Schematic for the Xiaomi Poco M3 smartphone, with J19S MB marking the main board, distributed as a ZIP of about 3.16 MB. J19S is Xiaomi's internal project code shared with closely related Redmi models. The diagrams cover power management, charging, baseband and peripheral connections and help a technician measure rails, isolate a short or confirm connector pinouts. Open the contained pages in a PDF reader, and check that the main board carries the same project marking before trusting component 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 @mischematic. Enginerys does not host this file.
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