Fluorescent lamp dimmer with multi-function integrated circuit
US8358078B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Sep 30, 2008 |
| Grant date | Jan 22, 2013 |
| Priority date | — |
| Expiry date | Jun 1, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B41/28
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
In one embodiment, a fluorescent lamp dimming circuit includes power factor correction control, dimming control, and switching devices. The power factor correction control may be connected to power factor correction circuitry that produces a regulated DC buss. The dimming control circuit may be connected to the input of the fluorescent lamp dimming circuit for producing a driver signal whose frequency varies depending on the input voltage waveform perhaps as modified by a dimmer. The control circuit may produce a drive signal with a duty cycle profile to drive switching devices. The switching devices invert the DC buss voltage to an AC voltage waveform for driving a resonant tank circuit. The resonant tank circuit may include an inductance, a capacitance, and the impedance of a fluorescent lamp. The AC voltage waveform when applied to the resonant tank circuit may cause the fluorescent lamp to dim based on the dimmer setting.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.