Service Guide

LTE Standard Module Series
EG91_Series_Hardware_Design
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Table 7: Pin Definition of PWRKEY
When EG91 series 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. After STATUS pin outputting a high level, PWRKEY pin can be released. A simple
reference circuit is illustrated in the following figure.
Figure 10: Turn on the Module Using Driving Circuit
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.
Figure 11: Turn on the Module Using A Button
Pin Name Pin No. Description Comment
PWRKEY 15 Turn on/off the module
The output voltage is 0.8 V because of
the diode drop in the baseband chipset.