Patent ID: 9577438
Date: 2017-02-21
CPC Classifications: H02J,H02M,H04B,Y02B

Claim:
1. A transmitter for wireless power transfer, comprising: a TX coil; a capacitor coupled across the TX coil; at least one inductor coupled between a power source and the TX coil; a pair of switching FETs including a first switching FET coupled between a first side of the capacitor and ground and a second switching FET coupled between a second side, opposite the first side, of the capacitor and ground, the gates of the first switching FET and the second switching FET being driven to provide an oscillating current through the TX coil, wherein the gate of the first switching FET is switched from off to on and the gate of the second switching FET is switched from on to off when a first voltage across the second switching FET decreases to zero volts; and a resonant frequency shifting circuit coupled between drains of the first switching FET and the second switching FET, the resonant frequency shifting circuit being driven by a modulator.