LTE Standard Module Series
3.5. Turn On
3.5.1. Turn on the Module with PWRKEY
Table 9: Pin Definition of PWRKEY
When the module is in power down mode, it can be turned on to normal mode by driving the PWRKEY pin
to a low level 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.
PWRKEY
4.7K
47K
10 nF
Turn-on pulse
≥
500 ms
Figure 9: Reference Circuit of Turning on the Module 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.
PWRKEY
M odule
S1
Close to S1
TVS
Turn-on pulse
Figure 10: Reference Circuit of Turning on the Module
with button
Pin Name
Pin No.
I/O
Description
Comment
PWRKEY
21
DI
Turn on/off the module
VBAT power domain.
Active low.