Reference Circuit Design For Microphone Interface - Quectel SC20 Series Hardware Design

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 879 mW when VBAT is 4.2 V and load is 8 Ω.
The headphone interface features stereo left and right channel output, and supports headphone

insertion detect.

3.22.1. Reference Circuit Design for Microphone Interface

Figure 26: Reference Circuit Design for Microphone Interface
SC20_Series_Hardware_Design
AO Speaker output (+)
AO Speaker output (-)
AO Headphone right channel output
AI Headphone reference ground
AO Headphone left channel output
AI Headset hot-plug detect
Smart Module Series
High level by default.
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