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TECHNICAL DATA
IN74HC138A
1-of-8 Decoder/Demultiplexer
The IN74HC138A is identical in pinout to the LS/ALS138. The device inputs are compatible with standard CMOS outputs; with pullup resistors, they are compatible with LS/ALSTTL outputs. The IN74HC138A decodes a three-bit Address to one-of-eight activelow outputs. This device features three Chip Select inputs, two active-low and one active-high to facilitate the demultiplexing, cascading, and chipselecting functions. The demultiplexing function is accomplished by using the Address inputs to select the desired device output; one of the Chip Selects is used as a data input while the other Chip Selects are held in their active states. • Outputs Directly Interface to CMOS, NMOS, and TTL • Operating Voltage Range: 2.0 to 6.