CIRCUIT FOR LIGHTING HID LAMP

摘要

A lighting circuit for starting the discharge of an HID lamp at the lowest lighting voltage corresponding to the characteristics of the HID lamp so as to prevent damage to the main circuit by checking for the insulation of the HID lamp and the lighting circuit before lighting the HID lamp. The lighting circuit has a control unit (C) comprising insulation checking means for confirming if current does not flow when a predetermined voltage is applied to a main circuit (2) before the starting voltage is applied to the HID lamp (1) and a lighting voltage varying control means for stepwise increasing the secondary voltage outputted from a step-up transformer (10) of a starting circuit (3) after the insulation is confirmed.