Abstract: A system for inductive power transfer includes a charger. The charger is an inductive charger. The system also includes a first mobile device that includes a receiver to inductively receive power for the first mobile device. A charger for inductive charging includes a printed circuit board having a charger coil, a substantially planar magnetic layer, a charger drive circuit, and means for positioning a receiver in a power transfer position. A mobile device that receives power inductively includes a receiver to inductively receive power for the mobile device. A method for inductive power transfer to a mobile device, which includes a receiver, includes positioning the receiver in a power transfer position to inductively receive power from an inductive charger. The method further includes inductively transferring power from the charger to the receiver of the first mobile device.

Abstract: The invention enables efficient wireless power transfer, and charging of devices and batteries, in a manner that allows freedom of placement of devices or batteries in one or multiple dimensions. Provided is a base unit for wireless power transfer or charging through a time varying magnetic field. The unit typically includes a magnetic material or layer that guides magnetic flux generated by a charger coil as to create a preferential path for returning magnetic flux from a receiver coil in one or multiple dimensions. The receiver may include a magnetic core having a magnetic permeability exceeding 1 with copper Litz wire around a ferrite core. With power receivers proximate to the base unit, the base unit coil may inductively generate a current in receiver coils or receivers associated with the power receivers. Uni-directionally or bi-directionally wireless communication protocols include NFC, Bluetooth, WiFi, and etc. control and optimize power transfer therebetween.

Abstract: An inductive charger where the charging surface or coil is separated from the drive or control electronics is described.

Abstract: A power source, charging system, and inductive receiver for mobile devices. A pad or similar base unit comprises a primary, which creates a magnetic field by applying an alternating current to a winding, coil, or any type of current carrying wire. A receiver comprises a means for receiving the energy from the alternating magnetic field and transferring it to a mobile or other device. The receiver can also comprise electronic components or logic to set the voltage and current to the appropriate levels required by the mobile device, or to communicate information or data to and from the pad. The system may also incorporate efficiency measures that improve the efficiency of power transfer between the charger and receiver.

Abstract: An inductive charging system for inductive charging of electronic devices is disclosed. In accordance with an embodiment, the system includes a substantially planar inductive charging coil parallel to the surface of the inductive charger or the electronic device. The system further includes a metallic layer positioned proximate to and substantially parallel to the inductive coil to cover a surface of the inductive coil. The metallic layer comprises multiple substantially concentric rings or polygons, with each of the concentric rings or polygons having multiple sections separated by gaps such that each concentric ring or polygon is discontinuous. Adjacent sections of each concentric ring or polygon are electrically isolated from one another to avoid eddy current generation and heating of the metallic layer during inductive power transfer.

Abstract: An electronic device having an inductive power transfer system to transfer power to a portable device is disclosed. The electronic device includes a first inductive coil for power transfer using an alternating magnetic field. The electronic device further includes a permanent magnet structure for creating a separable magnetic attachment between the electronic device and the portable device having a second inductive coil for inductive power transfer. The permanent magnet structure is positioned around an outer perimeter of the first inductive coil to align the first inductive coil with the second inductive coil in the portable device for inductive power transfer. The permanent magnet structure includes one or more discontinuous arc-shaped permanent magnets assembled to form a full or partial ring shape that includes a gap to impede eddy current generation in the permanent magnet structure by the alternating magnetic field during inductive power transfer.

Abstract: A system for inductive power transfer includes a charger. The charger is an inductive charger. The system also includes a first mobile device that includes a receiver to inductively receive power for the first mobile device. A charger for inductive charging includes a printed circuit board having a charger coil, a substantially planar magnetic layer, a charger drive circuit, and means for positioning a receiver in a power transfer position. A mobile device that receives power inductively includes a receiver to inductively receive power for the mobile device. A method for inductive power transfer to a mobile device, which includes a receiver, includes positioning the receiver in a power transfer position to inductively receive power from an inductive charger. The method further includes inductively transferring power from the charger to the receiver of the first mobile device.

Abstract: A system and method for distributed charging of mobile devices. In accordance with an embodiment, the system comprises a secondary coil or receiver associated with a mobile device. When the mobile device is placed in proximity to a base unit having one or more primary coils, each primary coil having a generally planar shape so that when a current is passed through the primary coil a magnetic field is generated in a direction substantially perpendicular to the plane of the primary coil, the perpendicular magnetic field is used to inductively generate a current in the secondary coil or receiver associated with the mobile device, to charge or power the mobile device. In accordance with various embodiments the system can incorporate efficiency measures that improve the efficiency of power transfer between the charger and receiver.

Abstract: A system for providing power inductively to a portable device is disclosed. The system a primary coil, a drive circuit, a sense circuit, and a communication and control circuit. The communication and control circuit is configured to perform operations, including detection of communication and drive circuit operations. A portable device that includes a receiver unit coupled to a battery and configured to receive inductive power from an inductive charging system including a base unit with a primary coil and associated circuit is also disclosed. The receiver unit includes a receiver coil, a ferrite layer, and a receiver circuit. The receiver circuit includes a receiver communication and control circuit to modulate current in the receiver coil to communicate with a base unit while the receiver circuit is being powered by the inductive charging system.

Abstract: An inductive charger where the charging surface or coil is separated from the drive or control electronics is described.

Abstract: A system for providing power inductively to a portable device is disclosed. The system a primary coil, a drive circuit, a sense circuit, and a communication and control circuit. The communication and control circuit is configured to perform operations, including detection of communication and drive circuit operations. A portable device that includes a receiver unit coupled to a battery and configured to receive inductive power from an inductive charging system including a base unit with a primary coil and associated circuit is also disclosed. The receiver unit includes a receiver coil, a ferrite layer, and a receiver circuit. The receiver circuit includes a receiver communication and control circuit to modulate current in the receiver coil to communicate with a base unit while the receiver circuit is being powered by the inductive charging system.

Abstract: A system and method for distributed charging of mobile devices. In accordance with an embodiment, the system comprises a secondary coil or receiver associated with a mobile device. When the mobile device is placed in proximity to a base unit having one or more primary coils, each primary coil having a generally planar shape so that when a current is passed through the primary coil a magnetic field is generated in a direction substantially perpendicular to the plane of the primary coil, the perpendicular magnetic field is used to inductively generate a current in the secondary coil or receiver associated with the mobile device, to charge or power the mobile device. In accordance with various embodiments the system can incorporate efficiency measures that improve the efficiency of power transfer between the charger and receiver.

Abstract: A power source, charging system, and inductive receiver for mobile devices. A pad or similar base unit comprises a primary, which creates a magnetic field by applying an alternating current to a winding, coil, or any type of current carrying wire. A receiver comprises a means for receiving the energy from the alternating magnetic field and transferring it to a mobile or other device. The receiver can also comprise electronic components or logic to set the voltage and current to the appropriate levels required by the mobile device, or to communicate information or data to and from the pad. The system may also incorporate efficiency measures that improve the efficiency of power transfer between the charger and receiver.

Abstract: A system for power inductively to a portable device is disclosed. In accordance with an embodiment the system includes a first primary coil that provides power inductively at a first power level and a second primary coil that provides power inductively at a second power level different from the first power level. The first primary coil and the second coil area are different in size and overlap one another partially. The system further includes a communication and control circuit that receives current modulated information in the primary coil that provides power. The received information includes information corresponding to a voltage or current induced by the primary coil that provides power, a unique identification code, and a manufacturer code. The system selects which primary coil to use to charge the portable device based on the received information.

Abstract: Systems for inductive charging and electronic devices for receiving inductive charge are disclosed. They include a coil, a plurality of resonant capacitors, and one or more capacitor switches that electrically couple a selection of the resonant capacitors to the coil. In a first mode of operation, the capacitor switches couple a first selection of the resonant capacitors to the coil to form a resonant circuit having a first resonant frequency to operate at a first power level. In a second mode of operation, the capacitor switches couple a second selection of the resonant capacitors to the coil to form a resonant circuit having a second resonant frequency to operate at a second power level.

Abstract: A system for power inductively to a portable device is disclosed. In accordance with an embodiment the system includes a first primary coil that provides power inductively at a first power level and a second primary coil that provides power inductively at a second power level different from the first power level. The first primary coil and the second coil area are different in size and overlap one another partially. The system further includes a communication and control circuit that receives current modulated information in the primary coil that provides power. The received information includes information corresponding to a voltage or current induced by the primary coil that provides power, a unique identification code, and a manufacturer code. The system selects which primary coil to use to charge the portable device based on the received information.

Abstract: A system for inductive charging of electronic devices is disclosed. An inductive charger includes an enclosure with a charging surface, an inductive charging coil, and a metallic shield layer. The coil includes a spiral-shaped conductor that transmits power through the charging surface with an alternating magnetic field when an electronic device is positioned in proximity to the charging surface. The shield layer is positioned between the conductor and the charging surface such that the shield layer covers the conductor, and it provides a frequency-dependent response in which transmission of electromagnetic power through the shield layer is allowed in the frequency range while transmission of electromagnetic interference noise through the first shield layer is attenuated at frequencies higher than the frequency range.

Abstract: An electronic device having an inductive power transfer system is disclosed. The electronic device includes an inductive coil for inductive power transfer using an alternating magnetic field and a permanent magnet for creating a separable magnetic attachment between the electronic device and a second device having an inductive coil. The permanent magnet is positioned substantially at the geometric center of the inductive coil to align the inductive coil with the inductive coil in the second device. The permanent magnet has substantially flat first and second surfaces substantially parallel to the inductive coil, and the permanent magnet is manufactured to have an electrical resistivity to impede eddy current generation in the permanent magnet and heating of the permanent magnet by the alternating magnetic field during inductive power transfer.

Abstract: Provided is a base for wirelessly charging and/or wirelessly powering in which multiple inductive charging protocols are used, with one of the protocols using uni-directional messaging and another of the protocols using bi-directional messaging. Different inductive charging protocols using different frequency ranges are also described.

Abstract: Systems include a coil, a drive circuit, a sense circuit, and a communication and control circuit for providing power inductively to a portable device comprising a battery and an inductive receiver unit including a receiver coil and a receiver circuit. A portable device includes a battery and a receiver unit capable of receiving inductive power from a compatible inductive charging system including a base unit with a primary coil and associated circuit.