| 摘要 |
PROBLEM TO BE SOLVED: To provide a protection circuit capable of reducing the risk that a switching element breaks down because of loss beyond an allowable loss, while avoiding an increase in assembly man-hour due to fitting of a temperature sensor to the switching element and reliability deterioration, and to provide a battery pack with the protection circuit. SOLUTION: The protection circuit includes connection terminals 11 and 12, a switching part SW, a current detection unit 219, switching voltage detection units (217, 218 and 211) detecting a switch voltage value Vsw being a voltage across the switching part SW, a switch loss calculation unit 212 calculating a power loss in the switching part SW by multiplying a current value detected by the current detection unit 219 by the switch voltage value detected by the switching voltage detection unit, and a switch protecting part 213 limiting a current flowing in the switching part SW when a power loss calculated in the switch loss calculation unit 212 exceeds a loss threshold Wth. COPYRIGHT: (C)2011,JPO&INPIT |
