| 摘要 |
PROBLEM TO BE SOLVED: To provide an LED drive by which a high-luminance LED can be efficiently lit, for example, without requiring a large-capacity capacitor or a large-electromotance solar battery. SOLUTION: The LED drive is provided with an electric double-layer capacitor 10 which is used as a primary power supply; a step-up DC/DC converter 16 which has the function of boosting the voltage of the electric double-layer capacitor 10, outputting it to the secondary side, controlling ON and OFF of the secondary boosted output voltage and controlling the both ends voltage of resistor circuits to a constant level; a plurality of LEDs 20 which are connected with the secondary output of the step-up DC/DC converter 16, and are connected in series with each other; resistor circuits 22, 23 and 24 which are connected between the LED of the last stage of the plurality of LEDs and the ground whose resistance value is variable; and resistance value control circuits 25, 26, 27 and 28 which detect the voltage of the electric double-layer capacitor 10, and change the resistance value of the resistor circuits according to the detected output. COPYRIGHT: (C)2008,JPO&INPIT
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