8 Replies Latest reply on Jun 20, 2018 2:54 PM by user_119654

    Trying to configure the OpAmp for Mode:OpAmp and Mode:Follower at run-time

    user_119654

      Hi,

       

      I'm a seasoned PSoC application designer.  I'm using a PSoC 5LP.  I have an application that uses the OpAmp v1.90.

       

      Most of the time I need to configure the OpAmp with a mode = OpAmp.  The '-' input is routed to an external pin of a current sense resistor.  However due to the < 1Meg ohm input impedance (observed but not specified in the datasheet), I cannot resolve to < 30uA of current due to the extra draw and resultant noise.

       

      If I "hard" configure the mode = Follower, I can resolve very low currents to ~ 1uA with much lower noise.

       

      I want to configure the OpAmp to mode = OpAmp in the TopDesign and switch to mode=Follower in the code at run0time when needing to resolve to 1uA.  I can operate at the register level if needed but it would be nice if there were some API calls to provide this.

       

      Note:  I tried using a analog mux external to the OpAmp to perform this desired function.  I noticed many problems doing this successfully and had to abandon the attempt.

       

      Thanks for the help in advance.

       

      Len