| 摘要 |
PROBLEM TO BE SOLVED: To provide a lighting device for a discharge lamp needing only capacitors of comparatively small capacitance as charging capacitors in an auxiliary power supply circuit. SOLUTION: A bypass circuit 36a is provided for a high-side switching element 11. A bypass circuit 26a has a bypass line 23 for bypassing the switching element 11 from the gate side to the source side and series-connected reference diodes 24, 25 in the bypass line 23. The reference diode 24 is disposed on the gate side while the reference diode 25 on the source side with their respective cathodes arranged toward the gate side. A gate-voltage extraction circuit 36a comprises a bypass line 31 for bypassing the switching element 11 from the gate side to the source side and a switching element 32 inserted in the bypass line 31, and, when the switching element 12 is turned on, the switching element 32 is turned on to allow a gate current of the switching element 11 to flow to the source side. |
