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TECHNICAL DATA
IN74AC138
1-of-8 Decoder/Demultiplexer
High-Speed Silicon-Gate CMOS
The IN74AC138 is identical in pinout to the LS/ALS138, HC/HCT138. The device inputs are compatible with standard CMOS outputs; with pullup resistors, they are compatible with LS/ALS outputs. The IN74AC138 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.