1 Reply Latest reply on Sep 21, 2017 6:47 AM by vsrs

    Multi Channel Polarised Resistance Measurement

    andre_2566351

      I am trying to implement a polarised resistance measurement using a PSoC4245 (CY8CKIT-049-4200)

      I have successfully implemented a single channel measurement implementation.

      I use an IDAC as current source, and a ADC to measure the voltage the IDAC outputs.

      I am using an differential AMUX, where I connect one input to a pin, which is connected to ground. I haven't found a programmable analog ground source, therefore using an external pin to ground. The other input of the AMUX goes to the IDAC/ADC combination, and the output go to pins where I wish to measure.
      (Design02.cydsn)

       

      So far, this works fine. However, when I try to configure multiple channels, it fails,

      I have tried to select the channel first, then the polarity, then the "Generate Application" function optimises out the channel selection, therefore making it impossible to select a channel.

      Info: pft.M0106: AMux component (AMux_Sel) has been optimized out of the design and will not do anything.

      (Design02_SEL_POL.cydsn)

       

      I have tried to select the polarity first, then the channel, then it fails to generate the application, complaining about it is not possible to hook up the muxes like this.

      Net "Net_180" is connected to analog mux "AMux_Channel_CYAMUXSIDE_A" and analog mux "AMux_Polarisation_CYAMUXSIDE_A", but it may connect to only one analog mux when it is an analog mux common connection

      (Design02_POL_SEL.cydsn)

       

      • My questions:
        Is it possible to implement something like a multi channel polarised resistance measurement using this PSoC, or any other?
        Is it possible to reach an analogue ground without the need to connect it to an external pin?