Sunsea AIoT SIMCom SIM7075G User Manual page 25

The time from power-on issue to VDD_EXT pin
Ton(Vdd)
output high level.
The time from power-on issue to STATUS pin output
Ton(status)
high level(indicating power up ready )
Ton(uart) The time from power-on issue to UART port ready
Ton(usb) The time from power-on issue to USB port ready
VIH Input high level voltage on PWRKEY pin
VIL Input low level voltage on PWRKEY pin
NOTE
1. PWRKEY cannot be shorted all the way to GND.
2. It is recommended to ensure that the VBAT voltage rises and stabilizes before pulling down the
PWRKEY pin to start up.
3. Before turning on the module, be sure to pay attention to the maximum conditions (such as voltage
and temperature range) allowed by the module, otherwise exceeding the absolute maximum value
of the module may cause permanent damage to the module.
4. The ESD protection diode junction capacitance on the PWR cannot exceed 10pF, otherwise the
module may be turned on automatically.
3.2.2 Power off
The following methods can be used to power offSIM7075G.
Method 1: Power off SIM7075G by pulling the PWRKEY pin to ground.
●
Method 2: Power off SIM7075G by AT command "AT+CPOWD=1".
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Method 3: over-voltage or under-voltage automatic power off. The function can be enabled by AT
●
command "AT+CBATCHK=1". Default is disabled.
NOTE
For details about "AT+CPOWD" and "AT+CBATCHK", please refer to Document [1].
It is not recommended to turn off the module by disconnecting VBAT power. Otherwise, there is a risk of
damage to the module file system.
These procedures will make modules disconnect from the network and allow the software to enter a safe
state, and save data before module be powered off completely.
The power off scenario by pulling down the PWRKEY pin is illustrated in the figure 10.
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