DC Motor Drive with GaN Power HEMTs under High Temperature Environment

We drove a DC motor with GaN insulated gate HEMTs (GaN IG-HEMTs) and Si IGBTs under high temperature, and investigated their switching characteristics. The Si IGBTs had a collector tail current at turn-off state and it increased with increasing the operation temperature. This indicates that the power dissipation of the Si IGBTs at high temperature is very serious problems. On the other hand, the GaN IG-HEMTs had no drain tail current at turn-off state and the characteristics at 250 ? were almost same with those at room temperature. From theses measurements, it is clear that the GaN IG-HEMTs are superior to Si IGBTs in a high temperature operation and a high frequency operation. The on-resistance was in proportion to the 2.48 power of the operating temperature, and this temperature dependence was explained from a temperature dependence of the carrier mobility in 2-dimensional electron gas (2-DEG) layer.