| 摘要 |
PROBLEM TO BE SOLVED: To provide a switching regulator capable of suppressing an excessive increase in an output power-supply voltage while maintaining a voltage required for driving a switching element.SOLUTION: A switching regulator 30 includes a bootstrap circuit 7 and a charge-pump circuit 8. When an input power-supply voltage VIN falls below a predetermined threshold value, a low-voltage on control section 11 generates a step-up voltage 3(VIN-VF) by operating the charge-pump circuit 8 and supplies the voltage to a driving circuit 10. When the power-supply voltage VIN exceeds the predetermined threshold value, the low-voltage on control section 11 stops the operation of the charge-pump circuit 8 and supplies a step-up voltage 2VIN by the bootstrap circuit 7 to the driving circuit 10. |
