Olin Lathrop wrote: > Doesn't it make sense that if something is really close to failing that a > error might not show up when at one limit condition but not the other? Not necessarily. Take a simple diode... they in almost all cases either fail at any point in their operating range, or not at all. It's a question about the exact failure mode and how it relates to voltage. Gerhard -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist