| 摘要 |
PROBLEM TO BE SOLVED: To provide the lighting device for a discharge lamp, which prevents a MOSFET consisting of a rectangular wave circuit from being ruptured, and also prevents a discharge lamp at its life end from being lighted for a long time. SOLUTION: The lighting device for a discharge lamp is provided, which is made up of a rectifying circuit 2 converting commercial electric power into direct current, a booster inverter circuit 3 boosting the output voltage of the aforesaid rectifying circuit 2, a step down inverter circuit 4 making the output of the aforesaid boosting inverter circuit 3 a definite electric power, and of a rectangular wave circuit feeding the output of the aforesaid step down inverter circuit 4 to a discharge lamp as rectangular wave voltage. Four MOSFETs consisting of the aforesaid rectangular wave circuit is formed out of a MOSFET module 5X where the aforesaid four MOSFETs are integrated, concurrently, the MOSFET module 5A is bonded to a metallic case 31, and furthermore, a thermal protector 32 detecting the increment of temperature of the aforesaid MOSFET module 5X, is held onto the surface of the MOSFET module 5X by a presser fitting 33. |
