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SPICE Circuit Parameter Extraction

  1. Aug 14, 2012 #1

    I am looking for information on how to extract circuit parameters.

    I have a system, and I can experimentally perform current and voltage measurements. For example, I can measure the voltage response of the system as a function of a given input pulse.

    In addition, I also have an equivalent circuit model to represent this system, composed of various resistors and capacitors.

    What I don't know is the resistance and capacitance values for the elements in my equivalent circuit model.

    I was wondering if there are tools, like SPICE tools, or methods to extract the circuit parameters that would fit the best my experimental data. I have a SPICE extraction tool, however it is designed to extract transistor parameters. I can't find tools that can extract general circuit parameters. I am not sure that I am being very clear, so please let me know if this is confusing, and if you have suggestions on tools and methods.

    Thanks a lot!
  2. jcsd
  3. Aug 14, 2012 #2
    If your circuit is all passive, you can get equivalent circuit components by measuring resistance and inductance/capacitance.
  4. Aug 19, 2012 #3

    Thanks for your answer. My system is a black box, so I can't just go and measure the resistances and capacitances. I have an equivalent circuit model for my system, and I can obtain experimental data from the system, so I am just looking for a tool that will fit the equivalent circuit model to the experimental data.
  5. Aug 20, 2012 #4
    If you have experimental data, then you can use Matlab/Origin etc. to curve fit on the data using a custom defined curve. If you want to fit it in SPICE model the work is same. However, you have to know the SPICE model equations which will be used for fitting.
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