Filed under schematics at 212 KB, the PDF named 20ETF-S gives no device, board or revision details. Its code is part of a series that also appears here with HV, FP and 08 suffixes, so check which variant it actually covers. Any PDF viewer opens it. A reference like this is used to confirm pinout, package outline and limits when you test a suspect part or choose a replacement. Compare the full code on the original part before you rely on it, since variants are not always equivalent.
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.