| 摘要 |
PURPOSE:To simplify the consititution of a circuit as a whole and to maintain the condition within a definite voltage fluctuation range even when a voltage is fluctuated by connecting plural switching elements in parallel, selecting one of them, conducting them, therefor, detecting voltage between terminals and executing a conduction control. CONSTITUTION:Even when control signals of control switching elements TH1-TH3 to be conducted according to the fluctuation of the voltage supplied to a load 2 are generated, if the control switching element to be conducted up to such a time is made non-conductive, the voltage between the terminals of the control switching element remains at zero, and thereby, the switching to the control switching element to be conducted next is no executed. Consequently, a short-circuit between taps is not generated by conducting plural control switching elements TH1-TH3. Moreover, all control switching elements TH1-TH3 are made non-conductive, and when the voltage between the terminals are changed from zero all, the switching to the next control switching element is immediately executed. Thus, by the simple constitution, the voltage can be stabilized with good efficiency. |
