Abstract: A wireless power receiver includes one or more tunable capacitors in parallel with an inductor. The wireless power receiver adapted to receive an induced voltage input at the inductor due to a magnetic field generated by a wireless power transmitter. The rectifier has an output with a rectified voltage and a rectified current. A controller has a first input for receiving a signal representative of the rectified voltage and a first output for supplying an adjustment signal to the tunable capacitor. The controller includes a processor coupled to the first input and is configured to operate on the signal representative of rectified voltage to produce a desired capacitance value for capacitor and provide the adjustment signal determined so as to adjust a capacitance value of capacitor to the desired capacitance value.

Abstract: A wireless power receiver includes one or more tunable capacitors in parallel with an inductor. The wireless power receiver adapted to receive an induced voltage input at the inductor due to a magnetic field generated by a wireless power transmitter. The rectifier has an output with a rectified voltage and a rectified current. A controller has a first input for receiving a signal representative of the rectified voltage and a first output for supplying an adjustment signal to the tunable capacitor. The controller includes a processor coupled to the first input and is configured to operate on the signal representative of rectified voltage to produce a desired capacitance value for capacitor and provide the adjustment signal determined so as to adjust a capacitance value of capacitor to the desired capacitance value.

Abstract: A wireless power receiver includes one or more tunable capacitors in parallel with an inductor. The wireless power receiver adapted to receive an induced voltage input at the inductor due to a magnetic field generated by a wireless power transmitter. The rectifier has an output with a rectified voltage and a rectified current. A controller has a first input for receiving a signal representative of the rectified voltage and a first output for supplying an adjustment signal to the tunable capacitor. The controller includes a processor coupled to the first input and is configured to operate on the signal representative of rectified voltage to produce a desired capacitance value for capacitor and provide the adjustment signal determined so as to adjust a capacitance value of capacitor to the desired capacitance value.

Abstract: The disclosure features wireless power transmitters configured to detect a radio frequency identification (RFID) tag, the transmitters including a transmitter resonator, a transmitter impedance matching network coupled to the transmitter resonator, an amplifier coupled to the transmitter impedance matching network, a detection subsystem connected to the transmitter resonator, and a controller coupled to the amplifier and to the detection subsystem and configured so that during operation of the transmitter, the controller is configured to control the transmitter resonator, the amplifier, and the impedance matching network to cycle the transmitter between a power transmission mode and a RFID tag detection mode.

Abstract: A wireless power receiver includes one or more tunable capacitors in parallel with an inductor. The wireless power receiver adapted to receive an induced voltage input at the inductor due to a magnetic field generated by a wireless power transmitter. The rectifier has an output with a rectified voltage and a rectified current. A controller has a first input for receiving a signal representative of the rectified voltage and a first output for supplying an adjustment signal to the tunable capacitor. The controller includes a processor coupled to the first input and is configured to operate on the signal representative of rectified voltage to produce a desired capacitance value for capacitor and provide the adjustment signal determined so as to adjust a capacitance value of capacitor to the desired capacitance value.

Abstract: The disclosure features wireless power transmitters configured to detect a radio frequency identification (RFID) tag, the transmitters including a transmitter resonator, a transmitter impedance matching network coupled to the transmitter resonator, an amplifier coupled to the transmitter impedance matching network, a detection subsystem connected to the transmitter resonator, and a controller coupled to the amplifier and to the detection subsystem and configured so that during operation of the transmitter, the controller is configured to control the transmitter resonator, the amplifier, and the impedance matching network to cycle the transmitter between a power transmission mode and a RFID tag detection mode.

Abstract: The disclosure features mobile electronic devices configured to be wirelessly charged, the devices featuring a receiver resonator configured to capture oscillating magnetic flux, the receiver resonator including: a conductive material layer defining an aperture and a slit extending from the aperture to an outer edge of the conductive material layer, where the conductive material layer forms a back cover of the mobile electronic device, and an inductor having first and second conductor traces, the first trace coupled to a first portion of the conductive material layer adjacent to a first side of the slit and the second trace coupled to a second portion of the conductive material layer adjacent to a second side of the slit.