no clock; frequency is a function of the input filter RC.
close switch to start.
voltage is sampled from the 0.1Ω current sense resistor, filtered through low pass, amplified and filtered again to make a rough copy of the average voltage across the current sense that ramps up and down
pot picks off a reference voltage and feeds it to the upper comparator with a slight hysteresis feedback to generate a pulse to turn the fet on and increase current through the inductor. the higher the reference voltage, the more current needs to flow through the gate to bring the current sense voltage up.
adjusting the gain of the amplifier changes the response to suit the ohmic resistance of the load.
I'm interested in trying this circuit but I think noise in the filter and amplifier stage will make it inoperable
