This question makes me wonder if there're any designers left who still separate logic ground from the chassis ground in high-speed digital circuit design -and on what basis? I thought this whole issue of chassis vs. logic ground was something of the past. Regards, Ihsan On 8/14/06, chen_jinhua@xxxxxxx <chen_jinhua@xxxxxxx> wrote: > > Hi, > > I have a few general questions about the high speed cable grounding > scheme. It could impact both SI and EMI. I would like to have your > inputs about this issue. > > Scheme 1: cable does not separate logic ground and chassis ground. But > when it connects the system/boards, the system/boards have separate > logic ground and chassis ground. How do you separate/connect the logic > ground to chassis ground in boards? What is the pros and cons for SI > and/or EMI?=20 > > Scheme 2: Cable keeps separate logic ground and chassis ground. > System/boards also keep the separate logic and chassis ground. Cable > logic ground and board logic ground connects, and chassis connects the > chassis ground. How do you separate/connect the logic ground to chassis > ground in boards? What is the pros and cons for SI and/or EMI? > > Do you prefer scheme 1 or scheme 2? What is the pros and cons of scheme > 1 vs. scheme 2 for SI and/or EMI? Does SI and EMI have conflict > requirements? > > Thanks! > > Jinhua Chen > SI of Hardware Engineering > EMC Corp. > ------------------------------------------------------------------ > 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