LED lighting system with a multiple mode current control dimming strategy
US7759881B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Mar 31, 2008 |
| Grant date | Jul 20, 2010 |
| Priority date | — |
| Expiry date | Mar 31, 2028 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B20/30
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A light emitting diode (LED) lighting system includes a controller to control current in one or more LEDs in response to a dimming level input. The LED lighting system implements a dimming strategy having two modes of operation that allow the LED lighting system to dim the LEDs using an active value of an LED current less than a full value LED current while maintaining continuous conduction mode operation. In an active value varying mode of operation, the controller varies an active value of the LED current for a first set of dimming levels. In an active value, duty cycle modulation mode of operation, the controller duty cycle modulates an active value of the LED current for a second set of dimming levels. In at least one embodiment, the active value of the LED current varies from a full active value to an intermediate active value as dimming levels decrease.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.