Exploiting electrothermal oscillations for identifying MOSFET thermal parameters

Electrothermal oscillations in electronic circuits are in general regarded as parasitic dynamic phenomena. This paper shows how these phenomena may be exploited to identify the value of thermal resistance and capacitance of t he RC network modelling heat diffusion. Measurement of the period of oscill ations and bifurcation analysis of the stability of the equilibrium point a re two approaches that may possibly lead to a reasonable estimate of these parameters. In this paper, we present both methods applied to two specific MOSFET circuits. In particular, the oscillation period of a current-mirror circuit and bifurcation analysis of a simple one-MOSFET circuit are analyse d in detail. For the bifurcation analysis approach, theory and experimental results are successfully compared to simulation in order to validate the p roposed model. (C) 2001 Elsevier Science Ltd. All rights reserved.