Hello,
I am using an evaluation module of the LMX2581 to generate a 2.7GHz output with the minimum possible RMS Jitter. Using CodeLoader, I have programmed LMX2581 to Integer Mode to generate an RFout of 2.7GHz by providing a 100MHz square wave as an external OSCin . The Agilent E5052B Signal Source Analyzer is being to observe the noise performance of the generated output.
In the above scenario, the signal source analyzer shows an RMS jitter of 276.78fsec, when integrated from an offset of 10kHz to 10MHz.
However, when using the Clock Design Tool with the same Integer Mode settings and same loop filter values as that of the LMX2581EVM the simulation results show a much better RMS jitter of 120fsec for the same offset range.
What could be the reason for this large difference in simulated and experimental results? What can I do to improve the experimental results? Any help would be much appreciated.
Thanks and Regards,
Ajay