Users Manual

LTE Standard Module Series
EC25 Hardware Design
EC25_Hardware_Design
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The power-on scenario is illustrated in the following figure.
V
IL
≤0.5V
V
H
=0.8V
VBAT
PWRKEY
≥500ms
RESET_N
STATUS
(OD)
Inactive
Active
UART
NOTE 1
Inactive
Active
USB
≥2.5s
≥12s
≥13s
VDD_EXT
About 100ms
BOOT_CONFIG &
USB_BOOT Pin s
100ms. Afte r this time, the BOOT_CONFIG
pins can b e set to high level by external circuit.
Figure 12: Timing of Turning on Module
1. Please make sure that VBAT is stable before pulling down PWRKEY pin. It is recommended that the
time between powering up VBAT and pulling down PWRKEY pin is no less than 30ms.
2. PWRKEY can be pulled down directly to GND with a recommended 10 resistor if module needs to
be powered on automatically and shutdown is not needed.
3.7.2. Turn off Module
The following procedures can be used to turn off the module normally:
Use the PWRKEY pin.
Use AT+QPOWD command.
NOTES