Abstract: Apparatus and methods for dual-mode wireless power transfer are described. Two power transmit coils may be configured to provide magnetic resonant and magnetic inductance wireless power transfer from a same charging area of a wireless power transmitter. The coils and magnetic backing may be arranged to provide similar power transfer performance for the two power transfer methodologies.

Abstract: A foreign object detection method and apparatus for performing same. A wireless power transmitter has a matching network and transmit coil. The method includes, stimulating the transmit coil with electrical signals at a plurality of frequencies, measuring a response of the transmit coil to the electrical signals, determining a quality factor and/or resonant frequency of the transmit coil based upon the measured response, and analyzing the quality factor and/or resonant frequency to determine whether a foreign object is coupled to an electromagnetic field generated by the transmit coil.

Abstract: At least one component for a wireless power transmitter or a wireless power receiver. The at least one component includes a mechanical structure and/or circuitry configured to maintain and/or adjust a coupling coefficient K between the wireless power transmitter and the wireless power receiver, a loaded quality factor Q of the wireless power receiver, or both, such that K times Q is less than a constant.

Abstract: At least one component for a wireless power transmitter or a wireless power receiver. The at least one component includes a mechanical structure and/or circuitry configured to maintain and/or adjust a coupling coefficient K between the wireless power transmitter and the wireless power receiver, a loaded quality factor Q of the wireless power receiver, or both, such that K times Q is less than a constant.

Abstract: A wireless power transmitter apparatus has a gap separating the first magnetic shield and the second magnetic shield, the gap having a magnetic permeability lower than that of the first magnetic shield and the second magnetic shield. A wireless power receiver apparatus has a conductive region within an area defined by a receive coil, the conductive region sized and positioned to inhibit operation of a wireless power transmitter not configured for wireless power transmission to the receive coil.

Abstract: An apparatus and method for performing foreign object detection for a wireless power transmitter. A matching network and transmit coil are energized, and a resonance is excited. The resonance is allowed to decay. A temporal characteristic of the decay is measured. The temporal characteristic is analyzed to determine whether a foreign object is coupled to an electromagnetic field generated by the transmit coil.

Abstract: A wireless power system and methods for operating the same are provided for protection of a wireless power receiver during wireless power transfer. A signal strength limit for the wireless power transmitter is determined based upon a receiver limit, a sensitivity of the wireless power receiver and a scaling factor of the wireless power transmitter.

Abstract: A wireless power transmitter includes a multi-mode drive circuit having a controllable resonant frequency. The multi-mode drive circuit is controlled to have a first resonant frequency to drive wireless power transmission at a first transmit frequency. The multi-mode drive circuit is also controlled to have a second resonant frequency higher than the first resonant frequency to drive wireless power transmission at a second transmit frequency higher than the first transmit frequency.

Abstract: A wireless power transmitter can include a transmitting coil configured to wirelessly transmit power to a receiving coil. The wireless power transmitter can include a shield residing on a given side of a substrate spaced apart from the transmitting coil. The shield can be configured to filter an electric field induced by the transmitting coil.

Abstract: A wireless power transmitter includes a multi-mode drive circuit having a controllable resonant frequency. The multi-mode drive circuit is controlled to have a first resonant frequency to drive wireless power transmission at a first transmit frequency. The multi-mode drive circuit is also controlled to have a second resonant frequency higher than the first resonant frequency to drive wireless power transmission at a second transmit frequency higher than the first transmit frequency.

Abstract: A wireless power assembly including a multi-layer magnetic shield is described. The wireless power assembly includes a wireless power coil and the multi-layer magnetic shield arranged adjacent to the wireless power coil. The magnetic shield includes a first layer comprising a first material and a second layer comprising a second material, wherein the second material has a higher permeability than the first material.

Abstract: A mobile device includes a housing having a conductive region and a wireless power receiver having a receive coil configured to receive wireless power through the conductive region. The thickness of the conductive region is less than ?/10, wherein ? is a skin depth of the conductive region at a primary frequency of an electromagnetic signal that provides the wireless power.

Abstract: Circuits for controlling magnetic-based tracking systems are described. These systems may be used in virtual reality applications, for example to track in real-time the location of one or more body parts. The systems use a beacon emitting mutually orthogonal magnetic fields. On the receiver side, one or more sensors disposed on different parts of a body receive the magnetic fields. The beacon includes switching amplifiers for driving the magnetic field emitters. Being binary, these amplifiers may be controlled by binary signals. The circuits may exhibit a resonant frequency response, and may be operated off-resonance, thus providing for a better control of the magnetic fields amplitude. As a result, however, fluctuations in the envelop of the magnetic fields due to the presence of a beating tone may arise. These fluctuations may be shortened by gradually activating the drivers for the magnetic field emitters.

Abstract: An apparatus and method for performing foreign object detection for a wireless power transmitter. A matching network and transmit coil are energized, and a resonance is excited. The resonance is allowed to decay. A temporal characteristic of the decay is measured. The temporal characteristic is analyzed to determine whether a foreign object is coupled to an electromagnetic field generated by the transmit coil.

Abstract: A wireless power transmitter can include a transmitting coil configured to wirelessly transmit power to a receiving coil. The wireless power transmitter can include a shield residing on a given side of a substrate spaced apart from the transmitting coil. The shield can be configured to filter an electric field induced by the transmitting coil.

Abstract: A wireless power transmitter and/or receiver and methods for operating the same are provided for maintaining an uninterrupted wireless power transfer. A wireless power transmitter and/or receiver adapt at least one wireless power transfer parameter according to at least one operating condition of the wireless power transmitter.

Abstract: Some embodiments relate to a system that includes a first device which is a wireless power transmitter or mobile device and a power adapter external to the first device. The power adapter is configured to receive a control signal and to control a DC output voltage of the power adapter based upon the control signal. The first device is configured to send the control signal to the power adapter.

Abstract: Some embodiments relate to a multi-mode wireless power transmitter. The transmitter includes an inverter configured to produce at its output a first signal having a first frequency or a second signal having a second frequency. The transmitter also includes a first transmit coil coupled to the output of the inverter and configured to wirelessly transmit power at the first frequency. The transmitter also includes a second transmit coil coupled to the output of the inverter and configured to wirelessly transmit power at the second frequency. The transmitter further includes at least one matching network coupled to the first transmit coil, the second transmit coil, and the output of the inverter. The at least one matching network is configured to provide power to the first transmit coil in response to the first signal and inhibit providing power to the second transmit coil in response to the first signal.

Abstract: Methods, apparatus and computer-readable storage media for performing foreign object detection (FOD) in a wireless power transfer system. A plurality of FOD measurements may be performed and processed to perform FOD.

Abstract: At least one component for a wireless power transmitter or a wireless power receiver. The at least one component includes a mechanical structure and/or circuitry configured to maintain and/or adjust a coupling coefficient K between the wireless power transmitter and the wireless power receiver, a loaded quality factor Q of the wireless power receiver, or both, such that K times Q is less than a constant.