Smart Machine Smart Decision
15
3.
SPI: supports master-only mode; up to 52 MHz.
Secure Digital Interface
SIM8905A provides one 4-bit secure digital interface, which supports the following standards:
SD Specifications Part 1 Physical Layer Specification Version 3.00
Part A2 SD Host Controller Standard Specification Version 3.00
Part E1 SDIO Specification Version 3.00
1 DAT2
2 DAT3
3 CMD
4 VDD
5 CLK
6 VSS
7 DAT0
8 DAT1
11 GND
12 GND
13 GND
14 GND
9 DET_SW
10 COMMON
SD Card
SD_DATA2
SD_DATA3
SD_CMD
SD_LDO11
SD_CLK
SD_DATA0
SD_DATA1
1M
SD_DET
LDO5_1V8
Module
1uF
33pF
TVS
C<15pF
Placed close to SD card
33R
33R is required for high-speed operation;
placed close to the module
NM
NM
NM
NM
NM
1uF
SD_LDO12
NM
：
Not Mounting
Reserved
Figure17: SD card reference circuit
Display Interface
SIM8905A provides a 4-lane MIPI_DSI, with 1.5 Gbps per lane high-speed mode bandwidth, to support 720p HD
display.
PWM is used as PWM control for external WLED driver.
Table 5: Display interface pin definitions
Pin Name
Pin#
Type
Description
PWM
29
O
PWM control for external WLED driver
LCD_RST_N
49
O
LCD reset
LCD_TE
50
I
LCD tear effect
MIPI_DSI_CLK_M
52
O
MIPI display serial interface
MIPI_DSI_CLK_P
53
O
MIPI_DSI_LANE0M
54
O
MIPI_DSI_LANE0P
55
O
MIPI_DSI_LANE1M
56
O
MIPI_DSI_LANE1P
57
O
