Datasheet covering the SN74157N, a quad 2-line to 1-line data selector and multiplexer in a plastic DIP package, provided as a 20.5 KB PDF. Inside are the pinout, select and strobe function table, switching times and electrical limits. A technician uses it to verify which input is routed to each output while probing select and enable lines on bus-switching or video-memory circuits. Confirm the logic family on the chip, such as standard, LS or HC, since thresholds differ.
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