DEVICE AND METHOD FOR DETECTING ABNORMALITY OF BACKUP BATTERY FOR MEMORY

摘要

PROBLEM TO BE SOLVED: To provide a device and a method for abnormality detection of a backup battery for a memory which accurately detects as abnormality a case wherein the battery voltage of the backup battery drops below the level needed for the operation of the memory. SOLUTION: The device is equipped with a voltage detection part 13 which detects a source voltage Vb, a battery voltage connection part 15 which decides that the backup battery 2 is connected when the value of a source voltage Vb is larger than a 1st threshold, and an abnormality detection part 14 which detects abnormality of the backup battery 2 when the value of the source voltage Vb is less than a 2nd threshold while it is decided that the backup battery 2 is connected. Abnormality is prevented from being detected by mistake like before even when the backup battery 2 is not connected and the case wherein the battery voltage of the backup battery 2 drops below the level needed for the operation of the memory 1 can accurately be detected as abnormality.