| 摘要 |
PURPOSE:To limit a shortcircuiting current when a transistor is turned to ON by connecting a parallel circuit of an oversaturation reactor and a resistor in series with a switching transistor. CONSTITUTION:The voltage of an output terminal 20 is compared with a reference voltage, fed back to the base of a transistor (Tr) 2, controlled to be turned ON and OFF to stabilize the voltage of an output terminal 20. An oversaturation reactor 8 is connected in series with the Tr2 with the switching regulator, and a resistor 9 is connected in parallel with the reactor. Thus, when the Tr2 is turned from ON to OFF, the current i8 of the reactor 8 abruptly drops to the current of the saturation point, and is attenuated by attenuation constant determined by the reactor 8 and the resistor 9. When the Tr2 is turned from OFF to ON, a current i9 is flowed to an output side circuit, and if the saturation time of the reactor 8 is set longer than the recovery time of a diode 5, the overcurrent can be limited. |
