uc3902app report.pdf

Application Report SLUA128A - May 1997 – Revised January 2003 The UC3902 Load Share Controller and Its Performance in Distributed Power Systems Laszlo Balogh System Power ABSTRACT Users of distributed power systems are seeking reliable and economic solutions to supply their loads. A modular approach, where stand alone power supplies are utilized for local power conversion, is widely accepted in these applications. The power rating of the individual converters are usually limited by the available height, board space and by the limitation on volumetric heat dissipation. High current loads are supplied by several parallel connected power supplies. In addition to higher currents, the parallel modules can also offer redundancy, an important factor to achieve reliable, uninterrupted operation and extended life expectancy in these systems. Contents 1 UC3902 Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 2 UC3902 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 3 UC3902 Load Share Controller Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 4 Design Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .