DISCHARGE LAMP LIGHTING DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a discharge lamp lighting device of high safety that detects the ground positively. SOLUTION: A control part 5 changes the output of a DC-DC converter 6 into an arbitrary value and outputs a control signal for turning on switching elements Q1, Q3 out of switching elements Q1-Q4 of a full bridge circuit of the DC-AC converter 7 to detect the ground through a detecting part 4. Or the control part outputs a control signal for turning on two switching elements Q1, Q2 or Q3, Q4 out of the switching elements Q1-Q4 of the full bridge circuit so as to short-circuit the output of the DC-DC converter 6 through the detecting part 4, to detect the ground through the detecting part 4.