Schematic diagram and service manual for the Xiaomi Redmi 4A smartphone, in a 2.44 MB RAR archive despite being listed under firmware. A repair technician uses such documents to trace power lines from the PMIC, follow charging, display and audio circuits, and find component positions for board-level repair. The contents are usually PDF files that open in any reader. Check that the hardware revision in the documents matches the phone on your bench.
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 @schematic_mobile5. Enginerys does not host this file.
How to open a .rar file
Compressed archive — the usual wrapper for a schematic + boardview pair or a BIOS + EC set.
Back up your own chip before writing any dump, and match the full board number and revision. Flashing guide →