| 摘要 |
PROBLEM TO BE SOLVED: To provide a discharge lamp lighting device basically operating in almost a boundary mode in stably lighting in a stationary state, capable of stably switching operation even in high impedance of a power source, and having a DC-DC conversion circuit which prevents the flow of excess current into a switching element. SOLUTION: In a discharge lamp lighting device having a DC-DC conversion circuit 2 as an output adjusting means, in such a condition that a discharge lamp 5 is stably lit in a stationary state, switching operation is conducted in such a boundary mode that a switching element 22 is switched off from an on state, and when current of a transformer 21 reaches almost zero, the switching element 22 is turned on again, and the upper limit and the lower limit are set in the on time of the switching element 22. |
