PDF schematic extract for the Samsung SM-A20S showing the SIM card circuit, 4.63 MB in size. It details the SIM tray connector, the clock, data and reset lines, card supply voltage and the ESD protection components along the path. Technicians reach for this page when the phone reports no SIM, the card is detected intermittently, or a socket must be replaced after corrosion. Check continuity from connector pins to the processor side and compare with the board you have, since regional variants can differ slightly.
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.
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