Agilent Technologies L4400 manual Low Frequency Multiplexer Switch Instrument

4L4421A 40-Channel Armature Multiplexer

Low Frequency Multiplexer Switch Instrument

The L4421A low frequency multiplexer (MUX) switch module features two banks of channels that provide broad multiplexing and measuring capabilities. You can close more than one channel in each bank simultaneously (N:1 configuration) on the multiplexer.

N O TE	Safety Interlock The Analog Buses of the L4400 series
	instruments are capable of carrying 300V signals. The L4421A
	instrument has a hardware Safety Interlock feature that
	automatically opens the analog bus relays when the associated
	interlock pins on the D-sub connectors (faceplate) lose continuity.
	This prevents signals on the analog buses from being present on
	the D-sub connector pins. Optional terminal blocks available from
	Agilent automatically provide continuity for these interlock pins. If
	cables are used, you must provide continuity for the interlock pins in
	your DUT assembly. See the pinout information later in this chapter
	for the location of interlock pins on each module.
	The L4421A has analog bus relays on each of its two banks.
	Therefore, the interlock pins are present on both the Bank 1 and
	Bank 2 D-sub connectors on the module.
	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 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.

L4421A Measurement Functions

The L4421A supports the measurement functions shown in Table 4- 1. Measurements are made by routing the signals on the multiplexer to a separate digital multimeter (DMM) instrument using the L4421A analog bus.

100 L4400 User’s Guide