Heat transfer through a semiconductor module
Semiconductors / Fundamental Components / Thermal
The Foster Thermal Model block represents heat transfer through a semiconductor module. The figure shows an equivalent circuit for a fourth-order Foster Thermal Model block. Tj is the junction temperature and Tc is the base plate temperature.
A Foster thermal model contains one or more instances of Foster thermal model elements. The figure shows an equivalent circuit for a Foster thermal model element.
The number of thermal elements is equal to the order of representation. For a first order model, use scalar block parameters. For an nth order model, use row vectors of length n. Other terms that describe a Foster thermal model are:
Partial fraction circuit
The defining equations for a first-order Foster thermal model element are:
Cthermal is the thermal capacity.
τ is the thermal time constant.
Rthermal is the thermal resistance.
QAB is the heat flow through the material.
TAB is the temperature difference between the material layers.
Thermal resistance values, Rthermal ,
of the semiconductor module, specified as a vector. The default value
[ 0.0016 0.0043 0.0013 0.0014 ]
Thermal time constant values, τ, of
the semiconductor module, specified as a vector. The default value
[ 0.0068 0.064 0.32 2 ]
The block has the following ports:
Thermal conserving port associated with the semiconductor junction.
Thermal conserving port associated with the base plate junction.
 Schütze, T. AN2008-03: Thermal equivalent circuit models. Application Note. V1.0. Germany: Infineon Technologies AG, 2008.