Driving scheme for minimizing ignition flash
US5680017A · kind A · utility
16Cited by
6References
14Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | May 3, 1996 |
| Grant date | Oct 21, 1997 |
| Priority date | — |
| Expiry date | May 3, 2016 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S315/04
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A ballast for powering a lamp at deep dim levels. Driving circuitry includes a feedback loop which compares a desired dim level to a signal representing actual lamp power consumption. The loop is closed once the signal representing actual lamp power consumption equals the desired dim level. During ignition, a switch in response to the lamp voltage reaching or exceeding a predetermined threshold opens the feedback loop. The feedback loop is closed once the lamp has been ignited. By closing the loop as soon as the lamp has been ignited, ignition flash is minimized.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.