Cutoff power on low voltage

[mitjaj]

I have bought Raspberry Pi and solar powered batteries. Raspberry Pi input voltage should be 4.75 V - 5.25 V by specifications. I have tested what happens when the batteries are nearly empty. Raspberry Pi first restarted few times, then lights flickered and SD card went corrupt. I would need a circuit that would cutoff power when it drops to let say about 4.7 V and would give power back when charged to let say about 5.0 V. I would be grateful for any suggestions.

 

[MikeMl]

I have posted several low/high voltage cutoff switches on these forums using an LM431, such as in this thread. Use the forum "search" feature to find others.

 

[mitjaj]

Thanks.

 

[WTP Pepper]

I have posted several low/high voltage cutoff switches on these forums using an LM431, such as in this thread. Use the forum "search" feature to find others.

You want a circuit with hysteresis otherwise the circuit can still chatter on low battery.

A circuit using hysteresis that goes off at 4.0 volts and wont come on back until the input is >4.8 would do.