Frank99
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hi,
I am running simulations on a crystal oscaillator to verify the period jitter using a few different approach.
A. running pss and pnoise td gives Jc[1k] rms=50fs, peak2peak_BER=10e-3]=300fs B. running long transient simulation and using the built-in period_jitter function gives 300fs C. using the same transient data and plot eye diagram. use crosshair to measure the width of the rising(or falling) edge gives 30fs.
i initially thought result from A and B and C should all agree but now i have doubt.
question 1. result A and B matched, but I was told pss/pnoise uses device noise where as transient (default) does not have device noise in the model. is this true? if so how do i get the device noise into a transient simulation?
2. B and C uses the same data, and i expected the result to match. Any idea as to why?
3. is there any other way to verify the period jitter again pss/pnoise other then transient
4. (unrelated) in the noise summary, the strobe noise sim provides noise at a particular threshold. however in the noise summary from a pnoise type=source, it only provide a single number. user guide says this noise summary is an average noise over the cycle. any idea on what the formula is?
thank you very much for your help.
Frank
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