Quectel SC20-WL Hardware Design page 23

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
USB Interface
Pin Name Pin No.
USB_VBUS 141, 142
USB_DM 13
USB_DP 14
USB_ID 16
UART Interfaces
Pin Name Pin No.
SC20-WL_Hardware_Design
I/O Description
Microphone positive
AI
input for channel 1
MIC reference
ground
Microphone positive
AI
input for channel 2
Earpiece positive
AO
output
Earpiece negative
AO
output
Speaker positive
AO
output
Speaker negative
AO
output
Headphone right
AO
channel output
Headphone virtual
ground
Headphone left
AO
channel output
Headset insertion
AI
detection
I/O Description
PI USB power supply
USB differential data
IO
bus (minus)
USB differential data
IO
bus (plus)
AI USB ID detection
I/O Description
Smart Wi-Fi Module Series
SC20-WL Hardware Design
DC
Comment
Characteristics
High level by
default.
DC
Comment
Characteristics
Vmax=6.3V Used for USB 5V
Vmin=4.35V power input and
Vnorm=5.0V USB detection.
Compliant with
Require differential
USB 2.0 standard
impedance of 90Ω.
specification.
High level by
default.
DC
Comment
Characteristics
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