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SARA-G3 modules do not support the usage of two SIM at the same time, but two SIM can be
populated on the application board providing a proper switch to connect only the first or only the second
SIM per time to the SIM card interface of the SARA-G3 modules as described in
SARA-G3 modules do not support SIM hot insertion / removal: the module is able to properly use a SIM
only if the SIM / module physical connection is provided before the module boot and then held for
normal operation. Switching from one SIM to another one can only be properly done within one of these
two time periods:
after module switch-off by the AT+CPWROFF and before module switch-on by PWR_ON
after network deregistration by AT+COPS=2 and before module reset by AT+CFUN=16 or RESET_N
In the application circuit represented in
switch using its own GPIO before the module boot, to properly select the SIM that is used after the
module boot.
If the SIM detection feature is not required by the custom application, the related detection circuit
described in
Figure 46Figure 46
SIM_DET pin not connected.
The dual SIM connection circuit described in
well, providing proper connection between SIM switch and SIM chip as described in
If it is required to switch between more than two SIM, a circuit similar to the one described in
46Figure 46
can be implemented: for example, in case of four SIM circuit, using proper four-throw
switches instead of the suggested double-throw switches.
Follow these guidelines connecting the module to two SIM connectors implementing SIM presence detection:
Connect the contacts C1 (VCC) and C6 (VPP) of the two UICC / SIM to the VSIM pin of the
module by means of a proper low on resistance (i.e. few ohms) and low on capacitance (i.e. few
pF) double-throw analog switch (e.g. Fairchild FSA2567) to ensure high-speed data transfer
according to SIM requirements
Connect the contact C7 (I/O) of the two UICC / SIM to the SIM_IO pin of the module by means
of a proper low on resistance (i.e. few ohms) and low on capacitance (i.e. few pF) double-throw
analog switch (e.g. Fairchild FSA2567) to ensure high-speed data transfer according to SIM
requirements
Connect the contact C3 (CLK) of the two UICC / SIM to the SIM_CLK pin of the module by
means of a proper low on resistance (i.e. few ohms) and low on capacitance (i.e. few pF)
double-throw analog switch (e.g. Fairchild FSA2567) to ensure high-speed data transfer according to
SIM requirements
Connect the contact C2 (RST) of the two UICC / SIM to the SIM_RST pin of the module by
means of a proper low on resistance (i.e. few ohms) and low on capacitance (i.e. few pF)
double-throw analog switch (e.g. Fairchild FSA2567) to ensure high-speed data transfer according to
SIM requirements
Connect the contact C5 (GND) of the two UICC / SIM to ground
Connect one pin of the mechanical switch integrated in the two SIM connectors (e.g. the SW2 pins
as described in
Figure 46Figure
double-throw digital switch (e.g. NXP 74LVC1G157)
UBX-13000995 - R06
SARA-G3 series - System Integration Manual
Figure 46Figure
46, the application processor must drive the SIM
can be not implemented in the dual SIM connection circuit, leaving
Figure 46Figure 46
46) to the SIM_DET input pin of the module by means of a proper
Objective Specification
Figure 46Figure
can be implemented for SIM chips as
Figure 44Figure
Page 126 of 218
46.
44.
Figure
Design-in
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