Abstract: An apparatus includes a rectifier coupled to a receiver coil, the receiver coil configured to be magnetically coupled to a transmitter coil of a wireless power transfer system, wherein the rectifier is configured to convert an alternating current voltage into a direct current voltage, a first communication apparatus configured to provide a low speed communication to a transmitter of the wireless power transfer system, and a second communication apparatus configured to provide a high-speed communication to the transmitter of the wireless power transfer system, wherein the high-speed communication provided by the second communication apparatus is enabled through the low speed communication provided by the first communication apparatus.

Abstract: An apparatus includes a substrate of a first conductivity, an extended drain region of a second conductivity formed over the substrate, a body region of the first conductivity formed in the extended drain region, a source region of the second conductivity formed in the body region, a drain region of the second conductivity formed in the extended drain region, a first dielectric layer formed over the body region and the extended drain region, a second dielectric layer formed over the extended drain region, and between the first dielectric layer and the drain region, a first gate formed over the first dielectric layer, and a second gate formed over the second dielectric layer, wherein the second gate is electrically connected to the source region.

Abstract: An apparatus for wireless power reception includes a receiver coil and a rectifier having a first input and a second input, the first input coupled to a first terminal of a receiver coil, the second input coupled to a second terminal of the receiver coil through a resonant capacitor. The apparatus further includes a first capacitor and a first switch network connected in series between the first input and ground and a second capacitor and a second switch network connected in series between the second input and ground, each of the first switch network and the second switch network including at least a plurality of field-effect transistors (FETs) connected in parallel, wherein the first switch network and the second switch network configured to adjust an impedance coupled to the receiver coil, the impedance associated with an Amplitude Shift Keying (ASK) modulation used by the apparatus.

Abstract: A battery charging apparatus includes a first switch, a second switch, a third switch and a fourth switch connected in series between an input voltage bus and ground, wherein a common node of the second switch and the third switch is configured to be coupled to a battery, a flying capacitor connected between a common node of the first switch and the second switch, and a common node of the third switch and the fourth switch, and a controller configured to generate gate drive signals for configuring at least one switch of the first switch and the second switch as a linear regulator during a charging process of the battery.

Abstract: A method includes wirelessly transferring power through a main coil of a wireless power transfer system, wherein the main coil is connected in series with a main resonant capacitor, and the main coil and the main resonant capacitor form a main resonant tank having a first resonant frequency, applying an excitation including a voltage step to an auxiliary resonant tank comprising an auxiliary coil and an auxiliary resonant capacitor, wherein the auxiliary resonant tank has a second resonant frequency different from the first resonant frequency, calculating a quality factor of the wireless power transfer system based on a plurality of parameters derived from a damped sinusoidal waveform obtained from the auxiliary resonant tank, and determining whether a foreign object is magnetically coupled to the wireless power transfer system based on the quality factor.

Abstract: An apparatus includes a first drain/source region and a second drain/source region over a substrate, a first gate adjacent to the first drain/source region, the first gate comprising a plurality of first fingers forming a first comb structure, and a second gate adjacent to the second drain/source region, the second gate comprising a plurality of second fingers forming a second comb structure, wherein the plurality of first fingers and the plurality of second fingers are placed in an alternating manner, and wherein the first drain/source region, the second drain/source region, the first gate and the second gate form two back-to-back connected transistors.

Abstract: A method includes applying a plurality of detection signals to a plurality of receivers, receiving a plurality of echo signals resulted from the plurality of receivers, comparing the plurality of echo signals with a predetermined echo signal distribution pattern, determining the number of the plurality of receivers, and charging the plurality of receivers sequentially using a movable transmitter.

Abstract: A system includes a first coil configured to be magnetically coupled to a second coil, a rectifier coupled to the first coil through a capacitor, a first power stage connected between an output of the rectifier and an output voltage node, and a second power stage coupled between the output voltage node and a battery, wherein the first power stage is configured to charge the battery, and the second power stage is configured to provide isolation between the first power stage and the battery.

Abstract: An apparatus includes a first drain/source region and a second drain/source region over a substrate, and a first gate adjacent to the first drain/source region and a second gate adjacent to the second drain/source region, wherein the first gate and the second gate are separated from each other, wherein the first drain/source region, the second drain/source region, the first gate and the second gate form two back-to-back connected transistors.

Abstract: An apparatus includes a controller configured to control switches of a rectifier circuit, wherein the rectifier circuit is coupled to two terminals of a receiver coil configured to be magnetically coupled to a transmitter coil of a wireless power transfer system, and wherein in response to a high system gain of the wireless power transfer system, the controller configures the rectifier circuit as a half-bridge rectifier, and in response to a low system gain of the wireless power transfer system, the controller configures the rectifier circuit as a full-bridge rectifier.

Abstract: An apparatus includes a receiver coil configured to be magnetically coupled to a transmitter coil, and a rectifier circuit coupled to two terminals of the receiver coil, wherein in response to a high system gain of the apparatus, the rectifier circuit is configured as a half-bridge rectifier, and in response to a low system gain of the apparatus, the rectifier circuit is configured as a full-bridge rectifier.

Abstract: The disclosure includes a foreign object detection circuit and a foreign object detection method. The method comprises: step a) establishing a communication link between a transmitter and a receiver in a wireless power transmission system; step b) performing, by the transmitter and the receiver, wireless power transmission based on the magnetic coupling; and step c) measuring a quality factor of a receiver terminal, and determining whether a foreign object exists in the wireless power transmission system or not based on the quality factor. In accordance with a foreign object detection circuit and a foreign object detection method provided by the present invention, the problem that the foreign object cannot be detected effectively in the prior art is solved.

Abstract: A method includes configuring a wireless power transfer system to operate in a sleep mode to reduce a quiescent current of the wireless power transfer system, configuring the wireless power transfer system to operate in a magnetic detection mode, wherein in the magnetic detection mode, an excitation is applied to a resonant tank of the wireless power transfer system, detecting a signal having a resonant attenuation envelope, wherein the signal is generated by the resonant tank, and configuring the wireless power transfer system to operate in an active mode after finding an object is magnetically coupled to the wireless power transfer system.

Abstract: An apparatus includes a controller configured to control switches of a receiver, the receiver comprising a first receiver coil configured to be magnetically coupled to a transmitter coil of a wireless power transfer system, a rectifier circuit coupled to two terminals of the first receiver coil, a second receiver coil and a first auxiliary switch, wherein the second receiver coil is connected in series with the first auxiliary switch, and the second receiver coil is configured to be magnetically coupled to the transmitter coil, and wherein in response to a low power mode of the apparatus, the controller is configured to turn on the first auxiliary switch such that the first receiver coil and the second receiver coil are connected in series to boost a gain of the wireless power transfer system.

Abstract: A method includes providing a current flowing through a first flying capacitor of a switched-capacitor power converter, measuring a first voltage at one terminal of the first flying capacitor at a first voltage measurement time instant, measuring a second voltage at the one terminal of the first flying capacitor at a second voltage measurement time instant, and calculating a capacitance value of the first flying capacitor based on the first voltage, the second voltage, the first voltage measurement time instant and the second voltage measurement time instant.

Abstract: An apparatus includes a first receiver coil configured to be magnetically coupled to a transmitter coil, a rectifier circuit coupled to two terminals of the first receiver coil, a second receiver coil and a first auxiliary switch connected in series, wherein the second receiver coil is configured to be magnetically coupled to the transmitter coil, and in response to a low power mode of the apparatus, the first auxiliary switch is configured to be turned on such that the first receiver coil and the second receiver coil are connected in series to boost a gain of the apparatus.

Abstract: An apparatus includes a rectifier coupled to a coil of a wireless power transfer system, the rectifier comprising a first leg and a second leg, wherein the first leg comprises a first switch and a second switch connected in series between a first voltage bus and a second voltage bus, and the second leg comprise a third switch and a fourth switch connected in series between the first voltage bus and the second voltage bus, and wherein a gate drive signal of the first switch is derived from a signal in phase with a voltage on a first terminal of the coil, and a gate drive signal of the third switch is derived from a signal in phase with a voltage on a second terminal of the coil.

Abstract: A power converter includes a plurality of switches coupled between an input bus and an output bus, a full bridge coupled between the output bus and ground, and a plurality of capacitors coupled between the plurality of switches and the full bridge, wherein one capacitor of the plurality of capacitors is connected to a midpoint of one leg of the full bridge through a switch.

Abstract: A power converter includes a plurality of switches coupled between an input bus and an output bus, a full bridge coupled between the output bus and ground, and a plurality of capacitors coupled between the plurality of switches and the full bridge, wherein one capacitor of the plurality of capacitors is connected to a midpoint of one leg of the full bridge through a switch.

Abstract: A method includes detecting a signal on a switching node connected to a power switch, detecting a gate drive voltage of the power switch, during a gate drive process of the power switch, reducing a gate drive current based on a first comparison result obtained from comparing the signal with a first threshold, and during the gate drive process of the power switch, increasing the gate drive current based on a second comparison result obtained from comparing the gate drive voltage with a second threshold.