sheldon
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Visjnoe,
There are some aproaches for including noise effects in the simulation:
1) Create a clock source with random jitter. This will allow you to capture the sensitivity of the design to aperature jitter or noisy clocks.
2) Also Spectre now supports large signal transient noise analysis which would allow you to see the effect transistor noise on the overall performance of the design.
Also it may be easier to perform this analysis on the just the Sample and Hold block rather than trying to simulate the entire ADC. First it is easier[runs faster] and for most designs the S/H limits the performance anyway. This is important because you need to set the simulator settings conservatively for large signal noise analysis. Also, as Anurag pointed out the noise floor of an ADC is limited by quantatization noise, however, the noise floor of the S/H is limited by "real" noise. So it is easier to analyze the circuits performance.
Finally, my experience is that this problem is a good application for behavioral modeling. You really don't need all the information that transistor level simulation provide and you do need a lot of speed. Also the ability to on and off noise sources is really useful for understanding and eliminating noise issues.
Best Regards,
Art Schaldenbrand
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