Study on the Switching Time-Variation of Simultaneously Controlled IGBT: Case of Defibrillators Design

Samples of integrated gain bipolar transistors (IGBT) of the same type but produced under different technologies were tested about the switching time-variation. This is of high importance when several IGBT are connected in series to commutate high voltage defibrillation shocks. Very often, a short voltage overload of one of the IGBT in group leads to electrical breakdown of all transistors, due to nonsynchronised driving of the gate-emitter circuits. The goal of the study was to check whether compensation of the delays introduced throughout the IGBT control circuits might be efficient despite the own dispersion of the transistor parameters.