Experimental evaluation of IGBT junction temperature measurement via peak gate current

Temperature sensitive electrical parameters allow junction temperature measurements on power semiconductors without modification to module packaging. The peak gate current has recently been proposed for IGBT junction temperature measurement and relies on the temperature dependent resistance of the internal gate resistor. In this paper, infra-red measurements are used to evaluate the validity of this method. Temperature measurements are made on IGBTs operating under steady state power dissipation. The peak gate current is found to provide a temperature slightly overestimating the temperature of the gate pad. Consequently, a consideration of chip geometry and location of the gate pad is required before interpreting temperature data from this method. Results are also compared with a traditional electrical temperature measurement method: the voltage drop under low current.