Jim, I would try to avoid using this plane as a reference plane due to return-path discontinuities, which occur due to switching of the reference plane at several points along the signal path. Such discontinuities result in increased inductance at low frequencies and power plane bounce at high frequencies. An adjacent signal line is affected from this plane independent of whether it is floating or tied to other planes. If you have a stripline configuration, there are two reference planes, and the return current is distributed on the planes inversely proportional to their distances from the signal trace. Ege "Peterson, James F (FL51)" schrieb: > > Greetings, > > If we have a copper plane that is used for thermal relief and is not tied > directly to digital ground, can it be used as a reference plane? Note : This > thermal plane is tied to the chassis which has a single point connection to > digital ground (located on the backplane). > > Will an adjacent signal layer see this as a reference plane? > > thanks, and regards, > Jim Peterson > Honeywell > > ------------------------------------------------------------------ > 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 > -- Binary/unsupported file stripped by Ecartis -- -- Type: text/x-vcard -- File: engin.vcf -- Desc: Visitenkarte für Ege Engin ------------------------------------------------------------------ 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