A New PSPICE Power MOSFET Subcircuit with Associated Thermal Model

摘要

The design of power converters with ever-increasing power density and severe thermal constraints are posing new challenges to modem power semiconductors. As a result, thermal optimization and verification are getting more important than electrical modeling. A new Pspice model is presented here which allows calculation of a MOSFET's chip temperature in response to a transient. Thermal impedance data required by this model are available from any manufacturers' datasheet. This paper describes a novel PSPICE MOSFET subcircuit associated to a thermal model, that is, designed to have a dynamic link between the component's thermal and electrical descriptions. The model developed provides a correlation to the thermal environment permitting, for example, the analysis and optimization of gate drives, loads, and heatsinks. It can be useful to improve heatsinks design that is often hampered by the difficulty in predicting power losses owing to parameters' production spread and to their strong dependence.