Hi,
1) I simulated the phase noise of LC VCO at 5GHz in cadence and integrated from fl=10Hz to fh= 2.5GHz to get jitter as follows
Jc=1/(2*pi*fc)sqrt(2*integ(10^PN/10) from fl to fh)

I find it to be 960ps!!
I tried to compare with time average Jc and interated from fl=10Hz to fh=2.5GHz using cadence direct plot and I can see only 6.7f

How do I get it from phase noise skirt?

2) Also, since phase noise theoretically is boundless and becomes infinite at 0Hz, intgerating it will also give boundless value. Is it equivalent to saying that accumulation jitter is also boundless?