DESCRIPTION
These devices consist of four 2-input digital multiplexers with common select and strobe inputs. The HCT158 is an inverting multiplexer while the HCT157 is a non-inverting multiplexer. When the STROBE input is held High, selection of data is inhibited and all the outputs become Low in the M74HCT157 and High in the M74HCT158. The SELECT decoding determines whether the A or B inputs get routed to their corresponding Y outputs. All inputs are equipped with protection circuits against static discharge and transient excess voltage. M54/74HCT devices are designed to directly inter2 face HSC MOS systems with TTL and NMOS components. They are also plug in replacements for LSTTL devices giving a reduction of power consumption. April 1993 HCT158 NC = No Internal Connection 1/11 M54/M74HCT157 M54/M74HCT158 CHIP CARRIER HCT157 HCT158 INPUT AND OUTPUT EQUIVALENT CIRCUIT PIN DESCRIPTION
(for HCT157) PIN No 1 2, 5, 11, 14 3, 6, 10, 13 4, 7, 9, 12 15 8 16 SYMBOL SELECT 1A to 4A 1B to 4B 1Y...
STMicroelectronics
