| 摘要 |
PURPOSE:To provide a lighting device excellent in the starting characteristic at low temperatures by applying a pulse voltage higher than the general voltage at lighting when a cold cathode-ray tube is started. CONSTITUTION:The output of a converter 14 is in high level when non-reversal input voltage (+) is higher than reversal input voltage (-). The output of a saw-tooth wave oscillating circuit is inputted at the non-reversal input, and the charged voltage of a capacitor C by a fixed voltage DC power source 16 at the reversal input. Since the charge voltage of the capacitor C is raised together with the ON of the power source 16, a switching transistor 13 is ON/ OFF by the output voltage of a comparator 14, or the output of the power source 16 is ON/OFF. Thus, an inverter 12 is operated to generate a high pulse voltage once just after the input voltage is built up, and, thereafter, a low AC voltage is generated. Since this state is repeated until the charged voltage of the capacitor C becomes higher than the maximum voltage of the saw-tooth wave, a cold cathode-ray tube 11 can be surely lighted. |
