The MC74VHCT157A is an advanced high speed CMOS quad 2channel multiplexer fabricated with silicon gate CMOS technology. It achieves high speed operation similar to equivalent Bipolar Schottky TTL while maintaining CMOS low power dissipation. It consists of four 2input digital multiplexers with common select (S) and enable (E) inputs. When E is held High, selection of data is inhibited and all the outputs go Low.