Datasheet for the RT9179A, an integrated circuit made by Richtek, provided as a 267 KB PDF. The name gives only the part number, so consult the document itself for the exact function, package options and ratings. Repair technicians use datasheets like this to identify a part by its marking, read the pinout, find which pins carry input, output and enable signals, and check the typical application circuit when diagnosing a missing rail or a shorted component. Confirm the package and marking code on the board match the variant described.
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 @ic_mosfet_pdf_datasheets. 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.