On-the-fly introduction of inter-channel delay in a pulse-width-modulation amplifier
US7492217B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 12, 2004 |
| Grant date | Feb 17, 2009 |
| Priority date | — |
| Expiry date | Mar 12, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2200/331
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A multiple-channel audio processor (10) and an associated plurality of power stages (22) in an audio system are disclosed. The audio processor (10) includes a plurality of audio amplifier channels (22), each of which includes a pulse-code-modulation (PCM) to pulse-width-modulation (PWM) conversion function (25), which generates PWM signals for application to the plurality of power stages (22). The audio amplifier channels (20) each also include an interchannel delay function (28) for delaying the PWM edges relative to other channels (20), for reducing noise. The audio amplifier channels (20) each also include delay adjust circuitry (32) for gradually increasing and decreasing the interchannel delay of the channel (20) on startup and shutdown. This permits a single control terminal (VALID) at the processor to globally enable and disable all of the power stages (22).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.