Power and volume key page of the Samsung SM-A30S schematic, in a 4.29 MB PDF. It shows how the power button and volume up and down keys connect through the side key flex to the PMIC and processor. Repairers use it for phones that will not switch on from the button or have dead volume keys, tracing the key lines, checking pull-ups and finding ESD parts to test. Opens in any PDF reader; match the drawing to the actual board revision of the Galaxy A30s before trusting it.
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.