Object Detection Apparatus and Method for Wireless Power Transfer System

A method includes configuring a wireless power transfer system to operate in a sleep mode to reduce a quiescent current of the wireless power transfer system, configuring the wireless power transfer system to operate in a magnetic detection mode, wherein in the magnetic detection mode, an excitation is applied to a resonant tank of the wireless power transfer system, detecting a signal having a resonant attenuation envelope, wherein the signal is generated by the resonant tank, and configuring the wireless power transfer system to operate in an active mode after finding an object is magnetically coupled to the wireless power transfer system.