PDF of 6.04 MB named only after a website address, so it carries no device model, brand or board number. Its catalogue type is schematic, but the actual contents have to be checked by opening it in any PDF reader. If it is a board schematic, read the title block for the model and revision, and compare them with the markings on the PCB. Only then use it to trace power rails or the circuitry around a faulty component. Treat it as unidentified material until verified.
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 @mobile_jump2. 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.