L
LE920 Hardware User Guide
1vv0301026 Rev.0 - draft4 – 2013-05-
Reproduction forbidden without written authorization from Telit Communications S.p.A. - All Rights Reserved.
Page 30 of 76
4.3.3.
Hardware Unconditional Restart
To unconditionally restart LE920, the pad RESET# must be tied low for at least 200
milliseconds and then released.
A simple circuit to do it is:
NOTE:
Do not use any pull up resistor on the RESET# line or any totem pole digital output. Using
pull up resistor may bring to latch up problems on the LE920 power regulator and improper
functioning of the module. The line RESET# must be connected only in open collector
configuration.
TIP:
The unconditional hardware Restart must always be implemented on the boards and the
software must use it as an emergency exit procedure,
and
not
as a normal power-off operation
RESET#
Unconditional Restart
impulse
GND
