switch off circuit when below 0.7 - 1V - UVLO?
The Schottky diode raises the Vin threshold to 1V.. P-FET has Vgs=1V.
Add caps to suit ripple and delay needs.


V Threshold might be 0.8 to 0.9V
Rev A for &lt; few uA bias current.





RdsOn @1V needs to be verified.
Rev A above after spec added for few uA idle current max and 100mA peak load.
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                     - ~ -  original below.









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