Apple Inc.
Inductive Power Transfer System

Abstract:

An inductive power receiving device configured to: supply power received with a power receiving coil to a load in a first mode; determine whether a converter voltage exceeds a threshold voltage; in response to the determining the converter voltage exceeds the threshold voltage after sending a charging mode request, switch to supplying power received with the power receiving coil to the load in a second mode; and in response to determining the converter voltage coil exceeds the threshold voltage before sending the charging mode request is sent, prevent at least a portion of the power received with the power receiving coil from reaching the load. An inductive power transmitting device configured to provide an alternating current voltage to a power transmitting coil and gradually increase the voltage after receiving a charging mode request and stop gradually increasing the voltage once an inductive power receiving device changes modes.