User's Manual
LE920 Hardware User Guide
1vv0301026 Rev.8 2015-01-03
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Reserved. Page 34 of 88
4.3.4. Hardware Unconditional Shutdown
To unconditionally Shutdown LE920, the pad SHDN_N 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 SHDN_N 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 SHDN_N must be connected only in open collector
configuration.
NOTE:
The unconditional hardware SHDN_N must always be implemented on the boards. The
software must use it as an emergency exit procedure only, and not as a normal power-off
operation.