Logic device/transceiver/encoder

The MM74HC138 decoder is fabricated on an advanced silicon-gate CMOS process and is ideal for memory address decoding or data routing applications. The circuits feature high noise immunity and low power consumption typically associated with CMOS circuits but are comparable in speed to low power Schottky TTL logic. The MM74HC138 has 3 binary select inputs (A, B, and C). These inputs determine which of the eight normally high outputs will go low if the device is enabled. Two active-low enables and one active-high enable (G1, G2A#, and G2B#) are provided to simplify cascading of decoders. The output of the decoder can drive 10 low power Schottky TTL equivalent loads and is functionally and pin equivalent to the 74LS138. All inputs are protected from electrostatic discharge damage by diode clamping to VCC and ground.