PDF schematic page for the 2 MP depth rear camera of a handset, part of a sectioned series of roughly 4.77 MB pages; the device model is not named. It typically details the depth sensor connector, data and control lines and its supply voltages. Technicians consult it when portrait or blur modes fail or the camera app reports an error linked to the secondary sensor. Measure the supplies at the connector and look for shorted capacitors, after confirming the drawing matches your phone.
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.