| 摘要 |
PROBLEM TO BE SOLVED: To provide a DC-DC converter in which a current does not backflow from an output capacitor to an output-side coil at the time of light load.SOLUTION: In a DC-DC converter that is a synchronous rectifying SEPIC, a control circuit CC outputting a control signal controlling on and off of MOS transistors Nch and Pch is provided with a determination section outputting a determination signal indicating the state of the reduction when a voltage value indicating the total sum of the current value of a current iflowing through a coil Land the current value of a current iflowing through a coil Lis smaller than a predetermined reference voltage Vref1, and turns off the MOS transistor Pch at the time of rectifying operation according to the determination signal. The predetermined reference voltage Vref1 is achieved by a reference voltage source RVS1, and is a voltage according to a limit load value in which a load current does not backflow. |
