Power Down Module Using At Command; Over-Voltage Or Under-Voltage Automatic Shutdown - Quectel M85 User Manual

Before the completion of the power down procedure, module sends out the result code shown as below:
NORMAL POWER DOWN
After that moment, no further AT commands can be executed. Then the module enters the power down
mode, only the RTC is still active. The power down mode can also be indicated by the STATUS pin, which
is a low level voltage in this mode.
NOTES
1. This unsolicited result codes do not appear when autobauding is active and DTE and DCE are not
correctly synchronized after start-up. The module is recommended to set to a fixed baud rate.
2. As logout network time is related to the local mobile network, it is recommended to delay about 12
seconds before disconnecting the power supply or restarting the module.
3. For more details about the application of STATUS pin, please refer to the Chapter 3.15.

3.4.2.2. Power Down Module Using AT Command

It is also a safe way to turn off the module via AT command AT+QPOWD=1. This command will let the
module to log off from the network and allow the firmware to save important data before completely
disconnecting the power supply.
Before the completion of the power down procedure, module sends out the result code shown as below:
NORMAL POWER DOWN
After that moment, no further AT commands can be executed. And then the module enters the power
down mode, only the RTC is still active.
Please refer to the document [1] for details about the AT command AT+QPOWD.

3.4.2.3. Over-voltage or Under-voltage Automatic Shutdown

The module will constantly monitor the voltage applied on the VBAT, if the voltage is ≤3.5V, the following
URC will be presented:
UNDER_VOLTAGE WARNING
If the voltage is ≥4.5V, the following URC will be presented:
OVER_VOLTAGE WARNING
M85_Hardware_Design Confidential / Released
GSM/GPRS Module Series
M85 Hardware Design
29 / 88