| 摘要 |
<p>PURPOSE:To effectively back up a memory regardless of the types of memories to be backed up by using a battery at high voltage capacity, and providing a power source to charge the battery. CONSTITUTION:A battery BAT at the high voltage capacity is used, and a power source at +12[V] to charge the battery BAT is provided. After the input of the power source, when the input voltage amounts to +5[V] and it exceeds the reference voltage of voltage detecting circuits 7, the output of the voltage detecting circuit 7 is turned off, a transistor (Tr) 1 is turned off, and power supply to an output terminal VB is switched from the battery BAT to the power source +5[V]. Simultaneously the battery BAT is charged by the power source +12[V]. Thus, by determining the battery and the charging power source according to the types of the objective memories, the memory in any type can be effectively backed up.</p> |
