| 摘要 |
PURPOSE: To obtain a switching regulator in which the power loss, of an inrush- current preventing resistor, generated in the rise of a power-factor correction circuit is eliminated so as to prevent the resistor from being damaged. CONSTITUTION: In a switching regulator, an AC input is rectified, a capacitor is connected, via a power-factor correction circuit 31, from a parallel circuit by a resistor and by a switching element for bypass switching, both ends of the capacitor are used as inputs of a converter circuit, and electric power which is output from a second winding at a main transformer used for the converter circuit is controlled. In the switching regulator, the switching element for bypass switching is turned on at the same timing as the operating instruction of the power-factor correction circuit, and it is provided with an inrush-current preventing circuit system which short-circuits a resistor 3. |
