07288902 is referenced by 224 patents and cites 26 patents.

A method and system allow a lighting device having light sources with multiple color temperatures to vary a color temperature of the lighting device in response to changing dimming levels. The light sources are non-incandescent light sources, such as light emitting diodes and/or gas-discharge lights. A dimmer circuit provides a dimming signal that indicates a selected dimming level. The lighting device includes a light source driver and a light source driver controller that cooperate to vary drive currents to the light sources in response to the selected dimming level. By varying the drive currents in different relative amounts, the color temperature of the lighting device changes in response to dimming level changes. In at least one embodiment, changes in the color temperature of the lighting device in response to the dimming level changes simulates the color temperature changes of an incandescent light source.

Title
Color variations in a dimmable lighting device with stable color temperature light sources
Application Number
11/695023
Publication Number
7288902 (B1)
Application Date
April 1, 2007
Publication Date
October 30, 2007
Inventor
John L Melanson
Austin
TX, US
Agent
Kent B Chambers
Hamilton & Terrile
Assignee
Cirrus Logic
TX, US
IPC
G05F 1/00
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