Patent classifications
H03G9/24
Amplifier compensation circuits and methods
Various examples are directed to a frequency-compensated amplifier circuit comprising a first multi-stage amplifier comprising a first amplifier input node, a first amplifier output node, and a first amplifier intermediate node. A first feedback path between the first amplifier input node and the first amplifier output node comprises a feedback resistance. A second feedback path between the first amplifier output node and the first amplifier intermediate node comprises a first capacitor and a portion of the feedback resistance. A first switch circuit may be electrically coupled to the first capacitor and to the feedback resistance. The first switch circuit may have a first state in which the first capacitor is coupled to a first tap point of the feedback resistance and the portion of the feedback resistance has a first value. The first switch circuit may also have a second state in which the first capacitor is coupled to a second tap point of the feedback resistance and the portion of the feedback resistance has a second value different than the first value.
Emphasis circuit
Provided is an emphasis circuit capable of obtaining a desired emphasis amount with which waveform deterioration of an output signal in a high frequency band (high frequency band deterioration) is suppressed without increasing power consumption (current consumption). In the emphasis circuit, a baseband amplifier section and a peaking amplifier section are connected in parallel to each other, and respective drive current setting sections are adjusted to adjust respective drive current values thereof so that the sum of the drive current value of the baseband amplifier section and the drive current value of the peaking amplifier section may be constant.
Emphasis circuit
Provided is an emphasis circuit capable of obtaining a desired emphasis amount with which waveform deterioration of an output signal in a high frequency band (high frequency band deterioration) is suppressed without increasing power consumption (current consumption). In the emphasis circuit, a baseband amplifier section and a peaking amplifier section are connected in parallel to each other, and respective drive current setting sections are adjusted to adjust respective drive current values thereof so that the sum of the drive current value of the baseband amplifier section and the drive current value of the peaking amplifier section may be constant.
AMPLIFIER COMPENSATION CIRCUITS AND METHODS
Various examples are directed to a frequency-compensated amplifier circuit comprising a first multi-stage amplifier comprising a first amplifier input node, a first amplifier output node, and a first amplifier intermediate node. A first feedback path between the first amplifier input node and the first amplifier output node comprises a feedback resistance. A second feedback path between the first amplifier output node and the first amplifier intermediate node comprises a first capacitor and a portion of the feedback resistance. A first switch circuit may be electrically coupled to the first capacitor and to the feedback resistance. The first switch circuit may have a first state in which the first capacitor is coupled to a first tap point of the feedback resistance and the portion of the feedback resistance has a first value. The first switch circuit may also have a second state in which the first capacitor is coupled to a second tap point of the feedback resistance and the portion of the feedback resistance has a second value different than the first value.
Methods and apparatus for adjusting a level of an audio signal
The invention relates to methods and apparatus for adjusting a level of an audio signal. An audio signal is divided into a plurality of frequency bands. Modification parameters are obtained for at least one of the plurality of frequency band. Gain factors are derived for at least one of the plurality of frequency bands, the gain factors determined based on the amplitude scale factors. The gain factors are smoothed. A level of noise from noise compensation factors is determined. The gain factors are applied to at least one of the frequency bands to generate gain adjusted frequency bands. The level of noise is adjusted based on the gain adjusted frequency bands. At least one of the frequency bands is filtered with a filter generated with the filter coefficients. The plurality of frequency bands is synthesized to generate an output audio signal.
Methods and apparatus for adjusting a level of an audio signal
The invention relates to methods and apparatus for adjusting a level of an audio signal. An audio signal is divided into a plurality of frequency bands. Modification parameters are obtained for at least one of the plurality of frequency band. Gain factors are derived for at least one of the plurality of frequency bands, the gain factors determined based on the amplitude scale factors. The gain factors are smoothed. A level of noise from noise compensation factors is determined. The gain factors are applied to at least one of the frequency bands to generate gain adjusted frequency bands. The level of noise is adjusted based on the gain adjusted frequency bands. At least one of the frequency bands is filtered with a filter generated with the filter coefficients. The plurality of frequency bands is synthesized to generate an output audio signal.
Systems and methods for processing an audio signal for replay on an audio device
Systems and methods for processing an audio signal are provided for replay on an audio device. An audio signal is spectrally decomposed into a plurality of subband signals using and pass filters. Each of the subband signals are provided to a respective modulator and subsequently, from the modulator output, provided to a respective first processing path that includes a first dynamic range compressor, DRC. Each subband signal is feedforward compressed by the respective first DRC to obtain a feedforward-compressed subband signal, wherein the first DRC is slowed relative to an instantaneous DRC. Subsequently, each feedforward-compressed subband signal is provided to a second processing path that includes a second DRC, wherein the feedforward-compressed subband signal is compressed by the respective second DRC and outputted to the respective modulator. Modulation of the subband signals is then performed in dependence on the output of the second processing path. Finally, the feedforward-compressed subband signals are recombined.
Methods and Apparatus for Adjusting a Level of an Audio Signal
The invention relates to methods and apparatus for adjusting a level of an audio signal. An audio signal is divided into a plurality of frequency bands. Modification parameters are obtained for at least one of the plurality of frequency band. Gain factors are derived for at least one of the plurality of frequency bands, the gain factors determined based on the amplitude scale factors. The gain factors are smoothed. A level of noise from noise compensation factors is determined. The gain factors are applied to at least one of the frequency bands to generate gain adjusted frequency bands. The level of noise is adjusted based on the gain adjusted frequency bands. At least one of the frequency bands is filtered with a filter generated with the filter coefficients. The plurality of frequency bands is synthesized to generate an output audio signal.
Methods and Apparatus for Adjusting a Level of an Audio Signal
The invention relates to methods and apparatus for adjusting a level of an audio signal. An audio signal is divided into a plurality of frequency bands. Modification parameters are obtained for at least one of the plurality of frequency band. Gain factors are derived for at least one of the plurality of frequency bands, the gain factors determined based on the amplitude scale factors. The gain factors are smoothed. A level of noise from noise compensation factors is determined. The gain factors are applied to at least one of the frequency bands to generate gain adjusted frequency bands. The level of noise is adjusted based on the gain adjusted frequency bands. At least one of the frequency bands is filtered with a filter generated with the filter coefficients. The plurality of frequency bands is synthesized to generate an output audio signal.
Input third order intercept point in low noise amplifier with degeneration tank circuit
A receiver front end having low noise amplifiers (LNAs) with enhanced input third order intercept point is disclosed herein. A cascode having a common source configured input FET and a common gate configured load FET have a degeneration circuit comprising a tank circuit tuned to a harmonic of the operating frequency.