demand for power modules providing higher currents. The conventional approach to fulfill this requirement is to look for dedicated, high-current power modules. This article describes the alternative approach of paralleling IGBTs and diodes within one power module to extend its power capability, for example, by using a 35A sixpack module as a 100A half bridge.
This approach provides an advantage due to the improved thermal behavior of several small chips rather than fewer big ones. The breakthrough in performance is seen when real-life data of parameter variations within one power module are considered, instead of the datasheet values, which suggest a much higher spread than actually seen in real life.
Special care has to be taken regarding the drive circuit, and current derating must be considered when calculating the current of a single chip used in a multi-chip arrangement.
Individual emitter sense, down to chip level, and symmetrical design, are required of the power module. And with the use of components in parallel, not only can higher current levels be reached, but also the reliability of the design can be improved.
For the complete article, which looks threshold voltage and switching behavior, circuit symmetry, on-state behavior, and thermal runaway prevention, click here, courtesy of Automotive Designline Europe.
Receive a weekly highlights update delivered directly to your inbox by signing up for our weekly automotive electronics newsletter here