Quectel EG21-G Reference Design page 18

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D
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Notes:
1. The analog output only drives earphone and headset. For larger power loads such as speakers, an audio power amplifier should be added in the design.
2. In handset application, both the MIC and SPK signal traces need to be routed as differential pairs.
3. In earphone application, the MIC signal traces need to be routed as differential pairs.
4. All MIC and SPK signal traces should be routed with total grounding and far away from noise such as clock and DC-DC signals, etc.
5. ALC5616 and TLV320AIC3104 cannot be used simultaneously in audio codec design.
A
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5
[7,8,9] MIC_P
[7,8,9] MIC_N
[7,8]
SPK_P
[7,8]
SPK_N
[7,8,9] MIC_N
R0701
R0702
[7,8,9] MIC_P
[7,8]
SPK_L
[7,8]
SPK_R
10pF 33pF 10pF 33pF
5
4
4 3
Audio Interfaces
Handset Application
10pF 33pF
10pF 33pF 10pF 33pF
ESD9X5.0ST5G F0701
F0702
F0703
F0704
10pF 33pF 10pF 33pF 10pF 33pF
PESD5V0S1BL
Earphone Application
Close to earphone interface
C0713 C0715
C0714
10pF 33pF 4.7μF
0R
J0702
NM_0R
2
4
5
3
1
R0704
0R
10pF 33pF
R0705
NM_0R
3
2
0R
4
0R
1
0R
3
0R
2
J0701
CTIA OMTP
R0702/R0705 M
NM
R0701/R0704 NM
M
R0703 0R
[7,8,9] R-0805
MIC_P
Quectel Wireless Solutions
DRAWN BY
Lorry XU
CHECKED BY
Woody WU
SHEET
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1
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PROJECT TITLE
EG21-G Reference Design
VER
SIZE
A2 1.0
9 OF 14 DATE 2019/12/5
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