PDF document of 609 KB whose name points to the KBC1122, a keyboard and embedded controller chip from SMSC (now Microchip) used on many laptop motherboards. Although catalogued as a schematic, it is most likely the chip datasheet or a reference sheet covering pinout and functions. Technicians use such material to identify power, clock and reset pins, check the SPI interface to the BIOS flash and confirm the controller is alive when a board will not power on. Open it in any PDF viewer and compare the package markings with your chip.
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 @laptop_bios_schematic. 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.