/diy/ - Do It Yourself

>>1216859
That middle 100MΩ isn't needed at all, btw. Here's the comparator design with the resistors on either side of the comparator's "-" input being the potentiometer, the 1kΩ resistor can be a normal resistor of whatever size is convenient. When it comes to comparators it's best to keep the threshold voltage within the middle 80%, because they don't respond well to the rails. The FET on the end can also be any transistor or relay in this model, provided the comparator can source enough current.