Texas Instruments BQ24730 datasheet, 4.13 MB in PDF, filed under schematics; the name gives only the part number. This controller family handles battery charging and adapter/battery selection in many laptops. The document is useful for pin functions, the reference design, the regulation thresholds and the external components around the IC, which helps when tracing a no-charge or no-power fault from the DC jack. Any PDF reader opens it. Check the chip marking and package against the datasheet before probing pins.
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 @laptopbios21. 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.