Electronic dimming ballast
US6452344B1 · kind B1 · utility
99Cited by
13References
31Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Feb 12, 1999 |
| Grant date | Sep 17, 2002 |
| Priority date | — |
| Expiry date | Feb 12, 2019 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S315/04
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An electronic dimming ballast has a parallel loaded resonant output circuit plus a combination of pulse width modulation and frequency variation to accomplish the dimming of compact fluorescent lamps. The ballast operates at a fixed frequency throughout a selected range of light levels, with dimming control being done completely by duty cycle variation over this range of operation, and then smoothly moves to a variable frequency as the light output moves outside the selected range, with both duty cycle and frequency variation being the means of lamp light output control outside the selected range.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.