Listed as a schematic, this 55.7 KB PDF is named only 61cnq, a truncated code without suffix, model, brand or board revision. It likely covers a series of related components rather than a single part. The small size suggests a brief reference sheet with pin layout and ratings. Any PDF viewer will open it. Read the full marking on the component you are working on, since the missing suffix may correspond to different voltage or current grades within the series.
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.