Semiconductor composite element, and method of detecting abnormal conditions in an inverter device having the element

摘要

A semiconductor composite element in which abnormal conditions of overcurrent, control supply voltage reduction and overheat are detected, and different abnormality signals are outputted according to the respective abnormal conditions thus detected. The semiconductor composite element includes: abnormal condition detecting circuitry for detecting the overcurrent and control supply voltage reduction of any one or all of the plurality of semiconductor switching elements and the overheat of the semiconductor composite element. An abnormality signal generating circuit is provided for producing different abnormality signals according to the respective abnormal conditions detected by the abnormal condition detecting circuitry.