An Alternative Approach to Parasitic Turn On Detection

Inhalt:
In this paper we consider a power module, built out of several chips in parallel at each of the switch positions. We investigate potential causes of unwanted parasitic turn on (PTO) which may occur as a result of a switching event in the complementary position in a half-bridge. By extending the use of the classical double pulse setup, we develop a method and an associated quantitative metric to assist the user of the module (in any application condition), to (a) determine if the module suffers from PTO and (b) set driving methods to robustly avoid PTO across the life of the module. The method is particularly relevant for the new class of fast switching wide band gap, e.g. silicon carbide (SiC) based power modules.