Method and apparatus for controlling a selectable voltage audio power output stage
US8068622B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 14, 2006 |
| Grant date | Nov 29, 2011 |
| Priority date | — |
| Expiry date | Sep 28, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F1/025
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for controlling a selectable voltage audio power output stage provides a mechanism for raising the selected power amplifier output voltage in time for the arrival of signal peaks to avoid clipping. Signal peaks may either be delayed by delaying an increase in volume control level or enabling signal compression for a predetermined time period, so that sufficient time is provided for the amplifier power supply to stabilize at a higher operating voltage when an increase of power supply voltage is selected. Alternatively, a signal level may be determined at an upstream source, such as a decoder or filter that provides information in sufficient advance of the arrival of the peaks, and used to control the power supply selection, so that the higher power supply voltage level is selected in advance of arrival of the signal peaks that would otherwise cause clipping at the power amplifier output.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.