Digital amplifier
US7518450B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 25, 2004 |
| Grant date | Apr 14, 2009 |
| Priority date | — |
| Expiry date | Mar 31, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2200/03
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
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 (6) are measured and used for compensating distortions caused by the dead time of the end stage (6). 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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.