> The thought had crossed my mind but this needs to be as 'cheap as [potato] > chips'. (<$1) A processor is still an option at about that price level. You can consider doing digital temperature compensation with the processor. One suggested method is to use the watchdog timer variations wrt crystal as a measure of temperature and compensate accordingly. RM -- http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu