Lighting apparatus
US6057651A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 24, 1998 |
| Grant date | May 2, 2000 |
| Priority date | — |
| Expiry date | Aug 24, 2018 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B20/30
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A lighting apparatus includes a full-wave rectifier circuit for rectifying an AC voltage from a commercial power source, a smoothing condenser connected is series with an inductor and a diode between output terminals of the full-wave rectifier circuit, a light source unit containing a series circuit of light emitting diodes and connected in parallel with the smoothing condenser, a MOSFET connected in series with the inductor between the output terminals of the full-wave rectifier circuit, and a control circuit for performing switching control of the MOSFET. In particular, the control circuit is constituted such that a voltage across the smoothing condenser is set higher than a peak of an input voltage input to the smoothing condenser through the diode and equal to a total sum of forward voltage drops of the light emitting diodes at a time of igniting the light source, under the switching control.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.