Two level lighting ballast
US8749162B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 10, 2011 |
| Grant date | Jun 10, 2014 |
| Priority date | — |
| Expiry date | Oct 23, 2032 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B20/00
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A two level lighting ballast is provided, which includes a self-oscillating inverter circuit and a control circuit. The inverter includes an input; an output to selectively provide current to energize a lamp; a switching circuit operating at a switching frequency; a feedback transformer; and an impedance component. The feedback transformer is connected to the output, and drives the switching circuit based on the lamp current. The impedance component is connected in parallel with the feedback transformer, and is operated by the control circuit. When the control circuit enables the impedance component, the switching circuit operates in a first frequency range, and a first lamp current is provided. When the control circuit disables the impedance component, the switching circuit operates in a second frequency range, and a second lamp current is provided. The first frequency range is lower than the second, and the first lamp current is greater than the second.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.