Pin | Pin Name |
Description |
1 | Left | audio channel (tip) |
2 | Right | audio channel (1st ring) |
3 | Microphone | input channel (2nd ring) |
4 | Ground | Common ground |
If 3-pin 2.5 mm standard headphone headset detected, the pinout is following: pin 1 (tip) - mic, pin 2 - earbud, pin 3 - ground.