LTE Standard Module Series
EG915U_Series_Hardware_Design 34 / 81
V
IL
≤
0.5 V
VBAT
PWRKEY
≥
2 s
RESET_N
I nactive
Active
UART
Note
1
I nactive
Active
USB
VDD_EXT
About 1.15 s
≥
4 s
≥
2.23 s
Figure 11: Power-up Timing
.
3.6. Turn off
The following procedures can be used to turn off the module:
⚫
Using the PWRKEY pin.
⚫
Using
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 k
Ω resistor if the module
needs to be powered on automatically and shutdown is not needed.
NOTE