Rise time and dwell time impact on Triac solder joints lifetime during power cycling

In this paper, we analyze the rise time and dwell time impact on 16A-600V high temperature Triacs reliability subjected to power cycling. Experimental tests, performed on two TO-220 packages (insulated or not), show that rise time and dwell time have a negligible contribution on Triacs lifetime. Failure analysis confirms that the physical failure mode (the die-attach fatigue) and the failure location (the solder joints) are similar when rise and dwell durations change. Thermo-mechanical simulations (ANSYS^®) were performed to get a better understanding of the effects of various ramp and dwell values on solder joints plastic work and shear stress.