DISCHARGE LAMP LIGHTING DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a discharge lamp lighting device capable of discriminating normal discharge of a discharge lamp from abnormal discharge thereof without being influenced by voltage variation of a D.C. power source nor causing malfunction. SOLUTION: This discharge lamp lighting device is equipped with: an inverter circuit for converting a direct current supplied from the D.C. power source into a high-frequency current; discharge lamp load circuits L100 and L110; peak-to-peak voltage detection circuits P100 and P110 for detecting peak-to-peak voltages generated in secondary windings 5a, 5b, 9a and 9b formed in choke coils 5 and 9 of the load circuits L100 and L110; a determination circuit C100 for comparing the peak-to-peak voltages detected by the detection circuits P100 and P110 with a voltage obtained by dividing the voltage of the D.C. power source 1 to output a stop signal for stopping oscillation of the inverter circuit when the peak-to-peak voltages are larger; and a holding circuit H100 for stopping the oscillation of the inverter circuit by the stop signal of the determination circuit C100 and for continuing the stop state. COPYRIGHT: (C)2004,JPO&NCIPI