A 56.5 KB datasheet in PDF form named SDNS016E, a document number whose E suffix probably reflects several revisions of the text. The file name carries no part number or manufacturer, so read the heading to see what it covers. Brief datasheets like this are mainly consulted for pinout, logic function and electrical limits, which are what you need to probe a small IC on a board and confirm a correct replacement before soldering.
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.
Any PDF readerSumatraPDFFirefox / ChromeFlexBV (links PDF to boardview)