The feedback circuit transforms any incoming signal to a perfect square wave, if we apply a pulsed signal to a resistor (the cell) throught an inductor, the signal across th plates will look as a triangle wave (if the inductor do not saturate), and at the output of the opamp it will be a perfect square wave.
This is a very useful circuit, I am building a speeduino board, and guess what I'm using for VR conditioner (crankshaft sensor) ? Meyer feedback circuit. It gives me a very nice 5v square wave.
Cheers
