Distributed parallel connected semiconductor devices spaced for improved thermaldistribution and having reduced power dissipation

摘要

A single triac on a heat sink is replaced by a plurality of lower rated current, parallel connected triacs for carrying the same total current as the single triac. The plural devices are spaced apart as far as possible, within the confines of an insulation back cover, to reduce the thermal gradient across the heat sink and to reduce the input thermal power to the heat sink. Thermally conductive compressive sheets thermally couple the flat heat sink to a face plate on the side of the heat sink opposite to the side receiving the triacs.