User's Manual

Smart Machine Smart Decision
SIM7500A_User Manual_V1.00 2017-06-30
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STATUS
(Output)
T
on
VBAT
PWRKEY
(Input)
T
on(status)
UART Port
Undefined
Active
T
on(uart)
Undefined
Active
USB Port T
on(usb)
Figure 9: Power on timing sequence
Table 8: Power on timing and electronic characteristic
Symbol Parameter Min. Typ. Max. Unit
T
on
The time of active low level impulse of PWRKEY
pin to power on module
100 500 - ms
T
on(status)
The time from power-on issue to STATUS pin
output high level(indicating power up ready )
22 - -
s
T
on(uart)
The time from power-on issue to UART port ready 20 s
T
on(usb)
The time from power-on issue to USB port ready 20 s
V
IH
Input high level voltage on PWRKEY pin 0.6 0.8 1.8 V
V
IL
Input low level voltage on PWRKEY pin -0.3 0 0.5 V
3.2.2 Power off
The following methods can be used to power off Module.
● Method 1: Power off Module by pulling the PWRKEY pin down to ground.
● Method 2: Power off Module by AT command“AT +C POF ”.
● Method 3: Over-voltage or under-voltage automatic power off. The voltage range can be set by
AT command
“AT+ CPM VT ”.
● Method 4: Over-temperature or under-temperature automatic power off.
Note: If the temperature is outside the range of -30~+80℃, some warning will be reported via
AT port. If the temperature is outside the range of -40~+85℃, Module will be powered off
automatically.