PDF reference for the SN7405N, a hex inverter from the 7400 TTL family with open-collector outputs, supplied in plastic DIP. Open-collector stages allow wired-AND connections and require pull-up resistors, so faults on shared lines can come from any device tied to them. The roughly 22 KB sheet provides pin assignment, supply limits and output characteristics useful during bench diagnosis with a logic probe or oscilloscope. Check that the printed part number matches before relying on the values given.
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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