manuelsu
Newbie level 4
I am developing a distribution path for a 100MHz clock. When the phase noise is simulated, the results show a large spur at the frequency of 100MHz. The integration of the noise power density spectrum neglecting the spur provides a jitter smaller than 1ps while the spur provides a jitter over 1ns. The top value of the spur compared with the noise at 1Hz stay constant independently of the cell simulated: buffers, inverters… There is some explanation for the spur?
Simulation parameters:
. Input: Square signal
· Toot: cadence spectre
· Beat Freq:100MHz
· Num Harmonics: 60
· Points per Dec: 80
· Sweeptype:absolute
· Noise type: jitter/Sources
Of course i can filter the peak with less than 20 points/dec i need understand what and how to deal with it.
Thank you in advance.
Best regards,
M
Simulation parameters:
. Input: Square signal
· Toot: cadence spectre
· Beat Freq:100MHz
· Num Harmonics: 60
· Points per Dec: 80
· Sweeptype:absolute
· Noise type: jitter/Sources
Of course i can filter the peak with less than 20 points/dec i need understand what and how to deal with it.
Thank you in advance.
Best regards,
M