Donovan Parks wrote: > How about measuring the voltage drop across the HEXFET in the H-bridge? Is > Rds(on) fairly stable, or does it fluxuate widely with increase temperature? > (I don't have a HEXFET to test with). You can get special hexfets that bring one "cell" out to a separate lead, providing a sample of 1/100 or 1/1000 of the total load current. A sense resistor between this lead and the corresponding "main" terminal has a much more reasonable value. -- Dave Tweed -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.