Integration Manual

Table Of Contents
SARA-R5 series - System integration manual
UBX-19041356 - R03 Design-in Page 72 of 123
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Connect one pin of the normally-open mechanical switch integrated in the SIM connector (as the
SW2 pin in Figure 48) to the GPIO5 input pin, providing a weak pull-down resistor (e.g. 470 k, as
R2 in Figure 48).
Connect the other pin of the normally-open mechanical switch integrated in the SIM connector
(SW1 pin in Figure 48) to V_INT 1.8 V supply output by means of a strong pull-up resistor (e.g. 1 k,
as R1 in Figure 48)
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 47 pF (e.g. Murata GCM1555C1H470JA16) 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 10 pF) ESD protection (e.g. Tyco Electronics
PESD0402-140) on each externally accessible SIM line, close to each related pad of the SIM
connector. The ESD sensitivity rating of SIM interface pins is 1 kV (HBM 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.
Limit capacitance and series resistance on each SIM signal to match the requirements for the SIM
interface regarding maximum allowed rise time on the lines.
SARA-R5 series
41
VSIM
39
SIM_IO
38
SIM_CLK
40
SIM_RST
4
V_INT
42
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
Figure 48: 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
GCM1555C1H470JA16 - Murata
C5
100 nF capacitor ceramic X7R 0402 10% 16 V
GCM155R71C104KA55 - Murata
D1 D6
Very low capacitance ESD protection
PESD0402-140 - Tyco Electronics
R1
1 k resistor 0402 5% 0.1 W
Generic manufacturer
R2
470 k resistor 0402 5% 0.1 W
Generic manufacturer
J1
SIM card holder, 6 + 2 positions, with card presence switch
Generic manufacturer,
as CCM03-3013LFT R102 - C&K Components
Table 28: Example of components for the connection to a single removable SIM card, with SIM detection implemented