| 摘要 |
PURPOSE:To provide such a switching power unit that the potentials +V and-V at the power unit can be prevented from becoming too high and too low, respectively, and the efficiency of the power unit is improved and, in addition, a loading device sharing a constitution with the power unit. CONSTITUTION:When the terminal voltage of a capacitor 108 increases and the potential at a switching power unit +V exceeds a prescribed value, a switch control means 28 turns on a switching element 18 for a fixed period of time so as to make an electric current to flow to an inductor 30. After the fixed period of time, the switching element 18 is turned off and the inductor 30 supplies a capacitor 110 with an electric current. When the potential -V at the power unit drops, the control means 28 turns on another switching element 16. In case the potential +V becomes higher than a prescribed value and the potential -V becomes lower than another prescribed value, the control means 28 turns on both the switching elements 18 and 16. |
