Microphone And Earphone Interfaces - Quectel Smart EVB User Manual

Table 6: Pin Assignment of Headphone Interface
Pin No. Pin Name
1 MIC
2 GND
3 R-AUDIO
4 DETECT
5 L-AUDIO
6 GND
The following figure shows the sketch design of audio plug which suits for the audio jack on Smart EVB.

3.7.3. Microphone and Earphone Interfaces

Smart EVB provides a microphone interface and an earphone interface. The following figure shows the
reference circuit design for microphone and earphone interfaces.
Smart_ EVB_User_Guide
Description
Positive microphone input
Dedicated GND for audio
Headphone right channel
Headphone detection
Headphone left channel
Dedicated GND for audio
5
4
3
GND
2
1
SW
Figure 20: Sketch of Audio Plug
Smart LTE Module Series
Smart EVB User Guide
HS_DET
SPK_L
32Ω
SPK_R
32Ω
MIC
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