Abstract: A method comprises detecting a signal representing a current level at a power switch of a resonant converter with a sense switch coupled to the power switch and formed on a same semiconductor die, wherein the resonant converter comprises a primary side and a secondary side magnetically coupled to the primary side, and adjusting a capacitance of a variable capacitance network of the resonant converter based upon the current level of the power switch.

Abstract: A method includes magnetically coupling a first coil of a wireless power transfer system to a second coil of the wireless power transfer system, wherein the first coil is coupled to a first resonant tank comprising a first variable capacitance network, and the second coil is coupled a second resonant tank comprising a second variable capacitance network, and adjusting a capacitance of at least one of the first variable capacitance network and the second variable capacitance network to regulate an output voltage of the wireless power transfer system.

Abstract: A system includes a switch network coupled to a power source, wherein the switch network comprises a plurality of power switches, a transmitter resonant tank coupled to the plurality of power switches, wherein the transmitter resonant tank comprises a first variable capacitance network, a transmitter coil coupled to the transmitter resonant tank, and a first receiver comprising a first receiver coil configured to be magnetically coupled to the transmitter coil, and a first receiver resonant tank coupled to the first receiver coil, wherein the first receiver resonant tank comprises a second variable capacitance network.

Abstract: A structure comprises a first portion of a winding having a first almost enclosed shape, a second portion of the winding having a second almost enclosed shape and a connection element between the first portion and the second portion, wherein the first portion and the second portion are arranged in a symmetrical manner and the first portion, the second portion and the connection element form a first air core inductor.

Abstract: A method includes coupling a primary side circuit of a resonant power system to a secondary side circuit, wherein the primary side circuit comprises a first resonant tank comprising a first variable capacitance network having a first resonant frequency and the secondary side circuit comprises a second resonant tank having a second resonant frequency and modulating a capacitance of the first variable capacitance network to adjust an operation parameter of the resonant power system.

Abstract: An apparatus comprises a first capacitor and a second capacitor connected in series, a diode and the second capacitor connected in parallel, wherein a cathode of the diode is connected to a common node of the first capacitor and the second capacitor and a plurality of adjustable capacitance networks connected in parallel with the second capacitor.