PDF datasheet for the SN7400N, the quad 2-input positive NAND gate that started the 7400 TTL series, in a plastic DIP package. About 14 KB in size, it gives pinout, truth behaviour and basic electrical ratings. Technicians servicing vintage computers, test gear or control boards use it to locate VCC on pin 14 and ground on pin 7 and to verify each gate's output with a logic probe. Confirm the chip marking matches this device before using it as a reference for replacement.
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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