User's Manual

SIM7090G User Manual V1.01
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Figure 7: Power on timing sequence
Table 7: 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
1
-
-
s
T
on(Vdd)
The time from power-on issue to VDD_EXT pin
output high level.
64
ms
T
on(status)
The time from power-on issue to STATUS pin output
high level(indicating power up ready )
6.9
-
-
s
T
on(uart)
The time from power-on issue to UART port ready
6.9
-
-
s
T
on(usb)
The time from power-on issue to USB port ready
7.2
-
-
s
V
IH
Input high level voltage on PWRKEY pin
1.0
1.5
1.8
V
V
IL
Input low level voltage on PWRKEY pin
-0.3
0
0.4
V
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.
NOTE