LEXI-R422 - System integration manual
UBX-23007449 - R02
Design-in
Page 66 of 108
C1-Public
2.5.1.2
Guidelines for single SIM card connection without detection
A removable SIM card placed in a SIM card holder must be connected to the SIM card interface of
LEXI-R422 modules as described in
, 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 (50 ns
is the maximum allowed rise time on clock line, 1.0 µs is the maximum allowed rise time on data
and reset lines).
LEXI-R422
H15
VSIM
J15
SIM_IO
K15
SIM_CLK
L15
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 43: 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 positions, without card presence switch
Generic manufacturer,
as C707 10M006 136 2 - Amphenol
Table 27: Example of components for the connection to a single removable SIM card, with SIM detection not implemented
