DISCHARGE LAMP LIGHTING DEVICE, AND LIGHTING EQUIPMENT AND LIGHTING SYSTEM USING THE DEVICE

摘要

A level shift IC (3b) of a power supply interrupting part (3) interrupts power supply to a smoothing capacitor (4) when an interruption signal (Sa) is inputted for a time (T) from a timer circuit (8) while a discharge lamp (7) is lighted. While the interruption signal (Sa) is being inputted, a comparator (10) detects that a detection signal (Sb) of a capacitor voltage is reduced to be lower than a reference voltage (Vr1). Then, the end of a lifetime of the smoothing capacitor (4) is notified and a main control circuit (6) suppresses output of an inverter main circuit (5).