3D PCB Converter Technology

Abstract:
The development of 3D converters implementing integration and advanced packaging of power electronics using printed circuit board (PCB) technology is presented. This to show how power electronics can benefit from the same advantages that have been exploited by the microelectronic industry, for some time already, regarding high density packaging, as implemented in modern digital photo and video cameras for example. Complementary technologies, enhancing the role of the printed circuit board from mere electrical interconnect medium to means to perform electromagnetic integration of passives, using specialised laminate material; to perform volumetric optimisation, using flexible foil; and to perform thermal management, using existing material and volume; are investigated. The development is performed in two distinctive technology stages to get to grips with the introduced advances in a modular way and shows promising possibility for increasing power density and enhancing thermal management capability of power converters in the power range of a few tens of watts. A first step sees geometrical optimisation from the original 2D component layout to 3D component layout by using flexible PCB technology. The second step is to include electromagnetic integration of passives to the 3D component layout by using rigid-flex PCB technology. Means towards thermal management enhancement is investigated in both these development stages. Quantitative evaluation methods are applied to compare the improvement in PCB technology along the way. Technological demonstrators along all the development stages illustrate the concept and have been subdued to undergo critical evaluation to determine the feasibility of 3D PCB converters in the future of power electronics.