Product Info

LTE Standard Module Series
EC25 Series Hardware Design
EC25_Series_Hardware_Design 42 / 126
3.7. Power-on/off Scenarios
3.7.1. Turn on Module Using the PWRKEY
The following table shows the pin definition of PWRKEY.
Table 7: Pin Definition of PWRKEY
When EC25 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. 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.
Turn on pulse
PWRKEY
4.7K
47K
 500 ms
10 nF
Figure 9: Turn on the Module by Using Driving Circuit
The other way to control the PWRKEY is using a button directly. When pressing the key, 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.
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 Qualcomm chipset.