Mic And Speaker - Quectel SC20-CE User Manual

4 DETECT
5 L-AUDIO
6 GND
The following figure shows the sketch of audio jack which matches the Smart EVB.

3.3.3. MIC and Speaker

SMT U701 MIC is used for microphone and speaker is soldered on TP703 and TP704. The following
figure shows the schematic of the MIC and Speaker.
Smart_EVB_User_Guide
4
3
GND
2
1
SW
Figure 10: The Sketch of Audio Jack
EVB
100pF
FB
MIC1_P
MIC1_N
EAR_P
EAR_N
100 pF
Figure 11: MIC and Speaker Circuit
Confidential / Released
Earphone detection
Earphone left channel
Dedicated GND for audio
SPK_R
32Ω
MIC
ESD ESD
33pF 33pF
HPH_L
TP703
HPH_R
TP704
ESD ESD
33pF 33pF
LTE Module Series
Smart EVB User Guide
SPK_L
32Ω
U701 MIC
REC
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