Quectel EC21 Series

LTE Standard Module Series
EC21_Series_Hardware_Design
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The power-up scenario is illustrated in the following figure.
Figure 12: Power-up Timing
1. Make sure that VBAT is stable before pulling down PWRKEY pin. It is recommended that the time
between powering up VBAT and pulling down PWRKEY pin is no less than 30 ms.
2. PWRKEY can be pulled down directly to GND with a recommended 10 kΩ resistor if the module
needs to be powered on automatically and shutdown is not needed.
3.7.2. Turn off Module
The following procedures can be used to turn off the module normally:
 Turn off the module using the PWRKEY pin.
NOTE