STMicroelectronics M74HCT157 Manuals

The document introduces the M74HCT157, which is a high-speed CMOS quad 2-input digital multiplexer. It features high speed, low power dissipation, compatibility with TTL outputs, etc. The device consists of four 2-input digital multiplexers with common select and strobe inputs. When the STROBE input is held high, data selection is inhibited and all the outputs become low. 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.

M54/74HCT157/158 are high speed CMOS QUAD 2-CHANNEL MULTI- PLEXERs fabricated with silicon gate C2MOS technology. They achieve the high speed operation similar to equivalent LSTTL while maintaining the CMOS low power dissipation. 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 theM74HCT158. 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.