A 300 KB datasheet in PDF format named SDLS174, a code that does not state the component it documents. The SDLS prefix matches Texas Instruments literature numbering for standard logic parts, so the device is probably a logic IC confirmed on the cover page. Contents should include the pinout, truth table, electrical characteristics and package information. Use it for in-circuit checks of input and output states, for verifying supply voltage at the right pin, and for confirming pin compatibility before 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.
How to open a .pdf file
The standard format for schematics, block diagrams, power-sequence charts and service manuals.