A 72.5 KB PDF identified only by the code 45L and indexed under schematics, with no device, brand or revision stated. The name is uninformative on its own and likely refers to a component or part series related to the 45L-D file. Check the title page in any PDF reader to see what it actually contains. If it proves to be a datasheet, use it for pinout, package and rating checks; in all cases verify the marking on the physical part first.
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 @cyberlanelectonik. 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)