUT assembly. See pinout
	drawings and tables in this chapter for the location of interlock pins
	on the module of interest.
	MUX modules with Analog Bus connections have Analog Bus
	relays on each of their two banks. Therefore, the interlock pins are
	found on both Bank 1 and Bank 2 D-sub connectors of the MUX
	modules.
	Normally, if you attempt to connect to the Analog Buses without a
	terminal block or cable connected, an error is generated. The
	SYSTem:ABUS:INTerlock:SIMulate command allows
	you to temporarily disable errors generated by the Safety Interlock
	feature and enables the Safety Interlock simulation mode. Although
	Safety Interlock errors are suppressed in this mode, the actual
	Analog Bus relays affected by the Safety Interlock are disabled as
	long as no terminal block or cable is connected to the module.

96 34980A User’s Guide