Dimming circuit for powering gas discharge lamps
US5457360A · kind A · utility
15Cited by
5References
13Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 10, 1994 |
| Grant date | Oct 10, 1995 |
| Priority date | — |
| Expiry date | Mar 10, 2014 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S315/04
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A ballast circuit uses an optocoupler to provide electrical isolation of the dimming control from the remainder of the ballast. The optocoupler is operated in the linear range to provide continuous dimming of the lamps. The circuit further uses a combination of diodes and a diode bridge to steer current from the current sensor during lamp out conditions so that the inverter will maintain operation at a low frequency, thereby maximizing the output voltage. A clamp winding is used to insure that the voltage does not exceed the DC rail voltage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.