PDF datasheet of 692 KB named only SDLS191, a literature code that tells nothing about the exact component inside. Texas Instruments uses the SDLS prefix for documents on its standard logic lines, so treat this as a likely logic IC reference and verify the part on page one. Such sheets list recommended operating conditions, propagation delays and absolute maximum ratings. Use them to judge whether a chip is being driven outside its limits and to confirm pin 1 orientation before soldering a 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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The standard format for schematics, block diagrams, power-sequence charts and service manuals.