Thanks Michael, Olin Most of the larger diodes I have from disassemblies are TO220 Schottkys, which I often re-use in SMPS or for steering. AIUI they're not suitable for bridges because of their poorer reverse characteristics. Just checking that fast/ultrafast didn't have any limitations I wasn't aware of and have more in common with standard silicon rectifiers Joe --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .