Patent ID: 9209697
Filing Date: 2015-12-08
Classification: H02M,Y02B,Y02P

Abstract:
1. A switching power-supply device comprising: a non-insulated converter arranged to boost an input power supply voltage, which is input to the non-insulated converter, and output a direct-current voltage; and an insulated bridge converter into which the direct-current voltage output from the non-insulated converter is input and that is arranged to output a direct-current voltage to a load; wherein the insulated bridge converter includes: the non-insulated converter includes: the switching power-supply device further includes: when the input power supply voltage is less than a threshold value, which is greater than a voltage at a time of a rated operation and less than a maximum value of an operation input voltage, the PWM control circuit and the switching control circuit performs the rated operation; when the input power supply voltage is equal to the threshold value or greater, the PWM control circuit stops switching control of the third switch element; and the switching control circuit controls at least one of an on-duty ration and a switching frequency of the first switch element and the second switch element.