| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a discharge lamp lighting device, lighting a discharge lamp load with a high frequency, attaining excellent safety, and cost and size reductions by detecting coming-off of one end a filament terminal at starting and detecting the end-of-life of a discharge lamp. <P>SOLUTION: The discharge lamp lighting device 10 includes: an inverter circuit 11 that converts a DC voltage into a high-frequency voltage; a resonance circuit 12; an inverter control circuit 13; a resistance voltage-dividing circuit 14; a bypass capacitor C5 for AC bypass; a DC current source I1 that inputs a DC bias into the bypass capacitor C5; a first abnormal-load detection circuit EL1 that lowers or stops high-frequency power supply into a discharge lamp FL when it is detected that a voltage across the bypass capacitor C5 exceeds a first reference voltage; and a second abnormal-load detection circuit EL2 that lowers or stops high-frequency power supply to the discharge lamp FL when it is detected that a voltage across the bypass capacitor C5 is under a second reference voltage. <P>COPYRIGHT: (C)2012,JPO&INPIT |
