Datasheet for the AO3401 P-channel MOSFET, the name stating minus 30 V and minus 4 A ratings, filed under schematics as a 498 KB PDF. The AO prefix points to Alpha and Omega Semiconductor, and the part is a small SOT-23 device often used for load switching and power path control on laptop and phone boards. The document should show gate threshold, on-resistance and pinout. Use it to identify gate, source and drain when checking a shorted rail or replacing a failed switch, and confirm the marking code on the package.
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.