I have an application where Vin comes from a battery pack (3V - 7V) but on occasion and under heavy load, Vin drops to just above 2V for ~ 1 seconds before recovering.
There is a 3.3V LDO that provides power to the microcontroller. The LDO uses a pass transistor to regulate the voltage, and due to the body diode, current can travel from output to input when Vout > Vin + 0.2
To prevent the microcontroller from resetting, my intent was to add a capacitor large enough to keep the microcontroller alive until the battery voltage recovered.
However the body diode would conduct at a certain point, and the energy that would have gone to the microcontroller, would now be going to the LDO as well. I am not sure how much energy would be lost here.
This both an energy and cost sensitive project.
What can possible by done other than throwing a diode at the output of the LDO (Would like to minimize that energy loss) ?