The ’HC251 and ’HCT251 are 8-channel digital multiplexers with three-state outputs, fabricated with high-speed silicongate CMOS technology. Together with the low power consumption of standard CMOS integrated circuits, they possess the ability to drive 10 LSTTL loads. The three-state feature makes them ideally suited for interfacing with bus lines in a bus-oriented system.

This multiplexer features both true (Y) and complement (Y) outputs as well as an output enable (OE) input. The OE must be at a low logic level to enable this device. When the OE input is high, both outputs are in the high-impedance state. When enabled, address information on the data select inputs determines which data input is routed to the Y and Y outputs. The ’HCT251 logic family is speed, function, and pin-compatible with the standard ’LS251.