| 摘要 |
PROBLEM TO BE SOLVED: To provide a lighting control device capable of reducing the rush current caused by change of frequency. SOLUTION: After a lapse of a first time from the start of lighting of a backlight, a first switch is switched to a second oscillation circuit from a first oscillation circuit. After the lapse of a second time after the first time from the start of lighting, a second switch is changed-over to a PWM dimming circuit from a voltage dimming circuit. The voltage dimming circuit inputs a voltage of 20% or lower than the maximum voltage into an inverter circuit, after starting up to the second time. After the lapse of the second time, the PWM dimming circuit makes the duty ratio increase up to the set duty ratio in a stepwise manner. COPYRIGHT: (C)2008,JPO&INPIT |
