Eye diagram function

This doesn't make any sense, for several reasons:

1. pnoise produces frequency domain results - you see the output noise power spectral density versus frequency.
2. An eye diagram is a time domain metric - you need time domain waveforms coming into the function - so phaseNoise is completely inappropriate.
3. Even assuming that you'd run (say) transient noise instead to get a noisy time domain waveform, using the eyeDiagram function doesn't make sense, because it relies on having a fixed clock frequency, which is unlikely to be the case with a VCO.
4. More likely to be useful with a time domain VCO waveform is to run time domain noise, and then use the freq function to get the instantaneous frequency, and then plot a histogram of that (exactly how depends on whether you're using IC5141 or IC61).
5. But to be honest, pnoise will be more efficient. Perhaps you can use the "jitter" mode if you want to get some idea of jitter metrics - not really sure what  your goal is.

Regards,

Andrew.

Hello Andrew,

I got it now, I was using eye diagram function in wrong context.

So, what is the use of eye diagram function or rather how should I use this function to calculate frequency in an LC VCO circuit?

Oh and I am using spectre ICI5141.

Regards

You'd probably be better off using the "freq" function in the calculator instead, from a transient run, to plot instantaneous frequency versus time for the VCO. Or use the harmonicFreq function to get the frequency from the PSS results (easiest way to do this is to use the Results->Direct Plot->Main form, check the "Add to Outputs" checkbox, and then pick the "frequency" choice (I think that's what it is) and choose harmonic 1, say; this will add the right expression into your ADE Outputs Pane).

Regards,

Andrew.

 Hello Andrew,

I GOT IT :)

Now, how do I calculate the phase noise?

Thanks & regards,

starsky