Quectel QuecOpen AG521R-NA Hardware Design page 44

PWRKEY 7
When the module is in power-off mode, it can be turned on by driving PWRKEY low for at least 500 ms. It is
recommended to use an open drain/collector driver to control the PWRKEY. A simple reference circuit is illustrated
in the following figure.
Turn on pulse
Another way to control the PWRKEY is using a button directly. When pressing the key, electrostatic strike may
generate from the 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.
The power on scenario is illustrated in the following figure.
AG521R-NA_QuecOpen_Hardware_Design
Turn on/off the module
500 ms
4.7K
Figure 10: Turn on the Module Using Driving Circuit
S1
Figure 11: Turn on the Module Using Keystroke
AG521R-NA QuecOpen Hardware Design
V max = 1.89 V
IH
V min = 1.17 V
IH
V max = 0.63 V
IL
47K
PWRKEY
TVS
Close to S1
Automotive Module Series
1.8 V power domain.
Pulled-up internally.
Active low.
PWRKEY
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