Steve. You are right, I saw that Noise and Jitter on output of IO gets minimized when I see the output of IO w.r.t same noisy reference vss. But it only gets minimized but not completely gone. Is it because of the finite routing delays of vddio,vss and signal within the IO and also signal delay is not the same as the supply delays. Is my understanding correct. Naresh -----Original Message----- From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx] On Behalf Of steve weir Sent: Wednesday, October 08, 2014 12:45 AM To: si-list@xxxxxxxxxxxxx Subject: [SI-LIST] Re: Single ended Noise OR Differential Noise All voltage noise between a single-ended transmitter and receiver causes jitter. Single ended jitter is minimized by: Launching against a single reference, propagating the transmit energy against that same reference, and tightly coupling the receiver threshold voltage to that same reference. Steve. On 10/7/2014 6:10 AM, Naresh Dhamija wrote: > Hi folks, > > I am doing power noise analysis on a system that uses SSTL IO buffers. > I am seeing the ripple on the IO output signal - such that during hi > state IO output signal follows the noise whatever is on the vddio and > during low state, IO output signal follows the noise on the vss. > Observing this phenomenon, I purposely forced IN PHASE single ended > noise to both vdddio and vss of almost the same frequency as of data > rate but uncorrelated with data rate. Since noise forced to vddio and > vss are IN PHASE so Differential Noise measured between vddio and vss > at each instant shows zero noise. But still I see jitter on the edges > because of finite rise and fall times, the initial low level and final > high level for a transition from low to hi are not always same. Does > this mean that along with differential noise, single ended noise on > power and ground also cause jitter to IO driver. > > Regards > Naresh > ------------------------------------------------------------------ > To unsubscribe from si-list: > si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field > > or to administer your membership from a web page, go to: > //www.freelists.org/webpage/si-list > > For help: > si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field > > > List forum is accessible at: > http://tech.groups.yahoo.com/group/si-list > > List archives are viewable at: > //www.freelists.org/archives/si-list > > Old (prior to June 6, 2001) list archives are viewable at: > http://www.qsl.net/wb6tpu > > > -- Steve Weir IPBLOX, LLC 1580 Grand Point Way MS 34689 Reno, NV 89523-9998 www.ipblox.com (775) 299-4236 Business (866) 675-4630 Toll-free (707) 780-1951 Fax All contents Copyright (c)2013 IPBLOX, LLC. All Rights Reserved. This e-mail may contain confidential material. If you are not the intended recipient, please destroy all records and notify the sender. ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: //www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List forum is accessible at: http://tech.groups.yahoo.com/group/si-list List archives are viewable at: //www.freelists.org/archives/si-list Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: //www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List forum is accessible at: http://tech.groups.yahoo.com/group/si-list List archives are viewable at: //www.freelists.org/archives/si-list Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu