Emergency Shutdown - Quectel UG96 Manual

HSPA/UMTS/GSM/GPRS Module Series
UG96&UG95&M95 R2.0 Compatible Design
The power-off scenario is illustrated as the following figure.
VBA T
0.7s<pull-down<1s
Log out from network in 2s~12s
PWRKEY
(INP UT)
STATUS
(OUTPUT)
EMERG_OFF
(INP UT)
Figure 8: M95 R2.0's Power-off Scenario
NOTE
Network logout time is related to local network signal strength.

4.3.3. Emergency Shutdown

UG96/UG95 can be shut down by PWRDWN_N pin and M95 R2.0 can be shut down by EMERG_OFF
pin. The two pins should only be used under emergency situations, such as when the module crashes or
works abnormally. Although turning off the module by PWRDWN_N or EMERG_OFF is fully tested and
nothing wrong detected, this operation is still a big risk as it could cause destroying of 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 module.
The following circuit is a reference design for UG96/UG95 and M95 R2.0's emergency shutdown.
Module
PWRDWN_N (UG96/UG95)
EMERG_OF F (M95 R2.0)
4.7K
pulse
47K
Figure 9: Driving Circuit of Emergency Shutdown
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