Dimmer multi-fire to increase direct AC LED device efficiency
US10405392B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 16, 2018 |
| Grant date | Sep 3, 2019 |
| Priority date | — |
| Expiry date | Apr 16, 2038 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B20/30
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A direct AC LED lighting device is provided with a controller that switches off a bleeder circuit following an initial rising edge for a post diode bridge voltage. The controller measures a first delay between a zero crossing for the post diode bridge voltage and the initial rising edge to estimate a triggering voltage for a leading edge dimmer switch. The controller determines a second delay following the initial rising edge responsive to the estimate of the triggering voltage. The controller may thus switch on the bleeder circuit at an expiration of the second delay so that bleeder circuit is only on for a duration sufficient to develop a voltage difference across the leading edge dimmer switch to equal the triggering voltage just as the post diode bridge voltage satisfies an LED threshold voltage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.