Systems and methods include a digital control module that receives and processes audio data for output through a loudspeaker. An analog block receives the audio data and the power control signal and amplifies the audio data for output. A first processing path includes a buffer to delay the audio data, a first component to combine the buffered audio data and anti-noise. A second processing path includes an absolute value block to receive the audio data and an envelope detector to receive the absolute value data and generate a maximum value for the envelope. An anti-noise path includes an absolute value block configured to determine an anti-noise absolute value which is combined with the absolute value anti-noise data. A power generator receives the output from the envelope detector and updates a power level to approximate a minimum powered needed to process the audio signal.

A device includes a first ramp generator having a first ramp generator output configured to provide a first ramp, a second ramp generator having a second ramp generator output configured to provide a second ramp, and a third ramp generator having a third ramp generator output configured to provide a third ramp. The first ramp is a sawtooth voltage waveform having a first common mode voltage and a first peak-to-peak voltage. The second ramp is a sawtooth voltage waveform having a second common mode voltage and a second peak-to-peak voltage. The third ramp is a sawtooth voltage waveform having a third common mode voltage and a third peak-to-peak voltage. A frequency of the second ramp is approximately equal to a frequency of the third ramp, and the frequency of the third ramp is approximately double a frequency of the first ramp.

Embodiments described herein relate to an envelope tracking system that uses a single-bit digital signal to encode an analog envelope tracking control signal, or envelope tracking signal for brevity. In certain embodiments, the envelope tracking system can estimate or measure the amplitude of the baseband signal. The envelope tracking system can further estimate the amplitude of the envelope of the RF signal. The system can convert the amplitude of the envelope signal to a single-bit digital signal, typically at a higher, oversample rate. The single-bit digital signal can be transmitted in, for example, a low-voltage differential signaling (LVDS) format, from a transceiver to an envelope tracker. An analog-to-digital converter (ADC or A/D) can convert the single-bit digital signal back to an analog envelope signal. Moreover, a driver can increase the power of the A/D output envelope signal to produce an envelope-tracking supply voltage for a power amplifier.

Embodiments described herein relate to an envelope tracking system that uses a single-bit digital signal to encode an analog envelope tracking control signal, or envelope tracking signal for brevity. In certain embodiments, the envelope tracking system can estimate or measure the amplitude of the baseband signal. The envelope tracking system can further estimate the amplitude of the envelope of the RF signal. The system can convert the amplitude of the envelope signal to a single-bit digital signal, typically at a higher, oversample rate. The single-bit digital signal can be transmitted in, for example, a low-voltage differential signaling (LVDS) format, from a transceiver to an envelope tracker. An analog-to-digital converter (ADC or A/D) can convert the single-bit digital signal back to an analog envelope signal. Moreover, a driver can increase the power of the A/D output envelope signal to produce an envelope-tracking supply voltage for a power amplifier.

A power converter configured to generate a high-frequency power signal comprises at least one amplifier stage having first and second amplifier paths each having an amplifier, the first amplifier path outputting a first amplifier path output signal and the second amplifier path outputting a second amplifier path output signal that, has a phase shift relative to the first amplifier path output signal greater than 0° and less than 180°. The first and second amplifier paths are connected to a phase-shifting coupler that is configured to couple the first and second amplifier path output signals to form the high-frequency power signal. At least one amplifier of the first and second amplifier paths comprises a SiC MOSFET.

Methods and devices for communicating or interacting by a pen or a stylus with a digitizer are disclosed. An example method describes determining whether the device is to transmit a first information to the digitizer via the electrode or receive a second information from the digitizer via the electrode. An example device for use with the method includes a transmitter circuit, a receiver circuit, and an electrode. The method further includes isolating the electrode from the transmitter circuit in response to determining that the device is to receive the second information from the digitizer via the electrode.

Methods and devices for communicating or interacting by a pen or a stylus with a digitizer are disclosed. An example method describes determining whether the device is to transmit a first information to the digitizer via the electrode or receive a second information from the digitizer via the electrode. An example device for use with the method includes a transmitter circuit, a receiver circuit, and an electrode. The method further includes isolating the electrode from the transmitter circuit in response to determining that the device is to receive the second information from the digitizer via the electrode.

A semiconductor MOS device having an epitaxial layer with a first conductivity type formed by a drain region and by a drift region. The drift region accommodates a plurality of first columns with a second conductivity type and a plurality of second columns with the first conductivity type, the first and second columns alternating with each other and extending on the drain region. Insulated gate regions are each arranged on top of a respective second column; body regions having the second conductivity type extend above and at a distance from a respective first column, thus improving the output capacitance C.sub.ds of the device, for use in high efficiency RF applications.

Provided is a power supply for envelope tracking, comprising: a first driving unit for finally providing a first current based on a preset and variably-set first high-frequency threshold or threshold interval; a second driving unit for finally providing a second current based on a preset and variably-set second low-frequency threshold or threshold interval; a third driving unit for providing a third current based on a delayed signal; and a superimposing unit for superimposing the first current, the second current, and the third current to provide a supply voltage of a radio-frequency power amplifier. A new power supply for envelope tracking is provided, which is capable of more efficiently providing a supply voltage of the radio frequency power amplifier by superimposing a first current to a third current.

Provided is a power supply for envelope tracking, comprising: a first driving unit for finally providing a first current based on a preset and variably-set first high-frequency threshold or threshold interval; a second driving unit for finally providing a second current based on a preset and variably-set second low-frequency threshold or threshold interval; a third driving unit for providing a third current based on a delayed signal; and a superimposing unit for superimposing the first current, the second current, and the third current to provide a supply voltage of a radio-frequency power amplifier. A new power supply for envelope tracking is provided, which is capable of more efficiently providing a supply voltage of the radio frequency power amplifier by superimposing a first current to a third current.