The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 01, 2010
Filed:
Jul. 25, 2007
Jack B. Andersen, Cedar Park, TX (US);
Peter G. Craven, Thakeham, GB;
Michael A. Kost, Cedar Park, TX (US);
Daniel L. W. Chieng, Austin, TX (US);
Larry E. Hand, Meridian, MS (US);
Wilson E. Taylor, Austin, TX (US);
Jack B. Andersen, Cedar Park, TX (US);
Peter G. Craven, Thakeham, GB;
Michael A. Kost, Cedar Park, TX (US);
Daniel L. W. Chieng, Austin, TX (US);
Larry E. Hand, Meridian, MS (US);
Wilson E. Taylor, Austin, TX (US);
D2Audio Corporation, Milpitas, CA (US);
Abstract
Systems and methods for performance improvements in digital switching amplifiers using low-pass filtering to reduce noise and distortion. In one embodiment, a digital pulse width modulation (PWM) amplifier includes a signal processing plant configured to receive and process an input audio signal. The amplifier also includes a low-pass filter configured to filter audio signals output by the plant. The filtered output of the plant is added to the input audio signal as feedback. The plant may consist of a modulator and power switch, a noise shaper, or any other type of plant. An analog-to-digital converter (ADC) may be provided to convert the output audio signal to a digital signal. Filtering may be implemented before or after the ADC, and a decimator may be placed after the ADC if it is an oversampling ADC.