tumeda
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I wanna get the jitter specification of the whole PLL circuit based on these Veriloga Models of Ken's Paper. To simplify, we assume the Jitter comes mainly from two block VCO and PFD/CP. The following questions are still not very clear for me! thanks a lot for your hints! 1. From the matlab code in list 17, the jitter can be got from "J=std(periods)". Since the periods come from the VCO output, which are generated by the code "$abstime-prev" in List16. So I think the J is cycle-to-cycle Jitter. Is it right? 2. For the VCO block, the Jvco can be calculated by "Kvco=sqrt(c*T)". The Jvco is cycle-to-cycle Jitter, because there is no edge-to-edge jitter in VCO. So I can directly set the Jvco as the VCO period jitter value in the List 16. Is it right? 3. For the PFD/CP block, the Jee can be calculated by the formular57(Page28 ). But this Jee is edge-to-edge jitter, could I directly set the Jee as the synchronous jitter of PFD/CP in List10? or use the Jcc=sqrt(2)*Jee ???
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