Smart LTE Module Series
Smart EVB User Guide
Smart_ EVB_User_Guide
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Table 6: Pin Assignment of Headphone Interface
The following figure shows the sketch design of audio plug which suits for the audio jack on Smart EVB.
2
1
MIC
GND
SW
SPK_R
SPK_L
3
4
32
Ω
32
Ω
HS_DET
5
Figure 20: Sketch of Audio Plug
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.
Pin No.
Pin Name
Description
1
MIC
Positive microphone input
2
GND
Dedicated GND for audio
3
R-AUDIO
Headphone right channel
4
DETECT
Headphone detection
5
L-AUDIO
Headphone left channel
6
GND
Dedicated GND for audio
