| 摘要 |
PROBLEM TO BE SOLVED: To provide a control circuit and a switching power supply therewith which implement stable control and reduced standby power of the switching power supply.SOLUTION: In a light load condition in which the value of an output current of the switching power supply is not more than a first current value, a first control section performs first control of detecting a control voltage and controlling a switching action of a switch to bring the value of the control voltage to a first voltage. In a steady load condition in which the value of the output current of the switching power supply is more than the first current value, on the other hand, a second control section performs second control of detecting an output voltage on an output section side of the switching power supply and controlling the switching action of the switch to bring the value of the output voltage to a second voltage. A replenishment control section performs the control of turning on a power replenishment switch to step up the control voltage to the first voltage if the control voltage becomes less than the first voltage during the second control, and turning off the power replenishment switch after the control voltage becomes not less than the first voltage, and performs the control of turning off the power replenishment switch during the first control. |
