My probes reach out to measure the voltage across drain and source of the NFET, and reality pauses while the result is obtained ... .... would be a good check of the math. --=20 James Cameron http://quozl.linux.org.au/ --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .