User's Manual
HiLo3G-850 User Manual
04 March 2011 - Page 8 / 36
Figure 4: SIM Card signals
The HiLo3G-850 module provides SIM signals to the 40 pins. A SIM card holder with 6 pins must be adopted to use the
SIM function.
Decoupling capacitors must be added on VSIM,SIM_DATA,SIM_RST,and SIM_CLK signals as close
as possible to the SIM card connector to avoid EMC issues and pass SIM card approval tests.
Use ESD protection components to protect SIM card and module I/Os against Electro Static Discharges.
The following schematic shows how to protect SIM access of a 6 pins connector. This must be performed every time a SIM
card holder is accessed by the end user customer.
Figure 5: EMC and ESD protection components close to SIM
In cases of long SIM bus lines over 100mm, using serial resistors to avoid electrical overshoots on SIM bus signals is
recommended. Use 56 Ω for the clock line and 10Ω for the reset and data lines.
PIN No.
Name
C1
VCC
C2
RST
C3
CLK
C4
NA
C5
GND
C6
VPP
C7
I/O
C8
N/A
VSIM