US Patent 10063138 Bridgeless power factor correction circuits

A power factor correction circuit comprises a pair of III-N based switches coupled to a first reference ground, and an inductive component connected in series with a current sensing resistor. A first side of the current sensing resistor is coupled to a second reference ground which is electrically isolated from the first reference ground, and a second side of the current sensing resistor is coupled to a control circuit. The control circuit is also coupled to the second reference ground and is configured to measure current flowing through the inductive component during operation of the power factor correction circuit.