Specifications

SIM7912&SIM7906 Hardware Design V1.02
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3.12
SPI Interface
Module provides one SPI interface multiplexed from BT UART interface. The interface only supports
master mode with a maximum clock frequency up to 50MHz.
The following table shows the pin definition of SPI interface.
Table 27: Definition of SPI interface
Pin name
Pin no.
I/O
Functional description
Comment
BT_CTS
164
DO
Can be multiplexed into SPI_CLK.
1.8V power domain
BT_ RTS
166
DI
Can be multiplexed into SPI_CS.
BT_ TXD
163
DO
Can be multiplexed into SPI_MOSI.
BT_ RXD
165
DI
Can be multiplexed into SPI_MISO.
The following figure shows the reference circuit of SPI interface.
Module
SPI_MOSI
SPI device
DI
CLK
SPI_CLK
SPI_MISO
CS
VDD_EXT
10K
SPI_CS_N
DO
Figure 26: SPI reference circuit
3.13 ADC Interface
Module supports two 15bits ADC interfaces. Its performance parameters are shown as follow:
Table 28: Definition of ADC interface
Pin name
Pin no.
I/O
Functional description
Comment
ADC0
173
AI
Input Voltage Range:
0~1.875V
General purpose analog
to digital converter
interface.