Telit Wireless Solutions LE910C1-NS - Unconditional Hardware Shutdown; Figure 8: Circuit for Unconditional Hardware Shutdown; Figure 9 Power down Timing Using HWSHUTDOWNN

LE910C1 Hardware User Guide
1VV0301298 Rev. 1.08 - 2017-11-14
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5.3.4. Unconditional Hardware Shutdown
To unconditionally shut down the LE910C1 module, the HW_SHUTDOWN_N pad must be tied low
for at least 200 milliseconds and then released.
A simple circuit for applying unconditional shutdown is shown below:
Figure 8: Circuit for Unconditional Hardware Shutdown
The system power down timing for using HW_SHUTDOWN_N is shown below
Figure 9 Power down timing using HW_SHUTDOWN_N
NOTE:
Recommended values R2 = 47kΩ, R1 = 10kΩ.
NOTE:
Do not use any pull-up resistor on the HW_SHUTDOWN_N line or any totem pole digital
output. Using a pull-up resistor may cause latch-up problems on the LE910C1 power
regulator and improper functioning of the module. The HW_SHUTDOWN_N line must be
connected only in an open-collector configuration.
NOTE:
The Unconditional Hardware Shutdown must always be implemented on the boards, but the
software must use it only as an emergency exit procedure, and not as a normal power-off
operation.
200
mS Sec < T_Hold
VBATT
SHDN_N
SW_RDY
T_RDY ~0 Sec
V_AUX
PWRMON
T_PWRMON ~0 Sec
OFF StateActive State