Digital saturation handling in integral noise shaping of pulse width modulation
US7227487B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 14, 2005 |
| Grant date | Jun 5, 2007 |
| Priority date | — |
| Expiry date | Nov 14, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03M3/452
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An audio amplifier includes a digital signal processor (DSP) that contains a noise shaping quantizer having an integrating error amplifier. The integrating error amplifier contains integrators connected in a feedback loop, a summer supplied with an output of each of the integrators, and a saturation function module producing a saturation function. A multiplier is disposed between each pair of adjacent integrators. The multiplier receives a signal from one of the adjacent integrators and the saturation function and supplies a signal to the other of the adjacent integrators. The saturation function decreases the effect of all of the integrators except an integrator to which an input signal to the integrating amplifier is supplied using an input signal to and/or an output signal from the noise shaping quantizer. This permits the duty ratio of the output signal from the noise shaping quantizer to extend from 0% to 100%.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.