Quectel EC21 Series User Manual

LTE Standard Module Series
EC21_Series_Hardware_Design
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Turn off the module using AT+QPOWD. For details of the command, see document [2].
3.7.2.1. Turn off with PWRKEY
Driving the PWRKEY pin low for at least 650 ms, the module will execute power-off procedure after the
PWRKEY is released. The power-down scenario is illustrated in the following figure.
Figure 13: Power-down Timing
3.7.2.2. Turn off with AT Command
It is also a safe way to use AT+QPOWD to turn off the module, which is similar to turning off the module
via PWRKEY pin.
1. To avoid damaging internal flash, do not switch off the power supply when the module works
normally. Only after the module is shut down by PWRKEY or AT command, then the power supply
can be cut off.
2. When turning off module with the AT command, keep PWRKEY at high level after the execution of
the command. Otherwise, the module will be turned on again after successfully turn-off.
3.8. Reset
The RESET_N pin can be used to reset the module. The module can be reset by driving RESET_N low
NOTE

Quectel EC21 Series Specifications

General

Brand	Quectel
Model	EC21 Series
Category	Control Unit
Language	English