why not use SC integrator in PLL design?

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qslazio

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Simple passive RC filter has been used for pll LPF design for many years,which suffering mismatch and large area problems.
Why we can not use Switched cap filter for loop filter?
What's the advantage and disadvantage?
 

the pulse generated by pfd is very small. So the charge will not transfer at the small time.

The continue filter for better jitter(small noise)
 

RC filter:

advantage: low jitter
dis-advantage: process, temperature dependent. BW controll is difficult

SC filter:
advantage: process, and temperature independen. BW controll is easier.

dis-advantage: higher jitter due to chage injection issue.

Yibin
 

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