| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a reverse flow preventing means capable of preventing charging of a back-up power supply, as a reverse flow preventing means for a back-up power supply device consisting of a main power supply and the back-up power supply. <P>SOLUTION: The reverse flow preventing means of the main power supply is provided with a voltage regulator. In a usual operation for supplying a voltage from the main power supply to a load, the voltage regulator controls a voltage of the main power supply so that an inter-terminal voltage of a diode or a transistor to be used as the reverse flow preventing means for the back-up power supply can become zero. On the contrary, when the voltage of the main power supply becomes lower than the voltage of the back-up power supply, the voltage regulator is turned off to prevent a current from flowing from the back-up power supply to the main power supply. <P>COPYRIGHT: (C)2008,JPO&INPIT</p> |
