The M54/74HC138 is a high speed CMOS 3 TO 8 LINE DECODER fabricated in silicon gate C 2MOS technology. It has the same high speed performance of LSTTL combined with true CMOSlow power consumption. If the device is enabled, 3 binary select inputs (A, B and C) determine which one of the outputs will go low. If enable input G1 is held low or either G2A or G2B is held high, the decoding function is inhibited and all the 8 outputs go high. Three enable inputs are provided to ease cascade connection and application of address decoders for memory systems. All inputs are equipped with protection circuits against static discharge and tran- sient excess voltage.This integrated circuit has input and output characteristics that are fully compatible with 54/74 LSTTL logic families. M54/74HCT devices 2