Switching amplifier resolution enhancement apparatus and methods
US6509793B2 · kind B2 · utility
Inventor
Key dates
| Filing date | May 21, 2001 |
| Grant date | Jan 21, 2003 |
| Priority date | — |
| Expiry date | Jul 12, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F3/2171
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
Circuitry and methods increase switching amplifier resolution. Operation of the circuitry broadly relies upon selectively diverting a controlled portion of the output voltage, current, charge, or power from the load, the resolution of which is inversely proportional to the portion diverted. Although modulation of the diverted voltage or current may be effected by pulsewidth variance, analog modulation of voltage or current diversion may alternatively be utilized. Additionally, although current amplifiers are discussed for sake of simplicity, the technique is equally applicable to both voltage and current amplifiers. Multiple instances of the invention may also be scaled at contiguous resolutions to yield greatly improved system resolution. It has been found that accurate production of pulse widths approaching zero is the prime resolution-limiting factor of some switching amplifier topologies. This particular limitation results in very audible crossover distortion. The technique disclosed herein is particularly helpful in this instance, in that its activity opposes the existing amplifier output, balancing the composite output.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.