Schematic package for the I8552, a 4.16 MB zip archive; the code matches Samsung's Galaxy Win Duos, though the listing gives no brand. No board revision is stated, so check the title blocks inside for the version. Schematics like these are read in a PDF viewer to trace battery and charging rails, follow dual-SIM, display and keypad signals, and locate components for checking a short or a missing voltage. Compare the main board marking on the handset with the drawings before using reference designators.
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 @esquematicosparatodos. Enginerys does not host this file.
How to open a .zip file
Compressed archive that every operating system opens without extra software.