User's Manual

Smart Machine Smart Decision
SIM7100A_User Manual_V1.01 2014-12-11
45
3.7.2 SDIO Interface Pin Description
Table 24: SDIO Pin description
Table 25: SDIO Electronic characteristic
Symbol Parameter
Min Typ Max Unit
V
IH
High-level input voltage
1.26 1.8 2.1 V
V
IL
Low-level input voltage
-0.3 0 0.63 V
V
OH
High-level output voltage
1.35 - 1.8 V
V
OL
Low-level output voltage
0 0 0.45 V
3.7.3 SD Design guide
The module can’t provide power for SD card. External 2.85V LDO is needed with capable of 300mA.
Data lines should be pulled up to VDD_EXT by 10K resistors. ESD/EMI components should be arranged
beside SD card socket. Refer to the following application circuit.
Figure 28: SD interface circuit
Pin name Pin No. Function
KBR2 30 SD2_DATA0
KBC1 27 SD2_DATA1
KBC0 28 SD2_DATA2
KBC2 31 SD2_DATA3
KBR0 29 SD2_CMD
KBC3 32 SD2_CLK