Active rectifier and method for energy harvesting power management circuit

摘要

An active rectifier (12) couples a first input voltage (Vin1) to a first electrode of a first transistor (M3) having a second electrode coupled to an output (4) conducting an output voltage (Vout), and couples a second input voltage (Vin2) to a first electrode of a second transistor (M4) having a second electrode coupled to the output conductor. A first amplifier (A1) controls a voltage (V16) of a gate of the first transistor to maintain an input offset of the first amplifier between the first input voltage and the output voltage while the first input voltage exceeds the output voltage, and a second amplifier (A2) controls a voltage (V15) on a gate of the second transistor to maintain an input offset between the second input voltage and the output voltage while the first input voltage exceeds the output voltage. The input offsets prevent backflow of current from the output to either of the first electrodes when the first or second input is nearly equal to the output voltage.