Patent ID: 6092927
Filing Date: 2000-07-25
Classification: G01K

Abstract:
A method for determining the temperature of a discrete power semiconductor from an analog integrated circuit that is copackaged with the power semiconductor on a heat sink, given a knowledge of the thermal capacitance of the power semiconductor and of the analog integrated circuit, the thermal resistance between the power semiconductor and the analog integrated circuit, the thermal resistance between the power semiconductor and the heat sink and the thermal resistance between the analog integrated circuit and the heat sink, the method comprising:determining the voltage across the power semiconductor and the current through the power semiconductor, thereby determining the power dissipated in the power semiconductor;determining the temperature of the analog integrated circuit;determining the heat sink temperature;using said thermal capacitances, heat sink temperature and thermal resistances to set coefficients of an asymptotic observer system;providing said voltage and current and the temperature of the analog integrated circuit to the asymptotic observer system; andproviding as an output from said asymptotic observer system said temperature of the discrete power semiconductor.