Display circuitry of the Samsung Galaxy A12 (SM-A12) in a 3.40 MB PDF schematic. It covers the LCD connector, panel supply rails and the display interface toward the processor, which is the starting point when the screen stays black, shows lines or flickers while the phone otherwise works. Measure the panel voltages at the connector and inspect the filters before blaming the processor. Backlight is documented in a separate file in this set. The model suffix and board revision are not named, so confirm them on the unit.
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 @phoneSchematics. 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.