SARA-N2 / N3 series - System integration manual
UBX-17005143 - R13
Design-in
Page 56 of 95
C1-Public
Guidelines for SIM card connection
An application circuit for the connection to a removable SIM card placed in a SIM card holder is
described in
Follow these guidelines connecting the module to a SIM connector:
•
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.
•
Provide a 100 nF bypass capacitor (e.g. Murata GRM155R71C104K) at the SIM supply line (
VSIM
),
close to the related pad of the SIM connector, to prevent digital noise.
•
Provide a bypass capacitor of about 22 pF to 33 pF (e.g. Murata GCM1555C1H330JA16) on each
SIM line (
VSIM
,
SIM_CLK
,
SIM_IO
,
SIM_RST
), 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 low capacitance (i.e. less than 1 pF) ESD protection (e.g. Tyco Electronics 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 (Human Body Model according to JESD22-A114),
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 (
SIM_CLK
,
SIM_IO
,
SIM_RST
) to
match the requirements for the SIM interface regarding maximum allowed rise time on the lines.
SARA-N2/N3
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 30: Application circuit for the connection to a single removable SIM card
Reference
Description
Part number - Manufacturer
C1, C2, C3, C4
33 pF capacitor ceramic C0G 0402 5% 50 V
GCM1555C1H330JA16 - Murata
C5
100 nF capacitor ceramic X7R 0402 10% 16 V
GCM155R71C104KA55 - Murata
D1, D2, D3, D4
Very low capacitance ESD protection
PESD0402-140 - Tyco Electronics
J1
SIM card holder
6 positions, without card presence switch
Various manufacturers,
C707 10M006 136 2 - Amphenol
Table 20: Example of components for the connection to a removable SIM card
