Title :
Combination of thermal subsystems modeled by rapid circuit transformation
Author :
Gerstenmaier, Y.C. ; Kiffe, W. ; Wachutka, G.
Author_Institution :
Siemens AG, Muenchen
Abstract :
This paper will deal with the modeling-problem of combining thermal subsystems (e.g. a semiconductor module or package with a cooling radiator) making use of reduced models. The subsystem models consist of a set of Foster-type thermal equivalent circuits, which are only behavioral models. A fast algorithm is presented for transforming the Foster-type circuits in Cauer-circuits which have physical behavior and therefore allow for the construction of the thermal model of the complete system. Then the set of Cauer-circuits for the complete system is transformed back into Foster-circuits to give a simple mathematical representation and applicability. The transformation algorithms are derived in concise form by use of recursive relations. The method is exemplified by modeling and measurements on a single chip IGBT package mounted on a closed water cooled radiator. The thermal impedance of the complete system is constructed from the impedances of the subsystems, IGBT-package and radiator, and also the impedance of the package can be inferred from the measured impedance of the complete system.
Keywords :
curve fitting; equivalent circuits; insulated gate bipolar transistors; power bipolar transistors; recursive functions; reduced order systems; thermal management (packaging); Cauer circuits; Foster-type thermal equivalent circuits; cooling radiator; mathematical representation; physical behavior; rapid circuit transformation; recursive relations; reduced models; single chip IGBT package; thermal impedance; thermal subsystems model; Circuits; Cooling; Electronic packaging thermal management; Heat transfer; Impedance; Insulated gate bipolar transistors; Power system modeling; Semiconductor device measurement; Temperature; Thermal resistance;
Conference_Titel :
Thermal Investigation of ICs and Systems, 2007. THERMINIC 2007. 13th International Workshop on
Conference_Location :
Budapest
Print_ISBN :
978-2-35500-002-7
DOI :
10.1109/THERMINIC.2007.4451758