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Document Number
US Patent 6989807
Issued Date
January 24, 2006
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Abstract
A LED driving device includes a plurality of LEDs, a voltage detecting circuit, and a current switching circuit. When the voltage detecting circuit detects the different voltage level of power source without coupling to a filtering capacitor, it sends a signal to the current switching circuit and then the current switching circuit is automatically activated to electrically rearrange the configuration of LEDs with a predetermined current value by lighting the greatest number of LEDs that improving the power factor and efficiency.
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Number of Claims:
16
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Published
January 24, 2006
Application Number
10/440,117
Filed
May 19, 2003
US Classification
345/82   315/291 315/307 323/364 340/815.4 340/815.45 340/815.52 345/83 345/84 345/98 372/38.03
Int'l Classification
G09G   3/32   (20060101)  
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USPTO Field of Search
345/82  
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Description
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