Ublox TOBY-L2 series, System Integration Manual

Page: 99 / 164

TOBY-L2 and MPCI-L2 series - System Integration Manual
UBX-13004618 - R28 Design-in Page 99 of 164
Guidelines for single SIM card connection with detection
A removable SIM card placed in a SIM card holder must be connected to the SIM card interface of
TOBY-L2 modules as described in
Figure 52 , where the optional SIM card detection feature is
implemented.
Follow these guidelines to connect the module to a SIM connector with SIM presence detection:

Connect the UICC / SIM contacts 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 described in
Figure 52 ) 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 described in
Figure 52 ) 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 52 .
 Provide a weak (e.g. 470 k  ) pull-down resistor at SIM detection line, as R2 resistor in Figure 52
 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 in case
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, higher protection level can be required if the lines are externally accessible
on the application device.
 Limit capacitance and series resistance on each SIM signal to match the SIM requirements
(26.2 ns max allowed rise time on clock line, 1.0
µ
s max allowed rise time on data and reset lines).
TOBY-L2 series
5
V_INT
60 GPIO5
SIM CARD
HOLDER
C
5
C
6
C
7
C
1
C
2
C
3
SIM Card
Bottom View
(contacts side)
C1
VPP (C6)
VCC (C1)
IO (C7)
CLK (C3)
RST (C2)
GND (C5)
C2 C3 C5
J1
C4
SW1
SW2
D1 D2 D3 D4 D5 D6
R2
R1
C
8
C
4
TP
59
VSIM
57
SIM_IO
56
SIM_CLK
58
SIM_RST
Figure 52: Application circuit for the connection to a single removable SIM card, with SIM detection implemented
Reference Description Part Number – Manufacturer
C1, C2, C3, C4 47 pF Capacitor Ceramic C0G 0402 5% 50 V GRM1555C1H470JA01 – Murata
C5 100 nF Capacitor Ceramic X7R 0402 10% 16 V GRM155R71C104KA01 – Murata
D1, … , D6 Very Low Capacitance ESD Protection PESD0402-140 – Tyco Electronics
R1
1 k  Resistor 0402 5% 0.1 W
RC0402JR-071KL – Yageo Phycomp
R2 470 k  Resistor 0402 5% 0.1 W RC0402JR-07470KL- Yageo Phycomp
J1 SIM Card Holder, 6 + 2 p, with card presence switch Various manufacturers, as CCM03-3013LFT R102 – C&K
Table 32: Example of components for the connection to a single removable SIM card, with SIM detection implemented