Abstract: An arrangement for pulse-width modulating an analog or digital input signal is provided. The non-linear distortion generated in the pulse-width modulator is precompensated by applying a signal with reversed error to the pulse-width modulator. The signal with reversed error is generated by a further pulse-width modulator that receives the input signal and whose output signal is subtracted from twice the input signal. The arrangement may e.g. be used to drive class D audio amplifiers.

Abstract: An arrangement for pulse-width modulating an analog or digital input signal is provided. The non-linear distortion generated in the pulse-width modulator is precompensated by applying a signal with reversed error to the pulse-width modulator. The signal with reversed error is generated by a further pulse-width modulator that receives the input signal and whose output signal is subtracted from twice the input signal. The arrangement may e.g. be used to drive class D audio amplifiers.

Abstract: Sigma-delta modulation is provided, comprising feeding an input signal to a first SDM, subtracting the output of the first SDM from the input signal, filtering the output of the subtracting to obtain a filtered signal, delaying the input signal, adding the filtered signal to the delayed signal, feeding the output of the adder to a second SDM and providing the output of the second SDM. The first SDM in combination with the subtracting and filtering delivers a correction signal which, by adding it to the input signal, reduces the distortion in the second SDM, which second SDM performs in fact the sigma-delta modulation of the device.

Abstract: Estimating a compression gain obtainable in compressing a given audio signal, comprising extracting a signal power in a selected frequency band of the given audio signal, and obtaining an estimation of the compression gain by correlation with the extracted signal power.

Abstract: Estimating a compression gain obtainable in compressing a given audio signal, comprising extracting a signal power in a selected frequency band of the given audio signal, and obtaining an estimation of the compression gain by correlation with the extracted signal power.

Abstract: A digital to analog converter for converting a multi bit digital input signal into an analog output signal. The converter includes a plurality of substantially equal conversion elements on a semiconductor chip and which are selected in accordance with a dynamic element matching algorithm. The dynamic element matching algorithm is adapted to the position of the conversion elements on the semiconductor chip so as to improve the shaping of the noise caused by the systematic, i.e. position dependent, errors of the conversion elements.

Abstract: Processing an audio signal is provided, which processing comprises conversion of the audio signal into a digital signal by a noise-shaping modulation, compressive encoding of the digital signal at a predetermined sampling rate into a compressed digital signal, and supplying the compressed digital signal, wherein the noise-shaping modulation is adaptive in response to at least one parameter.

Abstract: Estimating a compression gain obtainable in compressing a given audio signal, comprising extracting a signal power in a selected frequency band of the given audio signal, and obtaining an estimation of the compression gain by correlation with the extracted signal power.

Abstract: A digital low pass filter of the FIR type stores the input signal into register means with a plurality of taps. These taps are connected to address a look up table and the filtered output signal is derived from the output of the look up table. The filter may e.g. be used in systems where a one-bit direct stream digital (DSD) signal has to be requantized.

Abstract: A digital to analog converter for a multi bit digital input signal with a plurality of substantially equal conversion elements which are selected in accordance with a dynamic element matching algorithm. The dynamic element matching algorithm is adapted to the position of the conversion elements on the semiconductor chip to improve the shaping of the noise caused by the systematic, i.e. position dependent, errors of the conversion elements.