Specifications

SIM7912&SIM7906 Hardware Design V1.02
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Audio layout guidelines：
Analog input:
 0.2mm trace widths; 0.2mm spacing between traces.
 Pseudo differential route for MIC.
 Isolate from noise sources, such as antenna, RF signals, SMPS, clocks, and other high-speed
signals.
Analog output:
 Isolate from noise sources such as antenna, RF signals, SMPS, clocks, and other digital signals
with fast transients.
 Speaker output signal – route as differential pair with 0.5mm trace widths.
3.10 I2C Interface
Module supports one I2C interfaces, meet I2C specification version 5.0, and data rate up to 400 Kbps.
The following figure shows the I2C bus reference circuit.
Module
I2C_SDA
I2C device
SDA
GNDGND
I2C_SCL
SCL
VDD_EXT
2.2K 2.2K
Figure 22: I2C reference circuit
Table 25: Definition of I2C interface
Pin name
Pin no.
I/O
Functional description
Comment
I2C_SCL
43
OD
I2C serial clock
I2C default use for codec
Pull up to VDD_EXT
externally
If unused, keep it open.
I2C_SDA
42
OD
I2C serial data