My arduino is monitoring the 5v output of a regulator (both of which share a common ground) the arduino will read the voltage on a digital pin to know if the regulator is on or not.
but sometimes the arduino is not powered.
but if the arduino is not powered but the regulator is, then the arduino still boots up by drawing power through its IO pin.
so firstly, has anyone else had this problem? and secondly is there any way to isolate the pin but still monitor the supply using minimal extra components?