User's Manual

page 12/64
Note d’étude / Technical document : URD1– OTL
5665.3 – 003 / 72238 Edition 01
Document Sagemcom Reproduction et divulgation interdites
Sagemcom document. Reproduction and disclosure prohibited
Figure 5: Protections: EMC and ESD components close to the SIM
 In case of long SIM bus lines over 10cm, it is recommended to also use serial resistors to avoid electrical
overshoots on SIM bus signals. Use 56Ω for the clock line and 10Ω for the reset and data lines.
Figure 6: Protections: Serial resistors for long SIM bus lines.
The schematic here above includes the hardware SIM card presence detector. It can be connected to any GPIO
and managed with an AT command.
 SIM card must not be removed from its holder while it is still powered. First switch the module off properly
with the AT command, then remove the SIM card from its holder.