Audio schematic for the Samsung SM-A23 covering the microphone, loudspeaker and earpiece circuits, packed into a 2.79 MB PDF. It lets you follow mic bias, speaker amplifier outputs and the earpiece lines from their connectors back to the audio codec. Typical uses include faults such as no sound on calls, a dead loudspeaker or the other party not hearing the caller. Open it in any PDF reader and confirm the board revision corresponds to your unit before trusting designators and test points.
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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