User's Manual

Smart Machine Smart Decision
SIM7600NA-H_user manual _V1.00 28 2020-1-7
(
Output
)
T
off
( Input
)
T
off(status)
UART Port
UndefinedActive
T
off(uart)
T
on
T
off-on
USB Port
Undefined
Active
T
off(usb)
PWRKEY
STATUS
Figure 11: Power off timing sequence
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
-- 2.5 -- s
T
off(status)
The time from power-off issue to STATUS pin output low
level(indicating power off )*
25 26 - s
T
off(uart)
The time from power-off issue to UART port off 14 15 - s
T
off(usb)
The time from power-off issue to USB port off 27 28 - s
T
off-on
The buffer time from power-off issue to power-on issue 0 - - 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.
3.2.3 Reset Function
MODULE can be reset by pulling the RESET pin down to ground.
Note: This function is only used as an emergency reset, when AT command “AT+CPOF” and
the PWRKEY pin all have lost efficacy.
The RESET pin has been pulled up with a 40KΩ resistor to 1.8V 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.