M12 Hardware Design
M12_Hardware_Design_V3.3
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Table 23: Pin name of the SD card and T-Flash(Micro SD) card
In SD card interface designing, in order to ensure good communication performance with SD card,
please follow the design principles below:
Keep all the SD card lines far away from VBAT power and RF trace.
Route all SD card signals as short as possible. Ensure the length of every trace does not
exceed 10cm.
The SD_CLK and SD_DATA and SD_CMD trace should be routed together. Keep trace
difference of SD_DATA, SD_CMD and SD_CLK to be less than 10mm.
In order to ensure good ESD protection, it is recommended to add TVS on signal pins with
the capacitance less than 15pF.
Reserve external pull-up resistor for other data lines except the DATA0 signal.
The SD_CLK and SD_DATA line must be shielded by ground in order to improve EMI.
Pin No.
Pin name of SD card
Pin name of T-Flash(Micro SD) card
1
CD/DATA3
DATA2
2
CMD
CD/DATA3
3
VSS1
CMD
4
VDD
VDD
5
CLK
CLK
6
VSS2
VSS
7
DATA0
DATA0
8
DATA1
DATA1
9
DATA2
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