Switch has to be off when starting because if it's closed, Everycircuit will say "no solution".
This circuit switches on and off a mosfet to make voltage hover around a certain set level.
The voltage controlled voltage source could be replaced by a voltage divider and differential op amp with a gain of 1 irl.
The not gate would be a mosfet driver irl, and the + and - inputs on the op amp could be switched for use with a noninverting mosfet driver.
