Repetitive avalanche of automotive MOSFETs

This paper will focus on one of the most difficult operation modes of automotive MOSFETs, the operation in avalanche in particular repetitive avalanche. Whereas single pulse avalanche conditions are typically very well defined and tested, repetitive avalanche operation is always an area of discussion as the number of influencing parameters is considerably higher. In automotive applications a vast range of requirements for repetitive avalanche are visible: starting from applications with only a very limited number of avalanche cycles however with comparably high energy, via applications which use the MOSFET avalanche capability on purpose to turn off inductive loads, towards applications switching the MOSFETs billions of times with very low avalanche energies. In this paper we discuss the requirements of repetitive Avalanche from application point of view, give some basic information on avalanche mode and test results of single and repetitive avalanche explained and assessed. Failure modes will be highlighted.