PDF datasheet of 410 KB carrying only a Texas Instruments SDLS document number instead of a part name; TI applies this prefix to datasheets for its classic bipolar logic families. The exact device has to be identified from the first page. Logic datasheets like this are used for pin identification, truth tables, fan-out limits and delay figures when tracing faults on older digital boards or choosing a compatible replacement. Before relying on the data, make sure the chip marking and package code agree with the document.
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.