Audio Interfaces - Quectel SC20-WL Hardware Design

3.21. Audio Interfaces

SC20-WL module provides two analog input channels and three analog output channels. The following
table shows the pin definition.
Table 22: Pin Definition of Audio Interfaces
Pin Name Pin No
MIC1P 4
MIC_GND 5
MIC2P 6
EARP 8
EARN 9
SPKP 10
SPKN 11
HPH_R 136
HPH_GND 137
HPH_L 138
HS_DET 139

The module offers two audio input channels which are both single-ended channels.

The earpiece interface uses differential output.

The loudspeaker interface uses differential output as well. The output channel is available with a
Class-D amplifier whose output power is 879mW when VBAT is 4.2V and load is 8Ω.

The headphone interface features stereo left and right channel output, and headphone insert
detection function is supported.
SC20-WL_Hardware_Design
I/O Description
AI Microphone positive input for channel 1
MIC reference ground
AI Microphone positive input for channel 2
AO Earpiece positive output
AO Earpiece negative output
AO Speaker positive output
AO Speaker negative output
AO Headphone right channel output
Headphone virtual ground
AO Headphone left channel output
AI Headset insertion detection
Smart Wi-Fi Module Series
SC20-WL Hardware Design
Comment
High level by default
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