Hey Fabrizio, My personal opinion is that Node 0 is probably not your "ground" on your backplane OR on your card. At least not if you are trying to simulate the signal return paths accurately and not assuming perfect grounds. You have to be careful with Node 0 because it is often used inside spice subcircuits to help convergence issues. my $.02 jon -----Original Message----- From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx]On Behalf Of Fabrizio Zanella Sent: Thursday, February 27, 2003 4:52 AM To: si-list@xxxxxxxxxxxxx Subject: [SI-LIST] Ground nodes in spice I have a question regarding backplane simulations of serial 8b/10b signals, running 2.5Gbs and above. Does it matter whether the ground nodes of the daughtercards and backplane are all set to 'zero' or to a floating node for eye pattern results? Thanks, Fabrizio Zanella Principal Hardware Design Engineer Broadbus Technologies fzanella@xxxxxxxxxxxx =20 -------------------------------------------------------- =20 This email message and any files transmitted with it contain = confidential information intended only for the person(s) to whom this = email message is addressed. If you have received this email message in = error, please notify the sender immediately by telephone or email and = destroy the original message without making a copy. Thank you.=20 =20 ------------------------------------------------------------------ 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 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 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