rjiang
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Hi, I want to estimate total noise (thermal,1/f) of a switched-C circuit. The circuit is pretty big and has correlated-double sampling to reduce 1/f noise.
I started pnoise analysis on a very simple circuit. It has only one NMOS switch and a 1pF cap. clock is 10MHz. I ran pnoise analysis and integrated the total noise. The result is much higher than KT/C (c=1pF).
I have following questions: [1] Is pnoise the right way to estimate switched-C circuit noise? [2] the noise floor is much higher than 4KTR. In pnoise analysis, "noise type" is time domain. If noise type is source, noise floor looks OK. But I do not know the exact time for this analysis. [3] output noise should be periodic every 10MHz. But it is like a continuous-time spectrum without repeating or aliasing. [4] If correlated double sampling is used, can pnoise take this into account?
thanks,
R.J.
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