>I haven't used any in a medical design yet (although I will be later >this summer) and that will probably be revealing as they will get >zapped with up to 18KV for ESD testing. This is where the E version of the maxim parts may help you - rated for quite high ESD pulses. They are applying the E rating to a fair number of the interface chips these days. -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist