| 摘要 |
PROBLEM TO BE SOLVED: To provide a compact inductor with reduced radiation noise in an inductor current.SOLUTION: A step-up voltage power supply is provided on ECU loaded on an automobile, for example. The step-up voltage power supply includes a step-up coil, a switching element and a current control unit 16. The current control unit 16 controls a switching element 12 to be switched on and off in a clamp period during which an inductor current flowing through the step-up coil is clamped to a preset peak setting current, using a clock signal CK1 having a higher frequency than a pulse signal SPL, whereas in a non-clamp period, controls the switching element to be switched on and off using the pulse signal SPL. As such, the current control unit controls the switching element to be switched on and off to control the inductor current flowing through the step-up coil.SELECTED DRAWING: Figure 2 |
