Closed-loop/dimming ballast controller integrated circuits
US6008593A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 12, 1998 |
| Grant date | Dec 28, 1999 |
| Priority date | — |
| Expiry date | Feb 12, 2018 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S315/07
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A novel monolithic electronic ballast controller IC for driving two MOS gated power semiconductors, such as power MOSFETs or IGBTs, connected in a totem pole or half-bridge arrangement. Advantageously, the present invention provides programmable preheat time and current, programmable end-of-life protection, lamp fault protection, over-temperature protection. The first embodiment of the invention is a closed-loop ballast controller IC intended for multiple lamp configurations, with three current-sensing inputs and programmable lamp power. Closed-loop control is accomplished through phase control, or, more specifically, a phase-locked loop (PLL) around a resonant type output stage driving a fluorescent lamp. The second embodiment of the present invention has a similar architecture to that of the first embodiment, with some modifications which allow dimming down to low light levels.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.