Hi Team,
My customer is evaluating LMX2572 on their ES board. They saw difference of sub-fractional spurs of LMX2572 between the 1st ES board and the 2nd ES board under the same application of LMX2572 and settings.
They understand the solution that they can set the fractional DEN to an irrational number such as 400001234 to eliminate those spurs. But they do not do that, because small spurs will increase, although the level of sub-fractional spurs becomes lower.
They want to know how much the sub-fractional spurs, 1MHz and 500kHz spurs of 5523MHz setting, or 250kHz and 125kHz spurs of 5629.25MHz setting, vary by variation of LMX2572 characteristic, part to part, or lot to lot.
Are there any reference data for that?
Thank you.
Best Regards,
Koshi Ninomiya
