## Evaluation of Temperature Curves Regarding Power Module Lifetime

Posted on 01 February 2020

All internal connections of power modules are subject to aging caused by temperature fluctuations. The fatigue of material as well as wear and tear is caused by thermal stress due to the different expansion coefficients of the connected materials. Module lifetime or respectively, the number of possible temperature [...]

## Thermal stacking of Power Modules

Posted on 14 January 2020

When thermally stacking several heatsinks, in particular in combination with larger power electronics assemblies, the reduction in coolant flow rate resulting from the increased pressure drop and pre-heating of the coolant for the "backward" units has to be considered in the calculations. Figure 1. a) Individual cooling; b) [...]

## Power Module Junction Temperature Calculation

Posted on 08 January 2020

Examples of power module junction temperature calculations for various operating conditions are given below. The following calculations make use of thermal equivalent circuit diagrams, a method that can be used in certain situations to simplify junction temperature calculations. For more complex situations, other calculation techniques must be employed.     Junction temperature during stationary [...]

## Thermal Equivalent Circuit Diagrams for Junction Temperature Calculations

Posted on 03 January 2020

The calculation of junction temperatures is based on simplified thermal equivalent circuit diagrams (Figure 1)  in which three dimensional structures are mapped to one dimensional models. This will inevitably result in errors, since thermal connections between different components inside one housing or on one heatsink are dependent on [...]

## Factors Influencing Thermal Resistance of Power Modules

Posted on 28 December 2020

This article describes various influences on the thermal resistance of power semiconductor devices. For an overview of heat transfer mechanisms, refer to the article "Heat Transfer in Power Semiconductor Devices".     Number of heat sources The number of heat sources spread across the heatsink has a crucial impact on Rth(s-a). Unless explicitly [...]

## Heat Dissipation and Thermal Resistance in Power Modules

Posted on 26 December 2020

In order to utilize the theoretical current capability as much as possible, power losses have to be optimally conducted through the connection layers - and for modules also through the insulation layers - to the heat sink. The quality of dissipation for the heat losses Ptot generated during [...]

## Integration of Peripheral Functions in Power Modules

Posted on 12 December 2020

A few examples of the integration of peripheral functions in power modules are described below. These are arranged in order of degree of integration.         Modules with integrated current measurement Firstly, current measurements in modules are taken to protect the power semiconductors from overcurrent, and secondly, the current signal is [...]

## Power Electronics Packaging Revolution

Posted on 20 July 2020

Power module packaging is driven by the ever increasing demand for higher power densities, reliability improvements and further cost reductions. The known reliability limitations of traditional solder joints and bond wires are holding back significant power density increases made possible thanks to higher junction temperatures and the future utilization of wide bandgap devices. Today, [...]

## Successful Selection of Power Modules

Posted on 20 June 2020

Successful selection of power modules for specific applications in every stationary and short-time operating condition depends on three factors. The first main factor is the voltage carrying capability. Second is the current carrying capacity of transistors and freewheeling diodes under the feasible cooling conditions and in conjunction with [...]

## Criteria for Successful Selection of IGBT and MOSFET Modules

Posted on 15 April 2020

Below are several important criteria that should be considered when selecting IGBT and MOSFET modules. 1.) Operating voltage Blocking voltage Since most power modules are used in DC voltage links which are AC-voltage supplied via single-phase or three-phase rectifier bridges, the blocking voltages of IGBT and MOSFET modules are adjusted to common line voltage [...]