Wireless power receiver for mobile devices supporting inductive and resonant operating modes

We demonstrate a compact wireless power receiver for mobile phones that operates either in a resonant mode at 6.78 MHz or an inductive mode in the 110 to 205 kHz range. A coil arrangement and matching network is introduced that is resonant in both frequency bands, allowing the same power conversion circuitry to operate in either mode. The receiver converts up to 5 W of AC power to a regulated 5 V supply with a peak efficiency of 84% in inductive mode and 82% in resonant mode.