| 摘要 |
PURPOSE:To prevent unbalance in switching and generate stabilized lighting condition by connecting a capacitor in parallel with a switching element, connecting a resistance in series to the same switing element, and smoothening the noise. CONSTITUTION:A capacitor 12 is connected between the collector and emitter of a control transistor 11, while a resistance 13 is connected with the collector of the same transistor 11. In the condition with high density mounting, noise from the middle point A line side may be included in the base potential VB of the transistor 11. The output of the transistor 11 is, however, smoothened and attenuated by the capacitor 12 and resistance 13 so that influence of the noise is inhibited, and therefore the collector current Ic of the transistor 11 becomes flat. Accordingly no difference appears between the drive currents of two switching transistors Q1, Q2 of a self-exciting inverter 1, so that no unbalance is generated in the switching motion, and a discharge lamp 5 can be lighted up with stabilized switching motions. |
