UMTS/HSDPA Module
UC15 Hardware Design
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Figure 8: Timing of Turning off Module
During power-down procedure, when PWRKEY is pressed, module will send out URC “NORMAL
POWER DOWN” first, then logs off network and saves important data. After logging off, module sends out
“POWERED DOWN” and shut down the internal power supply. The power on VBAT pins is not allowed to
turn off before the URC “POWERED DOWN” is output to avoid data loss. If logging off is not done within
60s, module will shut down internal power supply forcibly.
After that moment, the module enters the power down mode, no other AT commands can be executed.
The power down mode can also be indicated by the STATUS pin.
3.7.2.2. Turn off Module Using AT Command
It is also a safe way to use AT command “AT+QPOWD” to turn off the module, which i
s similar to turning
off the module via PWRKEY Pin
Please refer to
document [1]
for details about the AT command of “AT+QPOWD”.
3.7.2.3. Automatic Shutdown
The module will constantly monitor the voltage applied on the VBAT,
if the voltage
≤
3.5V, the following
URC will be presented:
+QIND: “vbatt”,-1
If the voltage
≥
4.2V, the following URC will be presented:
