| 摘要 |
PROBLEM TO BE SOLVED: To provide a secondary battery protective circuit capable of protecting a secondary battery by stopping charging when the secondary battery is in an over-discharging condition at the time of charging. SOLUTION: A charging stop control IC1 detects battery voltage at intervals of a prescribed time at the time of starting charging, determines it as the secondary battery 5 in an over-discharge condition if an increase in battery voltage by charging is small, and controls FET2 so as to be conducted. A second PTC12 is heated by conducting the FET2 to heat a first PTC element 11 subjected to thermal coupling for tripping. By the tripping of the first PTC element 11, a charging circuit of the secondary battery 5 is shut down, thus stopping charging. |
