Telit Wireless Solutions CE910-DC, Hardware User'S Manual

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The chart below describes the overall sequences for turning ON and OFF the module.
The Unconditional shutdown of the module could be activated using the HW_SHUTDOWN*
line(pad R13).
WARNING:
The hardware unconditional shutdown must NOT be used during normal operation of the device since
it does not detach the device from the network. It shall be used as an emergency exit procedure.
To unconditionally shutdown the CE910, the pad HW_SHUTDOWN* must be tied low for at least
800 milliseconds and then released.
NOTE:
Do not use any pull up resistor on the HW_SHUTDOWN* line nor any totem pole digital output. It is
pulled up internally to VBATT with 57k
Ω
. Using an external pull up resistor may bring latch up
problems on the CE910 power regulator and improper functioning of the module.
The line HW_SHUTDOWN* must be connected only in open collector configuration.
The HW_SHUTDOWN* will generate an unconditional shutdown of the module without an
automatic restart.
The module will shutdown but will NOT perform the detach from the cellular network.