Systems and methods for providing multi channel pulse width modulated audio with staggered outputs
US7061312B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 12, 2004 |
| Grant date | Jun 13, 2006 |
| Priority date | — |
| Expiry date | Aug 5, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2200/331
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
Systems and methods for reducing the noise level in a multi-channel digital audio system by staggering the timing of the pulse-width modulation in the different channels and thereby reducing the magnitude and increasing the frequency characteristics of the generated switching noise. One embodiment comprises a multi-channel digital PWM amplifier in which the timing signals used by each channel's modulator are staggered to evenly space the switching edges of the generated PWM signals. An additional, complementary delay is implemented in each of the channels to equalize the total delay for each channel so that the outputs of the channels are synchronized. The different channels may be implemented on different chips, in which case the chips may be synchronized prior to staggering the signals processed in each of the channels.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.