| 摘要 |
PURPOSE:To remove restriction on the control of an output voltage, by providing an auxiliary switching transistor and by applying a signal, which is obtained by inverting the driving signal of a main switching transistor to the base. CONSTITUTION:The collector and the base of an auxiliary switching transistor 20 are connected to the base of a main switching transistor 13 and a terminal 2, respectively. An intermittent signal (a) transmitted from a pulse width control circuit 5 is applied to resistances 16 and 19 and diodes 17 and 18, and a signal (e) is applied to the base of the auxiliary switching transistor 20. Therefore, the opened auxiliary switching transistor 20 is closed. As the result, accumulated electric charge in the main switching transistor is extinguished as a collector current (f) of the auxiliary switching transistor 20. |
