Datasheet in PDF format for the Texas Instruments SN74S158N, a quad 2-line-to-1-line data selector and multiplexer with inverted outputs from the Schottky TTL series, in N-suffix DIP packaging. The 24.5 KB size points to a short product document. Use it to map the select and strobe inputs and to check expected output states while debugging multiplexed address lines in older equipment. Do not confuse this part with the 157, which has non-inverted outputs, when you look for a substitute.
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