SARA-R4 series - System Integration Manual
UBX-16029218 - R06
Design-in
Page 60 of 102
Guidelines for single SIM card connection without detection
A removable SIM card placed in a SIM card holder has to be connected to the SIM card interface of SARA-R4
series modules as described in Figure 26, where the optional SIM detection feature is not implemented.
Follow these guidelines to connect the module to a SIM connector without 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.
Provide a 100 nF bypass capacitor (e.g. Murata GRM155R71C104K) on SIM supply line, close to the relative
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 relative pad of the SIM connector. ESD sensitivity rating of the
SIM interface pins is 1 kV (HBM). So that, according to 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 (27.7 ns is the
maximum allowed rise time on clock line, 1.0 µs is the maximum allowed rise time on data and reset lines).
SARA-R4 series
41
VSIM
39
SIM_IO
38
SIM_CLK
40
SIM_RST
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
D1 D2 D3 D4
C
8
C
4
Figure 26: Application circuits for the connection to a single removable SIM card, with SIM detection not 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, D2, D3, D4
Very Low Capacitance ESD Protection
PESD0402-140 - Tyco Electronics
J1
SIM Card Holder, 6 p, without card presence switch
Various manufacturers, as C707 10M006 136 2 - Amphenol
Table 21: Example of components for the connection to a single removable SIM card, with SIM detection not implemented