Abstract: A wireless charging system having a power transmitting device may wirelessly transfer power to a power receiving device. The power receiving device may include a voltage regulator that operates independently from the power transmitting device. The voltage regulator may output a rectified voltage and may activate pull-down rectifier switches during zero voltage crossings to boost the rectified voltage. The power receiving device may send control error packets to the power transmitting device to direct the power transmitting device to adjust the transmit power level.

Abstract: A wireless charging system having a power transmitting device may wirelessly transfer power to a power receiving device. The power receiving device may include a voltage regulator that operates independently from the power transmitting device. The voltage regulator may output a rectified voltage and may activate pull-down rectifier switches during zero voltage crossings to boost the rectified voltage. The power receiving device may send control error packets to the power transmitting device to direct the power transmitting device to adjust the transmit power level.

Abstract: Wireless power transfer devices may be configured to negotiate with each other to operate. For example, a wireless power standard may provide for various levels of power delivery, various frequencies for power transfer, various operating voltages, and so forth. There may be instances in which it is desirable to provide wireless power transfer devices (both PTx and PRx) that are capable of enhanced performance when paired with a compatible device. For example, devices can be configured to operate at higher or more granular power levels, different frequencies, and so forth.

Abstract: A wireless power transmitter can receive the results of a characterizing signal transmitted by the wireless power receiver, compute at least two parameters of a model characterizing an in-band communications channel based on the received results of the characterizing signal transmitted by the wireless power receiver, compute a plurality of equalizing filter taps from the at least two parameters, and apply the computed equalizing filter to subsequent signals received by the wireless power transmitter via the in-band communications channel. A first parameter can correspond to a time constant of the channel, and a second parameter can correspond to a damping value of the communications channel. The wireless power transmitter can transmit to a wireless power receiver a request to transmit a characterizing signal through the in-band communication channel, wherein the characterizing signal transmitted by the wireless power receiver is sent in response to the transmitted request.

Abstract: A method of modeling a wireless power transfer system can include constructing a loss-split circuit model of the wireless power transfer system. The loss-split circuit model can include a plurality of resistance values corresponding to power losses in selected components of the power system. The method can further include performing a plurality of finite element analyses to determine the plurality of resistor values. The one or more resistance values can correspond to power losses associated with one or more of: a transmitter coil, a receiver coil, friendly metal associated with a transmitter, friendly metal associated with a receiver, and a foreign object.

Abstract: Wireless power transfer devices may be configured to negotiate with each other to operate. For example, a wireless power standard may provide for various levels of power delivery, various frequencies for power transfer, various operating voltages, and so forth. There may be instances in which it is desirable to provide wireless power transfer devices (both PTx and PRx) that are capable of enhanced performance when paired with a compatible device. For example, devices can be configured to operate at higher or more granular power levels, different frequencies, and so forth.

Abstract: A wireless charging system having a power transmitter may wirelessly transfer power to a power receiver. Shield saturation, such as saturation of a ferrite structure, in the wireless power receiver may occur under some operating conditions. Saturation can lead to disruptive oscillations in power transfer. The power transmitting may include control circuitry for detecting and mitigating saturation.

Abstract: A wireless power transmitter can receive the results of a characterizing signal transmitted by the wireless power receiver, compute at least two parameters of a model characterizing an in-band communications channel based on the received results of the characterizing signal transmitted by the wireless power receiver, compute a plurality of equalizing filter taps from the at least two parameters, and apply the computed equalizing filter to subsequent signals received by the wireless power transmitter via the in-band communications channel. A first parameter can correspond to a time constant of the channel, and a second parameter can correspond to a damping value of the communications channel. The wireless power transmitter can transmit to a wireless power receiver a request to transmit a characterizing signal through the in-band communication channel, wherein the characterizing signal transmitted by the wireless power receiver is sent in response to the transmitted request.

Abstract: A resonant DC-DC converter may include an input for inputting a DC supply voltage, an output for providing a DC voltage to a load, an output rectifier to convert the converter voltage into a DC voltage, a resonant half-bridge inverter comprising two switches in series with a first serial resonant circuit to adjust the output current of the converter, and a second serial resonant circuit to block DC current in the converter and provide current continuity within the converter. The resonance of the first serial resonant circuit is measured after every start of the converter and each measurement defines the switching frequency of the half-bridge inverter. The switches of the half-bridge inverter wherein the driving of the half-bridge inverter includes a key gap during operation thereof. The resonance frequency of the second serial resonant circuit is at least slightly above the switching frequency of the half-bridge inverter.

Abstract: A wireless charging system having a power transmitter may wirelessly transfer power to a power receiver. Shield saturation, such as saturation of a ferrite structure, in the wireless power receiver may occur under some operating conditions. Saturation can lead to disruptive oscillations in power transfer. The power transmitting may include control circuitry for detecting and mitigating saturation.

Abstract: A resonant DC-DC converter may include an input for inputting a DC supply voltage, an output for providing a DC voltage to a load, an output rectifier to convert the converter voltage into a DC voltage, a resonant half-bridge inverter comprising two switches in series with a first serial resonant circuit to adjust the output current of the converter, and a second serial resonant circuit to block DC current in the converter and provide current continuity within the converter. The resonance of the first serial resonant circuit is measured after every start of the converter and each measurement defines the switching frequency of the half-bridge inverter. The switches of the half-bridge inverter wherein the driving of the half-bridge inverter includes a key gap during operation thereof. The resonance frequency of the second serial resonant circuit is at least slightly above the switching frequency of the half-bridge inverter.

Abstract: A wireless power transmitter can receive the results of a characterizing signal transmitted by the wireless power receiver, compute at least two parameters of a model characterizing an in-band communications channel based on the received results of the characterizing signal transmitted by the wireless power receiver, compute a plurality of equalizing filter taps from the at least two parameters, and apply the computed equalizing filter to subsequent signals received by the wireless power transmitter via the in-band communications channel. A first parameter can correspond to a time constant of the channel, and a second parameter can correspond to a damping value of the communications channel. The wireless power transmitter can transmit to a wireless power receiver a request to transmit a characterizing signal through the in-band communication channel, wherein the characterizing signal transmitted by the wireless power receiver is sent in response to the transmitted request.

Abstract: A wireless charging system having a power transmitter may wirelessly transfer power to a power receiver. Shield saturation, such as saturation of a ferrite structure, in the wireless power receiver may occur under some operating conditions. Saturation can lead to disruptive oscillations in power transfer. The power transmitting may include control circuitry for detecting and mitigating saturation.

Abstract: Wireless power transfer devices may be configured to negotiate with each other to operate. For example, a wireless power standard may provide for various levels of power delivery, various frequencies for power transfer, various operating voltages, and so forth. There may be instances in which it is desirable to provide wireless power transfer devices (both PTx and PRx) that are capable of enhanced performance when paired with a compatible device. For example, devices can be configured to operate at higher or more granular power levels, different frequencies, and so forth.

Abstract: Wireless power transfer devices may be configured to negotiate with each other to operate. For example, a wireless power standard may provide for various levels of power delivery, various frequencies for power transfer, various operating voltages, and so forth. There may be instances in which it is desirable to provide wireless power transfer devices (both PTx and PRx) that are capable of enhanced performance when paired with a compatible device. For example, devices can be configured to operate at higher or more granular power levels, different frequencies, and so forth.

Abstract: Techniques are disclosed for measuring an amount of flicker produced by a light source. In one embodiment, a flicker measuring device includes a photo sensor to measure the amount of light produced by the light source, a dedicated processor to receive and process data from the photo sensor, a memory bus coupled to an analog-to-digital converter (ADC) and to a first memory, and a direct memory access (DMA) bus coupled to the ADC and to a second memory. In another embodiment, a flicker measuring system uses a light sensor, an associated circuit and a portable computing device (PCD), such as a smart phone, to measure an amount of flicker produced by a light source by sending an electrical signal from the light source and associated circuit via an audio output to an audio sub-system of the PCD, so that the PCD may calculate the flicker value.

Abstract: Techniques are disclosed for measuring an amount of flicker produced by a light source. In one embodiment, a flicker measuring device includes a photo sensor to measure the amount of light produced by the light source, a dedicated processor to receive and process data from the photo sensor, a memory bus coupled to an analog-to-digital converter (ADC) and to a first memory, and a direct memory access (DMA) bus coupled to the ADC and to a second memory. In another embodiment, a flicker measuring system uses a light sensor, an associated circuit and a portable computing device (PCD), such as a smart phone, to measure an amount of flicker produced by a light source by sending an electrical signal from the light source and associated circuit via an audio output to an audio sub-system of the PCD, so that the PCD may calculate the flicker value.

Abstract: A display, a circuit arrangement for a display and a method of operating a display are disclosed. In an embodiment a display includes a voltage supply and a plurality of pixels. Each pixel includes a given number of light emitters, the light emitters being arranged in parallel electric lines with a light emitter per electric line, wherein the voltage supply is adapted to provide an electric voltage to each of the parallel electric lines. Each electric line comprises a current control element, wherein the current control element of an electric line is configured to control an electric current flowing through the light emitter arranged in the electric line.

Abstract: A display, a circuit arrangement for a display and a method of operating a display are disclosed. In an embodiment a display includes a plurality of pixels, each pixel of the plurality of pixels includes a given number of light emitters, a current control element for each light emitter, the current control element configured to control an electric current through the light emitter and at least one digital circuit element for each light emitter, the at least one digital circuit element configured to provide at least one data value to the current control element and the at least one data value being indicative of the current through the light emitter.

Abstract: A display, a circuit arrangement for a display and a method of operating a circuit arrangement of a display are disclosed. In an embodiment a display includes a plurality of light emitters arranged in a plurality of rows and columns, each row including an electric line and each column including an electric line, a voltage supply for providing a first voltage level to the electric lines of the rows and a second voltage level to the electric lines of the columns and a light emitter arranged in a first row and a first column and interconnecting the electric line of the first row and the electric line of the first column, wherein the electric line of the first column includes a current source, the current source being adapted to be switched on and off and to provide an electric current to drive the light emitter.