Product Info

LTE Module Series
EC21 Hardware Design
EC21_Hardware_Design
3-37
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Figure 12: Timing of Turning on Module
Please make sure that VBAT is stable before pulling down PWRKEY pin. The time between them is no
less than 30ms.
3.6.2. Turn off Module
The following procedures can be used to turn off the module:

Normal power down procedure: Turn off the module using the PWRKEY pin.

Normal power down procedure: Turn off the module using AT+QPOWD command.
3.6.2.1. Turn off Module Using the PWRKEY Pin
Driving the PWRKEY pin to a low level voltage for at least 650ms, the module will execute power-down
procedure after the PWRKEY is released. The power-down scenario is illustrated in the following figure.
NOTE