4 Replies Latest reply on Nov 24, 2017 8:25 AM by user_342122993

    Problems with adc and differential opamp

    joona.rintamaki_2867716

      I'm using CY8CKIT 049-42xx and I'm trying to measure muscle impulses with surface electrodes. I have managed to get some kind of signal, but it is working inconsistently and dc level of the adc is different from run to run. Sometimes I can see a clear signal, sometimes nothing at all.

       

      When it works, the dc of the signal is around 0 and signal jumps around 10-20mV, when it works badly it jumps between 50mv and 0 and it's hard to get anything cohesive out, sometimes spiking to 1024 (possibly due to bad usb connection).

       

      I am wondering if there are flaws in my design or the way I'm using the device or is this due to bad connection and noise? I have attached the project folder. The registers show in top design aren't currently used for anything, they're just placeholder for future.

       

      Br

       

      Joona R