Adding Conducted Emissions Limit Lines

Is it possible to add Conducted Emissions Limit Lines directly into the FFT?
I already tried to add them as CSV data but the plot window draws only the first horizontal segment.


FFT is a complex number (same as .ac). In Qspice, complex number is expressed as Re,Im format. For example, to specify a point, it should be written as X,Y for X+jY.

Here is an example for your reference. Just beware that

  1. The dot are connected with a straight line in linear scale, therefore, it is curved in log scale.
  2. If you change .csv file, and drag and drop into waveform viewer, you must first remove the previous overlay .csv from File > Overlap Simulations. Or you will not see the curve get update.

Thanks for the reply. Just removing the .csv was not enough. I have to recalculate the FFT at least.

I hacked my way around it and wrote a little Python script that accepts the limit values and does a reverse log interpolation to get straight lines in between. Not the most elegant solution, but it works.
CalcConductedEmissionsLimitLines.py (1.7 KB)

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