Product Info

LTE Module Series
EC25 Hardware Design
EC25_Hardware_Design 45 / 112
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 500ms. It is recommended to use an open drain/collector driver to control the
PWRKEY. After STATUS pin (require external pull-up) outputting 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
≥ 500ms
10nF
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 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.
Figure 11: Turn on the Module by Using Button
Pin Name Pin No. I/O Description Comment
PWRKEY 21 DI Turn on/off the module
The output voltage is 0.8V because of
the diode drop in the Qualcomm chipset.