A logic datasheet numbered SDLS146, provided as a 309 KB PDF. The file name is uninformative about the part; the SDLS prefix denotes Texas Instruments standard logic literature, and the covered device is named in the header. Expect pinout, functional block or logic diagram, electrical characteristics and mechanical drawings. Technicians use it to locate supply pins, verify signal behaviour and select a replacement. Compare the logic family and package suffix on the actual component with the ordering table.
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.