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: Techniques for wirelessly charging smart textiles, such as smart garments, are provided. Aspects of the present application provide a smart garment device with an array of integrated coils and rectifiers that enable wireless charging of the device from a drawer or other enclosure that produces a roughly uniform AC magnetic field. The smart garment can draw power from the magnetic field once placed within the enclosure, regardless of how the garment is placed in the enclosure. The method can be applied to garments of any shape, and multiple garments can be charged simultaneously by placing the multiple garments into the same magnetic field.

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: 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: Apparatus and methods for sensing current carried by one or more planar conductors is described. A plurality of sensing coils may be fabricated adjacent to one or more planar, current-carrying conductors. The sensing coils may detect a magnetic field generated by time-varying current flowing through the one or more planar conductors. The sensing coils may be arranged to cancel uniform and linear-gradient magnetic fields.

Abstract: Apparatus and methods for sensing current carried by one or more planar conductors is described. A plurality of sensing coils may be fabricated adjacent to one or more planar, current-carrying conductors. The sensing coils may detect a magnetic field generated by time-varying current flowing through the one or more planar conductors. The sensing coils may be arranged to cancel uniform and linear-gradient magnetic fields.

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: Apparatus and methods for sensing current carried by one or more planar conductors is described. A plurality of sensing coils may be fabricated adjacent to one or more planar, current-carrying conductors. The sensing coils may detect a magnetic field generated by time-varying current flowing through the one or more planar conductors. The sensing coils may be arranged to cancel uniform and linear-gradient magnetic fields.

Abstract: A wireless charging in-band communication system includes a channel encoding for message error correction and detection. A modulation module performs biphase modulation for DC balanced signals and impedance switching to change reflected impedance seen by the source. A synchronization module prepends the message with a synchronization sequence having Golay complementary codes. A receiver module receives the message from the transmitter module. A preamble detection block has a Golay complementary code correlator used for message detection, synchronization, and equalization coefficient estimation and selection. A decoding module that performs biphase demodulation with error correction with a DC offset being estimated as the average value of the signal over the length of the message before channel decoding. The decoding module performs equalization, error correction and detection channel decoding.

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 includes an inverter in which a voltage varies in response to a resonant network and circuitry configured to (A) measure a characteristic indicative of a load seen by the wireless power transmitter, (B) determine a duty cycle of the inverter based upon the characteristic, and (C) switch the inverter with the determined duty cycle.

Abstract: Methods and circuits for controlling a synchronous rectifier. An operating condition of the synchronous rectifier is detected. A voltage level applied to turn on at least one transistor of the synchronous rectifier us modified based upon the detected operating condition, to improve efficiency of the synchronous rectifier.

Abstract: A wireless power transfer apparatus includes a support structure having a top surface and a side surface. The support structure is configured to support a mobile device on the top surface and a wearable device at the side surface. The wireless power transfer apparatus also includes a plurality of transmit coils within the support structure. The plurality of transmit coils are configured to wirelessly transmit power to the mobile device on the top surface and the wearable device at the side surface.

Abstract: A wireless power receiver IC in which the power path can be reconfigured as either a low-dropout regulator (LDO), a switched-mode power supply (SMPS) or a power switch (PSW) is provided. All three modes share the same pass device to reduce die area and share the same output terminal to reduce pin. In an inductive wireless receiver, the power path can be reprogrammed on the fly to LDO or PSW mode or can be reprogrammed on the fly to SMPS or PSW mode. In a resonant or multi-mode wireless receiver, the power path can be reprogrammed on the fly to SMPS or PSW mode. Furthermore, to achieve high power transfer efficiency performance, using N-channel MOSFET as its pass device has better efficiency and smaller die area than P-channel MOSFET pass device.

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: 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: Apparatus and methods for configuring power settings of a wireless power transmitter installed adjacent to a partition are described. A wireless power receiver may detect an amount of power transmitted through the partition from the power transmitter, and identify at least one power setting to the power transmitter that produces an acceptable level of wirelessly transferred power at the wireless power receiver. The power transmitter may store an identified power setting and subsequently operate at the setting identified by the wireless power receiver to provide wireless power through the partition for powering or charging a wirelessly powered device. By configuring a wireless power transmitter at an installation site, various partition thicknesses may be accommodated for through-table, wireless power transfer, for example.

Abstract: Methods and apparatus for providing closed loop current control in a wireless power transmitter. The method comprises adjusting a transmitter coil current generated by the wireless power transmitter based, at least in part, on first feedback reported by at least one wireless power receiver and second feedback based on a measurement of the transmitter coil current.

Abstract: A synchronous rectifier using only n-channel devices in which the low-side switches are effectively cross-coupled using low-side comparators and the high-side switches perform an accurate zero-voltage-switching (ZVS) comparison. The charging path of each bootstrap domain is completed through the low-side switches, which are each always on for every half-cycle independent of loading. This scheme gives rectifier efficiency gain because a) each bootstrap domain receives maximum charging time, and b) the charging occurs through a switch rather than a diode. Both these factors ensure the bootstrap domain is fully charged, thereby reducing conduction losses through the rectifier switches. Furthermore, settings may be adjusted by software to optimize the resistive and capacitive losses of the rectifier. Using data for die temperature and operating frequency, software can create a feedback loop, dynamically adjusting rectifier settings in order to achieve the best possible efficiency.

Abstract: Techniques for wirelessly charging smart textiles, such as smart garments, are provided. Aspects of the present application provide a smart garment device with an array of integrated coils and rectifiers that enable wireless charging of the device from a drawer or other enclosure that produces a roughly uniform AC magnetic field. The smart garment can draw power from the magnetic field once placed within the enclosure, regardless of how the garment is placed in the enclosure. The method can be applied to garments of any shape, and multiple garments can be charged simultaneously by placing the multiple garments into the same magnetic field.