An abnormality diagnostic device and method for a MOSFET switch element included in a rechargeable battery pack is provided that makes it possible to determine whether there exists a short circuit abnormality (fusion) in a MOSFET switch element that causes...

The present disclosure is generally directed to a plurality of solid state switches of varying periphery sizes connected in series between a power source and a load. A built-in test circuit senses an overvoltage condition across one or more of the solid st...