On Wed, Jan 26, 2011 at 12:46 PM, V G wrote: > On Wed, Jan 26, 2011 at 1:38 PM, Michael Watterson wro= te: > >> =A0OR ICL7660 >> maybe. >> >> I have also used the RS232 interface chip to get + and - 9V supply from = 5V > > > Good idea. But for now, I'll stick with the batteries. Less that can go > wrong. You could use a low-voltage part, like INA333. If I remember corrctly, the datasheet has some electrocardiograph examples. Regards, Mark markrages@gmail --=20 Mark Rages, Engineer Midwest Telecine LLC markrages@midwesttelecine.com --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .