User Manual
GSM/GPRS Module Series
GC10 Hardware Design
GC10_Hardware_Design Confidential / Released 29 / 76
3.4.2.4. Emergency Shutdown by EMERG_OFF Pin
The module can be shut down by driving the pin EMERG_OFF to a low level voltage over 10ms and then
releasing it. The EMERG_OFF line can be driven by an OC/OD driver or a button. The circuit is illustrated
as the following figures:
Figure 11: An OC Driver for EMERG_OFF
S2
EMERG_OFF
TVS2
Close to S2
Figure 12: Reference Circuit for EMERG_OFF by Button
Be cautious to use the pin EMERG_OFF. It should only be used under emergent situation. For instance, if
the module is unresponsive or abnormal, the pin EMERG_OFF could be used to shut down the system.
Although turning off the module by EMERG_OFF is fully tested and no error is detected, this operation is
still a big risk as it could cause to destroy the code or data area of the flash memory in the module.
Therefore, it is recommended that PWRKEY or AT command should always be the preferential way to
turn off the system.