Multirate Co-simulation of First Order Thermal Models in Electric Circuit Design

Abstract

Thermal effects influence the electrical behaviour of circuits more and more. Therefore it is necessary to take power dissipation and temperature evolution into account. In order to analyize large systems of integrated circuits, this has to be realized very efficiently. Thus we introduce a thermal network model consisting of 0D and 1D thermal elements approximating the full heat aspect, but keeping the system relatively small. After semi-discretization, this approach yields a coupled DAE system. According to the largely differing time scales, we outline the basics of a multirate co-simulation algorithm, which bases on an averaging technique. Its potential and feasibility is demonstrated on a simple, however, instructive testcircuit. As an outlook we discuss the application to thermal models of SOI-chips.