PDF datasheet of 536 KB, identified only as SDLS197. No device name appears in the file name, although the code style matches Texas Instruments logic documentation, so the covered part must be confirmed on opening. Such a sheet typically lists pin functions, a function table, operating conditions and switching characteristics. It supports checking a logic IC in circuit, locating supply and ground pins, and judging a substitute part. Verify the chip marking and package before relying on the pin numbers.
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.
How to open a .pdf file
The standard format for schematics, block diagrams, power-sequence charts and service manuals.