Smart Machine Smart Decision
4.10.1
SIM Card Application
Table 17: SIM pin definition
Name
Pin
function
SIM_VDD
29
Voltage supply for SIM card. Support 1.8V or 3V SIM card
SIM_DATA
30
SIM data input/output
SIM_CLK
31
SIM clock
SIM_RST
32
SIM reset
SIM_PRE
33
SIM card detection
It is recommended to use an ESD protection component such as ON (http://onsemi.com ) SMF12CT1G.
Note that
the SIM peripheral circuit should be close to the SIM card socket. The reference circuit of the 8-pin SIM card
holder is illustrated in the following figure.
Figure 36: Reference circuit of the 8-pin SIM card holder
The SIM_PRESENCE pin is used for detection of the SIM card hot plug in. User can select the 8-pin SIM card
holder to implement SIM card detection function. AT command “AT+CSDT” is used to enable or disable SIM
card detection function. For details of this AT command, please refer to
document [1]
.
If the SIM card detection function is not used,
user can keep the SIM_PRESENCE pin open. The reference
circuit of 6-pin SIM card holder is illustrated in the following figure.
Figure 37: Reference circuit of the 6-pin SIM card holder
SIM808_Hardware Design_V1.00 2014.03.27
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