User's Manual

LE920 Hardware User Guide
1vv0301026 Rev.8 2015-01-03
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Reserved. Page 33 of 88
4.3.3. Hardware Unconditional Restart (RESET)
To unconditionally restart LE920, the pad RESET# must be tied low for period between 500 -
2000 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 cause 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.
NOTE:
Asserting tRESET low for period greater than 2000 milliseconds will cause the module to
shut down.
TIP:
The unconditional hardware Restart must always be implemented on the boards and the
software must use it only as an emergency exit procedure, and not as a normal power-off
operation