Integration Manual

TSD-19090601 - R15 Contents Page 92 of 143
Guidelines for single SIM card connection with detection
If the optional SIM card detection feature is required by the application, then a removable SIM card placed
in a SIM card holder must be connected to the SIM0 interface of TOBY-L3 series modules as shown in
Figure 26:
Follow these guidelines to connect the module to a SIM connector implementing SIM detection:
 Connect the UICC / SIM contact C1 (VCC) to the VSIM pin of the module.
 Connect the UICC / SIM contact C7 (I/O) to the SIM_IO pin of the module.
 Connect the UICC / SIM contact C3 (CLK) to the SIM_CLK pin of the module.
 Connect the UICC / SIM contact C2 (RST) to the SIM_RST pin of the module.
 Connect the UICC / SIM contact C5 (GND) to ground.
 Connect one pin of the normally-open mechanical switch integrated in the SIM connector (e.g. the SW2
pin as shown in Figure 26) to the GPIO5 input pin of the module.
 Connect the other pin of the normally-open mechanical switch integrated in the SIM connector (e.g. the
SW1 pin as shown in Figure 26) to the V_INT 1.8 V supply output of the module by means of a strong
(e.g. 1 k) pull-up resistor, as the R1 resistor in Figure 26.
 Provide a weak (e.g. 470 k) pull-down at the SIM detection line, as the R2 resistor in Figure 26.
 Provide a 100 nF bypass capacitor (e.g. Murata GRM155R71C104K) at the SIM supply line, close to the
related pad of the SIM connector, to prevent digital noise.
 Provide a bypass capacitor of about 22 pF to 47 pF (e.g. Murata GRM1555C1H470J) on each SIM line,
very close to each related pad of the SIM connector, to prevent RF coupling especially when the RF
antenna is placed closer than 10 - 30 cm from the SIM card holder.
 Provide a very low capacitance (i.e. less than 10 pF) ESD protection (e.g. Tyco PESD0402-140) on each
externally accessible SIM line, close to each related pad of the SIM connector: ESD sensitivity rating of
the SIM interface pins is 1 kV (HBM), so that, according to the EMC/ESD requirements of the custom
application, a higher protection level can be required if the lines are externally accessible on the
application device.
 Limit the capacitance and series resistance on each SIM signal to match the SIM requirements (23 ns is
the max rise time on the clock line, 1.0 µs is the max rise time on the data and reset lines).