Sim Card Application - SimCom SIM808 Hardware Design

4.10.1 SIM Card Application

Table 17: SIM pin definition
Name Pin
SIM_VDD 29
SIM_DATA 30
SIM_CLK 31
SIM_RST 32
SIM_PRE 33
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.
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.
SIM808_Hardware Design_V1.00
function
Voltage supply for SIM card. Support 1.8V or 3V SIM card
SIM data input/output
SIM clock
SIM reset
SIM card detection
Figure 36: Reference circuit of the 8-pin SIM card holder
Figure 37: Reference circuit of the 6-pin SIM card holder
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Smart Machine Smart Decision
2014.03.27