| 摘要 |
PROBLEM TO BE SOLVED: To suppress increase in power consumption of an LED backlight drive unit resulting from LEDs widely varied in voltage drop in a backlight device including a backlight module having a plurality of LED chains in which a plurality of LED light sources are serially connected, and a backlight driving IC having an FET switch for driving the plurality of LED chains. SOLUTION: A resistance element 115 is serially connected to a cathode terminal of the final-stage LED (or an anode terminal of the first-stage LED) of an LED chain 116, and the resistance element 115 is configured so that the resistance value is changeable according to variation in voltage drop of serially connected LEDs, so that the resistance value of a resistance element connected to an LED chain with large voltage drop is reduced, while the resistance value of a resistance element connected to an LED chain with small voltage drop is increased. Accordingly, the power which was conventionally wasted as heat generation in the backlight driving IC can be dispersed to the resistance elements. COPYRIGHT: (C)2011,JPO&INPIT |
