LED ballast power supply having digital controller
US8395329B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 26, 2010 |
| Grant date | Mar 12, 2013 |
| Priority date | — |
| Expiry date | Mar 11, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B45/48
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A power supply for an LED lamp has a set of coupled coils, primary-side power circuitry including a converter power switch for conducting input power, and secondary-side power circuitry including a dimming power switch. Power control circuitry includes converter control circuitry which generates a converter control signal for the converter power switch to maintain a desired undimmed level of lamp current at a normal operating value of a lamp voltage. Dimming control circuitry generates a dimming control signal for the dimming power switch to pulse-width modulate the lamp current at a duty cycle corresponding to a desired dimming. Operation of the converter control circuitry is modified during dimming to prevent an automatic increase of the lamp voltage in response to a decrease in lamp current, avoiding undesirable overshooting of the lamp current and providing more accurate and effective control over dimming operation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.