This part is a kind of semiconductor called 74157.

Function of this product has Quad 2-Line to 1-Line Data Selectors/Multiplexers.

Manufacturers : National Semiconductor

Image and pinout :

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54157 DM54157 DM74157 Quad 2-Line to 1-Line Data Selectors Multiplexers June 1989 54157 DM54157 DM74157 Quad 2-Line to 1-Line Data Selectors Multiplexers General Description These data selectors multiplexers contain inverters and drivers to supply full on-chip data selection to the four output gates A separate strobe input is provided A 4-bit word is selected from one of two sources and is routed to the four outputs Features Y Y Y Y Applications Y Y Y Buffered inputs and outputs Typical propagation time 9 ns Typical power dissipation 150 mW Alternate Military Aerospace device (54157) is available Contact a National Semiconductor Sales Office Distributor for specifications Y Expand any data input point Multiplex dual data buses Generate four functions of two variables (one variable i [ ... ]

74157 PDF Datasheet Download