| 摘要 |
PURPOSE:To suppress fluctuation of output voltage due to fluctuation of input voltage and to reduce power consumption by connecting outputs from first and second constant voltage means with a common load and disabling the second constant voltage means when the first constant voltage means is providing power to the load. CONSTITUTION:First constant voltage means, i.e., a converting section 7a, is connected with a load L and a second constant voltage means, i.e. a converting section 7b, is also connected with the load L. Output from the converting section 7a is set lower than the output from the converting section 7b. Power consumption at the converting section 7a is lower than that at the converting section 7b. The converting section 7b is disabled when the converting section 7a is providing a constant voltage. A constant voltage is provided normally from the converting section 7a and a constant voltage is provided from the converting section 7b having high level upon occurrence of abnormality. By such arrangement, sufficient margin can be provided for the output voltage against the fluctuation of input source voltage and power consumption can be reduced. |
