2 Replies Latest reply on Jun 25, 2012 11:25 AM by DaKn_263916

    Error n connecting resistor

      I am facing the problem in connecting the resistor  to the circuit ...i send the pic of the circuit and the error too...plz provide some information in how avoid that error.....

        • 1. Re: Error n connecting resistor

          Since your resistors are external parts (as all annotation components are) you have to connect them via pins to the outer world.





          • 2. Re: Error n connecting resistor

            Are you trying to build a simple OpAmp summer ? If you don't need


            the hi Z afforded by the PGAs you can always eliminate them. And


            take your gain individulally for each channel by picking specific input


            resistors. Also offset the OpAmp so circuit works with - values.








            Right now your circuit has a gain of - 1 in the OpAmp summer, referenced to ground,


            hence will not work, eg. output of OpAmp cannot swing below ground w/o you offsetting


            the NI input from something higher than Vss.




            Note dropping PGAs has the additional advantage of less offset and drift. If


            you still need super high Z inputs, have to use PGA, you still have to offset the






            Regards, Dana.