Shanghai SIMCom Wireless Solutions Limited SIM7000A ユーザーズマニュアル
Smart Machine Smart Decision
SIM7000 _Hardware Design _V1.00
2017-05-23
Table 9: Power off timing and electronic characteristic
Symbol
Parameter
Time value
Unit
Min.
Typ. Max.
T
off
The active low level time pulse on PWRKEY pin to
power off module
power off module
1.2
-
-
s
T
off(status)
The time from power-off issue to STATUS pin output low
level(indicating power off )*
level(indicating power off )*
1.3
-
-
s
T
off(uart)
The time from power-off issue to UART port off
1.3
-
-
s
T
off(usb)
The time from power-off issue to USB port off
1.3
-
-
s
T
off-on
The buffer time from power-off issue to power-on issue
1
-
-
s
*Note: The STATUS pin can be used to detect whether module is powered on or not. When
module has been powered on and firmware goes ready, STATUS will be high level, or else
STATUS will still low level.
module has been powered on and firmware goes ready, STATUS will be high level, or else
STATUS will still low level.
3.2.3
Reset Function
SIM7000 can be reset by pulling the RESET pin to ground.
Note: This function is only used as an emergency reset. The RESET pin will be ineffectiveness
in the power off mode.
The RESET pin has been pulled up to 1.8V with a 40KΩ resistor internally. So it does not need to
be pulled up externally. It is strongly recommended to put a100nF capacitor and an ESD protection
diode close to the RESET pin. Please refer to the following figure for the recommended reference
circuit.
in the power off mode.
The RESET pin has been pulled up to 1.8V with a 40KΩ resistor internally. So it does not need to
be pulled up externally. It is strongly recommended to put a100nF capacitor and an ESD protection
diode close to the RESET pin. Please refer to the following figure for the recommended reference
circuit.
Figure 12: Reference reset circuit