Telit Wireless Solutions HE910-EU V2, Руководство пользователя по оборудованию

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WARNING :
The Hardware Reset must not be used during normal operation of the device since it does not
detach the device from the network. It shall be kept as an emergency exit procedure to be
done in the rare case that the device gets stuck waiting for some network.
To unconditionally shutdown the HE910 V2, the pad HW_SHUTDOWN* must be tied low
for at least 200 milliseconds and then released.
A simple circuit to unconditionally shutdown the module is illustrated below:
NOTE:
Do not use any pull up resistor on the HW_SHUTDOWN* line or any totem pole digital
output. Using a pull up resistor may bring latch up problems on the HE910 V2 power
regulator and result in improper functioning of the module. The line HW_SHUTDOWN*
must be connected only in open collector configuration.
TIP:
The unconditional hardware Shutdown must always be implemented on the boards and the
software must use it only as an emergency exit procedure.