An 826 KB PDF from Texas Instruments labelled with literature code SDLS134. The larger size suggests a longer or multi-device logic datasheet, but the name does not identify the part, so check the front page. The SDLS series belongs to TI's legacy TTL catalog. Such sheets give pinouts, logic diagrams, electrical limits and timing waveforms used for probing and replacing chips on older boards. Verify that the part marking on the PCB matches before use.
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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