Antonio Sergio Sena wrote: > The filtering i have is a couple of electro caps. If i add some ceramic > (eg 100nF), the SMPS doesnt start. That's not good. This probably means your switcher is right on the edge at startup, and is relying on the ESR of the electrolytic caps. Ugh. ***************************************************************** Embed Inc, embedded system specialists in Littleton Massachusetts (978) 742-9014, http://www.embedinc.com -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist