Hi all, We are layout one 3.0Gbps high speed backplane. The original design style is routing the edge coupling differential signals in the internal layer, with adjacent GND plane. Now we met the layer limitation, and here is the questions, 1. Can we routing the differential pair on the top layer with GND plane on the second layer? In my knowledge, it seems functional but odd. Please give your advice. 2. Can we use one continuous power plane (12v or 5v) as the reference plane to the high speed signals? For example, if 3.0Gbps signals on top layer works, can the second layer be +12v power plane? Thanks in advance, Best Regards, George USI Shanghai RD Center ------------------------------------------------------------------ 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