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:
Apr. 14, 2009
Filed:
Mar. 25, 2004
Matthias Wendt, Wuerselen, DE;
Iain Mosely, Pangbourne, GB;
F. Javier Esguevillas, Cambrils, ES;
NXP B.V., Eindhoven, NL;
Abstract
Recently, the use of class D audio amplifiers has become more and more widespread. In contrast to the generally employed class AB linear amplification technology, class D allows for improved efficiency. However, the class D principle is known for its poor distortion characteristics. According to the present invention, switching delays of the end stage () are measured and used for compensating distortions caused by the dead time of the end stage (). This is done by modifying the switching delay of the power stage. In this way, the output pulse duration is corrected to reflect the input duty cycle. Advantageously, variations in the switching-time due to device property spread, aging, current and temperature may be compensated.