THERMAN examples

Analysis of a hybrid integrated circuit. The module is realized on a ceramic substrate. Heat removal from the hybrid module is realized basically by the wire leads of the package. This is modeled by heat-removing shapes describing the bonding pads of the circuit at the bottom part of the layout. The draining effect can be seen in the 2D temperature maps, on the vertical cross-sectional plot of the temperature distribution as well as on the 3D axonometrical view of the temperature distribution.

Resistors are realized by thick film printing in the circuit - they are considered by rectangular dissipating shapes. Transistors mounted onto the substrate are described in THERMAN by the compact model of their package (type SOT23), taken from the default package library. These packages have three footprints. Its is well demonstrated by the calculated temperature maps that significant amount of heat is driven from the junction via the package footprints into the substrate. During the interactive presentation of the steady-state results junction and footprint node temperatures of the package model are shown (at the cursor location) as well as the substrate temperature (in the right hand side display field).

Transient step responses have been calculated too. One can obtain such heating curves for any of the dissipating shapes as well as for any node of the dynamic compact package models.

Analysis of a 4 layer silicon structure (stacked chips). There are rectangular dissipaters on each layer. This picture shows the presentation of the steady-state results, regarding the top surface of the third layer. The dissipater on the selected layer is drawn with white.

Courtesy of TIMA Laboratory, Grenoble, France

This is a simulation example which highlights an important feature of THERMAN: in case of simple dissipating shapes only the execution time of a steady-state or AC simulation is independent of the layout complexity. This snapshot was taken at the TIMA Laboratory (Grenoble, France) where research concerning thermal simulation of large VLSI circuits is being done. In this case THERMAN was integrated into a widely used IC design framework. The chip layout taken from the design framework was flattened and converted into THERMAN's input format. Dissipation values assigned to standard cells or macro blocks were set proportional to the toggle count of the element in question.

See some more details about this topic here...

Analysis of a printed circuit board - different ways of presenting the results. The green rectangular shapes in the picture on the left are the outlines of the compact models of IC packages on the board. Compact models of packages can be selected from a user extendable library. The picture on the right shows the same simulation results in a 3D representation. The parameters of the view (viewing angle, height) can be changed.

Calculation of the thermal dominance map - the goal of such an analysis is to identify which regions of a PWB is controlled by which components. This analysis option of THERMAN prepares a map that shows the regions dominated by a given component. This dominance means, that the temperature of the given region is basically determined by the dominating component. Of course the dominance depends on the actual dissipation distribution.

THERMAN's graphical user interface allows the display of such a dominance map over the steady state temperature distribution. As the cursor is moved, the label of the dominating component and the area influenced is shown. Colored dominance maps can be generated in the HTML log of the simulation results.

Analysis of the thermal couplings between the input and output stages of an operational amplifier IC. The left hand side shows the thermal Bode-plot of the thermal transfer impedance from transistor T1 to transistor T3 and T4. The picture on the right shows the time-constant spectrum of the T1-T3 thermal transfer impedance. The time-constant spectrum calculation of THERMAN is a unique feature, it is the basis of compact thermal modeling for the purpose of electro-thermal simulations.