On Tue, Mar 8, 2011 at 11:19 AM, Olin Lathrop wr= ote: > N. T. wrote: > > Yes. You can use LTC2053 instead of LT1168. > > LTC2053: > > CMRR is typically 116dB. > > Average Input Offset Current s typically 1nA. > > > > LT1168 > > CMRR 90dB Min > > How is that supposed to help with a DC bias voltage problem? What he nee= ds > it high pass filtering, which has nothing to do with the common mode > rejection ratio of the instrumentation amp. He was most likely addressing the issue of a 60Hz signal going through the heart signal. I posted about it a little while ago. Perhaps he posted in th= e wrong thread? --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .