Specifications

SIM7912&SIM7906 Hardware Design V1.02
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DBG_ RXD
136
DI
P3
Receive data
1.8V power domain.
If unused, keep it open.
DBG_ TXD
137
DO
P3
Transmit data
PCM & I2C interface
Pin name
Pin
No.
Electrical description
Description
Comment
I2C_SCL
43
OD
I2C clock signal
1.8V power domain.
An external pull-up
resistor is required.
If unused, keep it open.
I2C_SDA
42
OD
I2C data signal
PCM_SYNC
65
DIO
P3
PCM synchronous signal
1.8V power domain.
In master mode, it is an
output signal.
In slave mode, it is an
input signal.
If unused, keep it open.
PCM_IN
66
DI
P3
PCM data input
1.8V power domain.
If unused, keep it open.
PCM_CLK
67
DO
P3
PCM clock output
1.8V power domain.
In master mode, it is an
output signal.
In slave mode, it is an
input signal.
If unused, keep it open.
PCM_OUT
68
DO
P3
PCM data output
1.8V power domain.
If unused, keep it open.
I2S_MCLK
152
DO
P3
I2S master clock output
Provide a digital clock
output for an external
audio codec.
If unused, keep it open.
ADC interface
Pin name
Pin
No.
Electrical description
Description
Comment
ADC0
173
AI
1.875V
Analog to digital
converter input0
If unused, keep it open.
ADC1
175
AI
1.875V
Analog to digital
converter input1
If unused, keep it open.
PCIe interface
Pin name
Pin
No.
Electrical description
Description
Comment
PCIe_REF
CLK_P
179
AIO
PCIe reference clock
plus
Required 90Ω differential
impedance
PCIe_REF
CLK_M
180
AIO
PCIe reference clock
minus
PCIe_TX_M
182
AO
PCIe transmit minus