Patent ID: 7030569
Filing Date: 2006-04-18
Classification: H05B

Abstract:
1. A method of improving a start up operation of a direct drive CCFL circuit, the method comprising: driving a CCFL of the direct drive CCFL circuit at a switching frequency substantially different than a resonant frequency of the CCFL circuit; and allowing the switching frequency to approach the resonant frequency in a controlled manner, wherein allowing the switching frequency to approach resonant frequency in a controlled manner includes: monitoring an input voltage and a current of the CCFL to determine whether the switching frequency is incrementally changed to approach resonant frequency, wherein monitoring includes: determining whether the input voltage is equal to or less than a predetermined intermediate voltage and an output voltage of the CCFL, which is proportional to the current of the CCFL, is less than a predetermined low voltage; and if so, then incrementally changing the switching frequency to approach resonant frequency.