Aging test results for high temperature TRIACs during power cycling

This paper deals with the functional reliability study of a new 16 A - 600 V high-temperature TRIAC family, subjected to power cycles, simulating the component in harsh real operation conditions. The targeted application is a vacuum cleaner (1800 W - 230 V - 50 Hz). In this kind of application, one of the major issues for TRIAC, which leads to high mechanical stresses for the assembly, occurs when the switch turns-on in ldquojammed nozzle operationrdquo, i.e. when the tube is blocked. In that case, the TRIAC junction temperature reaches at most 180degC, higher than the maximum value specified by the manufacturer (i.e. 150degC). The aim of this study is to evaluate the TRIACs lifetime under these operation conditions. The thermal stresses generate local temperature variations and then, some mechanical stresses (assembly degradation). For TRIACs, the junction-to-case thermal resistance (R
_th(j-c)
) increase is the signature of such a damage. The lifetime has been studied and fitted with a Lognormale distribution. The components damages, due to the mechanical stresses, have been explained thanks to some qualitative two-dimensional thermo-mechanical simulations using finite elements (ANSYS
^reg
).