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Carrier Board Design Guide for SOM-9X35 Module
19
PIN#
PIN Name
GPIO#
Voltage
Level
Power
Domain
I/O
Reset
Assignment
Function
J2.6
ACCDET
MT6390/
MT6357
ACCDET
2.8V
AVDD28_
MIC
AI
ACCDET
Earphone MIC,
ACCDET
J2.7
USB_DM_P0 MT8365
USB_DM_P0
3.3V
AVDD33_
USB
AIO
USB_DM_P0 1st USB2.0 OTG D-
J2.8
AU_VIN0_N
MT6390/
MT6357
AU_VIN0_N
2.8V
AVDD28_
MIC
AI
AU_VIN0_N
On board MIC,
Differential MIC0-
input,
J2.9
USB_DP_P0 MT8365
USB_DP_P0
3.3V
AVDD33_
USB
AIO
USB_DP_P0 1st USB2.0 OTG D+
J2.10 AU_VIN0_P
MT6390/
MT6357
AU_VIN0_P
2.8V
AVDD28_
MIC
AI
AU_VIN0_P
On board MIC,
differential MIC0+
input, need Vbias on
carrier board
J2.11
GND_SIGNAL Ground
Power
Ground
SIGNAL Ground
J2.12 AVSS28_AUD
MT6390/
MT6357
AVSS28_AUD
AIO
AVSS28_AUD
Audio analog ground,
add a 0 Ohm resistor
to ground (Carrier
board)
J2.13
USBOTG_
VBUS
USBOTG_
VBUS
5V
USBOTG_
VBUS
Power
USBOTG_
VBUS
1st USB2.0 OTG VBUS
power for detect
J2.14
AU_HPR
MT6390/
MT6357
AU_HPR
2.8V
AVDD28_
AUD
AO
AU_HPR
Headphone audio
right channel output
J2.15
USBOTG_ID
MT8365
EINT23/
GPIO23/
KPROW1/
I0:IDDIG/
O:WIFI_TXD/
O*CLKM3
1.8V
DVDD18_
IO1
I, PD
IDDIG
1st USB2.0 OTG ID
input, High: device,
Low: Host
J2.16
AU_HPL
MT6390
AU_HPL
AO
AU_HPL
Headphone audio left
channel output
J2.17
USBOTG_
DRVVBUS
MT8365
EINT25/
GPIO25/
B1:KPCOL1/
O:USB_
DRVVBUS
1.8V
VDD18_IO1 I, PD
USBOTG_
DRVVBUS
1st USB2.0 OTG
DRVVBUS output,
High active
J2.18
GND_SIGNAL Ground
Power
Ground
SIGNAL Ground
J2.19
GND_SIGNAL Ground
Power
Ground
SIGNAL Ground
J2.20
EXT_GPIO3
MT8365
EINT130/
GPIO130/
O*TDM_
TX_LRCK/
O*I2S3_LRCK
1.8V
DVDD18_
IO1
I, PD
EXT_GPIO3
MT8365 GPIO130,
default for SPI_BUSY,
input, high active
J2.21
CS_N
MT6390/
MT6357
CS_N
0~4.2V
Vbattery
AI
CS_N
Battery Gas Gauge
CS_N