| 摘要 |
PROBLEM TO BE SOLVED: To provide a discharge lamp lighting device capable of obtaining stable protection operation of high detection sensitivity when an abnormality such as disconnection and damage occurs in a discharge lamp. SOLUTION: An inverter circuit 3 applies a high frequency high voltage to the discharge lamps 71 to 7n. A current detecting circuit 81 detects a current flowing in the discharge lamps 71 to 7n. A voltage detecting circuit 6 detects a voltage supplied to the inverter circuit 3. A protecting circuit 4 stops operation of the inverter circuit 3 when a current detecting signal VB detected by the current detection circuit 81 becomes below the voltage detecting signal VA detected by the voltage detecting circuit 6. A timer circuit 8 stops operation of the protecting circuit 4 during a prescribed time when a power source is switched on. COPYRIGHT: (C)2008,JPO&INPIT |
