Thread Links Date Links
Thread Prev Thread Next Thread Index Date Prev Date Next Date Index

Re: [802.3_50G] 802.3cd: Jitter Question


Typically DC-DC convertor will have one dominant tone output like 3rd or 5th harmonic, etc.  Given today efficient DC-DC convertors operates at > 1MHz 
it is much easier to filter the spurs with reasonable size low-ESR capacitor, which was not the case when DC-DC convertors operated at 50 KHz!

Obviously >1 MHz DC-DC convertor can’t generate multiple of UIs into SerDes output and pass limits we already have in place!

Ali Ghiasi

On Jan 17, 2018, at 10:16 AM, Bill Kirkland <wkirkland@xxxxxxxxxxx> wrote:

The analysis was done analysing a single tone.
Is it possible to get a bad spur from tones from a switching power supply that could influence the behavior in the analysis?