Diagnosis Circuit of Parallel-Structure Mosfets Including Mux and Diagnosis Method Using the Same

A circuit and diagnosis method capable of individually diagnosing abnormality of a plurality of internal FETs constituting a MOSFET provided between a secondary battery pack and an electric vehicle. Voltage at both ends of each of the internal FETs is measured while individually turning ON/OFF the internal FETs, and is compared with a diagnosis table in order to determine abnormality thereof.