| 摘要 |
<p>PURPOSE:To safely use a memory by providing plural voltage checking circuits for a battery, and detecting whether the battery deteriorates or charging is insufficient. CONSTITUTION:A battery 12 is chacked by comparing the voltage of the battery 12 with a reference voltage at 20% of the fully charged voltage in a first voltage checking circuit 13, and by comparing it with the reference voltage at 80% of the fully charged voltage in a second voltage checking circuit 14. That is, whether or not the capacity of the battery 12 is at <80%, and whether or not it is at <20% are checked. When the capacity of the battery 12 is at <20%, a battery error signal is generated from the checking circuit 13. Thus, the deterioration of the battery 12 is detected. On the other hand, when the capacity of the battery 12 is at <80%, an under-charging signal is generated from the checking circuit 14. Thus, the charging insufficiency of the battery 12 can be detected.</p> |
