A signal processing circuit includes an input inverter and an output inverter. Each inverter has a signal input for receiving an input rectangular signal, a signal output for providing an inverted output rectangular signal, and a pair of voltage outputs for developing a rectified dc output voltage. A first circuit input terminal is connected to the output of the input inverter and the input of the output inverter. A second circuit input terminal is connected to the input of the input inverter and the output of the output inverter, wherein the signal input terminals receive an input signal having a data component. A pair of supply voltage output terminals is connected to the voltage output terminals of the inverters for providing a rectified dc supply voltage output. A first circuit output terminal is connected to one of the supply voltage output terminals, and a second circuit output terminal connected to the second circuit input terminal, wherein the circuit output terminals provide an output signal including the data component.