pll vco control voltage issue

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sonnyasu

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vco control

hi I'm having a problem here with my control voltage to vco. after the loop filter, the control voltage looks like the plot in the attachment. Anyone knows what the problem is?
 

pll vco

What are you showing, an oscillosope trace, or some sort of simulation? What part do you not like about the trace?
 

It's from the simulation. I think the spurs is not supposed to appear like that. Any idea?
 

the spur comes from the mismatch in your charge pump

4mV is not a big deal !
 

Here is another screen shot of slow corner with cold temperature. The control voltage is on the top. Does this look normal? I thought the vco is out of range at the beginning but when I double check the vco frequency, it is in the range.

Added after 52 seconds:

here is the image
 

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