What kind of supply noise should be applied on PLL supply for phase noise measurement

[sainiparvesh]

Hi,
If the bandwidth of PLL is e.g. 1MHz then what kind of noise should be applied in its spice simulations to measure the supply noise impact on PLL phase noise performance?

 

[crutschow]

Do you have a specific type of power supply in mind?

 

[sainiparvesh]

To quote the jitter of PLL, what kind of noise I should apply in simulations. e.g. If the bandwidth of PLL is 1MHz, should I apply noise like 100mv pk-pk sinewave of frequencu 100kHz or 1MHz or 10MHz or I should quote PLL phase noise number on these various frequencies. In general noise whatever comes to the PLL is not known, so my question is what kind of noise people apply to quote the jitter number, Is there any rule of thumb, which says If PLL BW and o/p frequency is given then this much type of noise should be injected on PLL supply to get the realistic phase jitter numbers in spice simulations.