Dear All,

I have questions about period jitter

As far as I know, there are two formulas for obtaining period jitter.
I've attached a image to make it easier to see the formula below.

1. sqrt(2*L(Δf)*(Δf)^2/fc^3)

2. (T/2pi)*sqrt( integ(4sin(pi*T*f)^2 *(2*L(f)))df )

Does anyone happen to know what the difference is between the two
and what expressions should be used in a normal PLL

Best regards,
Sangjin