SIM card circuit page from the Samsung SM-A30S (Galaxy A30s) schematic set, saved as a 4.29 MB PDF. It shows the SIM tray connector and the lines feeding it, typically the supply, clock, reset and data, plus their protection parts. Technicians consult it when the phone reports no SIM or drops the card, measuring the SIM voltage and checking for damaged ESD diodes or broken traces. Any PDF reader opens it; compare part locations with the board you are working on.
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.