An energy harvesting circuit for self-powered sensors

In this work we present a prototype circuit to harvest energy from radio waves or through magnetic coupling based on a stack of full-wave rectifiers with transistors working on sub-threshold region. This circuit will use as an input a field-to-voltage converter capable of outputting a 200mV waveform and is able to self-start without any other energy sources. The circuit presented here is a proof of concept energy-harvesting circuit powering a low frequency ring oscillator which acts as the load. The circuit is designed, simulated and tested in a standard CMOS process, AMS CMOS 0.35 μm.