Very small PDF, only 9.27 KB, holding datasheet information for the SN74LS399N, the N suffix indicating the plastic DIP package version. The 74LS399 is a quad two-input multiplexer with storage in the LS TTL family. Given the tiny size, the file may be a short summary rather than a full datasheet, so check that pinout and timing tables are present. Use it to identify pins, confirm supply connections and verify select and clock behaviour when diagnosing a faulty logic stage in vintage digital hardware.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @datasheet_technar_org. Enginerys does not host this file.
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