User's Manual

GE866-DUAL Hardware User Guide
1VV0301051 Rev. 2 – 2014-04-07 7
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Reserved. Page 21 of 82
Mod. 0805 2011-07 Rev.2
5.3. Resetting the GE866-QUAD
5.3.1. Hardware Unconditional restart
WARNING:
The hardware unconditional Restart 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 or SIM responses.
To unconditionally reboot the GE866-QUAD, the pad RESET* must
be tied low for at least 200 milliseconds and then released.
The maximum current that can be drained from the ON* pad is
0.15 mA.
NOTE:
Do not use any pull up resistor on the RESET* line nor any
totem pole digital output. Using pull up resistor may bring to
latch up problems on the GE866-QUAD power regulator and
improper functioning of the module. The line RESET* must be
connected only in open collector configuration; the transistor
must be connected as close as possible to the RESET* pin.
TIP:
The unconditional hardware restart must always be implemented
on the boards and the software must use it as an emergency
exit procedure.
A simple circuit to do it is: