Quectel EC21 Series User Manual

LTE Standard Module Series
EC21_Series_Hardware_Design
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Table 8: Pin Definition of PWRKEY
Pin Name Pin No. I/O Description Comment
PWRKEY 21 DI Turn on/off the module
The output voltage is 0.8 V because of the
diode drop in the baseband chipset.
When the module is in power down mode, it can be turned on by driving the PWRKEY pin low for at least
500 ms. It is recommended to use an open drain/collector driver to control the PWRKEY. After STATUS
pin (require external pull-up resistor) outputs a low level, PWRKEY pin can be released.
A simple reference circuit is illustrated in the following figure.
Figure 10: Turn on the Module by Using Driving Circuit
The other way to control the PWRKEY is using a button directly. When pressing the button, electrostatic
strike may generate from finger. Therefore, a TVS component is indispensable to be placed nearby the
button for ESD protection. A reference circuit is shown in the following figure.
Figure 11: Turn on the Module by Using a Button

Quectel EC21 Series Specifications

General

Brand	Quectel
Model	EC21 Series
Category	Control Unit
Language	English