The IN74ACT138 is identical in pinout to the LS/ALS138, HC/HCT138. The IN74ACT138 may be used as a level converter for interfacing TTL or NMOS outputs to High Speed CMOS inputs. The IN74ACT138 decodes a three-bit Address to one-of-eight active-lot outputs. This device features three Chip Select inputs, two active-low and one active-high to facilitate the demultiplexing, cascading, and chip-selecting 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. TTL/NMOS Compatible Input Levels Outputs Directly Interface to CMOS, NMOS, and TTL Operating Voltage Range: 4.5 to 5.5 V