A novel integrated packaging technique for high density DC-DC converters providing enhanced efficiency and thermal management

As current requirements of microprocessors and ASIC´s increase, traditional packaging techniques limit the electrical and thermal performance of DC-DC converters designed to supply these low voltage, high current loads. This paper describes a novel integrated packaging technique that uses a copper lead-frame in the high current path to reduce the electrical and thermal resistance of the DC-DC converter. The lead-frame is used to integrate the single turn secondary windings of the power transformer and the output choke. This integrated structure also serves as the high current interconnect to the motherboard, and a heat-sink for the secondary synchronous rectifiers. A 1.8 V 100 A industry standard half brick is used to demonstrate the performance advantages of the new technique.