Raj, sorry it took time to get back to you, but I think both Scott and=20 Istvan have answered your question anyway. Your best bet with DDR is to=20 keep the bus as short as practical. You mentioned unterminated. You had=20 best simulate the heck out of that, as unterminated DDR can be very=20 problematic. Regards, Steve At 07:51 AM 4/27/2004 -0700, raj singh wrote: >Steve, sorry for such a 'to the point' question. > I should have been more descriptive.... >I have a DDR data driver to be used in point-to-point >source terminated(unterminated) enviorment. I am using >spice simulation to find out for what T-line delay >driver gives worst jitter, rest all are fixed (PRBS, >pkg parasitics, clk freq, Z0=3D50 ...etc). I am >simulating just one driver. > I found that it is not Td=3Dlambda,lambda/2,lambda/4 >which gives worst jitter, but values slightly less >than this. WHY THIS? is what I want to clarify. > >Thanks >Rjt > >--- raj singh <forsilist@xxxxxxxxx> wrote: > > Hi all, > > > > What t-line delay (in terms clock period) will show > > the worst driver jitter. Some papers, which i have > > gone through, says it is when Td equals clock > > period, > > half the clock period or quarter the clock period > > (calls it resonant frequency). > > But cannot able to think of why is it so? Tried to > > devolope some of my own ideas, but want to discuss > > with the list to get correct answer. > > > > Thanks and regards, > > Rjt > > > > > > > > > > > > > > __________________________________ > > Do you Yahoo!? > > Yahoo! Photos: High-quality 4x6 digital prints for > > 25=A2 > > http://photos.yahoo.com/ph/print_splash > > >------------------------------------------------------------------ > > 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 FAQ wiki page is located at: > > > > http://si-list.org/wiki/wiki.pl?Si-List_FAQ > > > > List technical documents are available at: > > http://www.si-list.org > > > > List archives are viewable at: > > //www.freelists.org/archives/si-list > > or at our remote archives: > > http://groups.yahoo.com/group/si-list/messages > > Old (prior to June 6, 2001) list archives are > > viewable at: > > http://www.qsl.net/wb6tpu > > > > > > > > > >__________________________________ >Do you Yahoo!? >Win a $20,000 Career Makeover at Yahoo! HotJobs >http://hotjobs.sweepstakes.yahoo.com/careermakeover >------------------------------------------------------------------ >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 FAQ wiki page is located at: > http://si-list.org/wiki/wiki.pl?Si-List_FAQ > >List technical documents are available at: > http://www.si-list.org > >List archives are viewable at: > //www.freelists.org/archives/si-list >or at our remote archives: > http://groups.yahoo.com/group/si-list/messages >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 FAQ wiki page is located at: http://si-list.org/wiki/wiki.pl?Si-List_FAQ List technical documents are available at: http://www.si-list.org List archives are viewable at: //www.freelists.org/archives/si-list or at our remote archives: http://groups.yahoo.com/group/si-list/messages Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu