Service Guide

Table Of Contents
LTE Standard Module Series
EG915U_Series_Hardware_Design 36 / 90
The power-up scenario is illustrated in the following figure.
V
IL
0.5 V
VBAT
PWRKEY
2 s
RESET_N
Inactive
ActiveUART
NOTE 1
I nactive ActiveUSB
VDD_EXT
About 1.15 s
4 s
2.23 s
Figure 12: Power-up Timing
.
3.6. Turn Off
The following procedures can be used to turn off the module:
Use the PWRKEY pin.
Use AT+QPOWD.
1. Make sure that the VBAT is stable before pulling down PWRKEY pin. It is recommended that the
time difference between powering up VBAT and pulling down PWRKEY pin is no less than 30 ms.
2. PWRKEY can be pulled down directly to GND with a recommended 1 kΩ resistor if the module
needs to be powered on automatically and shutdown is not needed.
NOTE