Stephen R Phillips wrote: > I'm looking into designing a high power SMPS > The design critera is a bit interesting. > 1) Active Power factor correction <-- doable > 2) > a) 60V 10A peek > b) 2-48V 5A peek supplies > c) peek indicates this is the max current that is to be drawn but not > neccesarily for more than 2 minutes. > 3) it is not for telecom use > 4) wide supply range 120VAC - 240VAC > 5) High efficiency, I prefer > 80% goal is actually 90% or better Definitely doable, but at these power levels, I would tend to go for a multi-phase implementation for both the PFC and the buck converters, to help keep the ripple currents and EMC issues manageable. I assume that you mean two outputs of 48V/5A each, not a single adjustable 2 to 48 volt output. 2 minutes is a long time, and so your specs must be considered as steady-state requirements. Surge current specifications are usually for 10 seconds or less. > Anyhow has anyone had success with > 500W supplies that won't go > nuclear if loaded heavily on ocassion? The key is having enough control so that the inductors never saturate. Olin will probably have additional suggestions... I was wondering whether you had looked at commercial products like Lambda and Vicor, but I see that they don't really have much in the way of standard products that go up to 60V output. -- Dave Tweed -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist