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WM_PRJ_Q24NG_PTS_002-001 June
2006
3.2.6.3 SIM 3 V / 5 V management
It is possible to detect and manage 3 V and 5 V SIM cards using an
external level shifter device (see Figure below).
In this case, depending on the type of SIM detected, the module firmware
triggers the GPO0 output signal (pin #26) in order to properly set the
external SIM driver level (3 V or 5 V).
As for 3 V SIM, it is recommended to add Transient Voltage Suppressors
on the signals connected to the SIM socket (refer to Figure 10).
Typical implementation:
Figure 10: 3 V / 5 V SIM interface implementation example
