Aubrey, I am trying to get a realistic estimate of the crosstalk on the databus, and my preliminary target is to limit the crosstalk to under 100 mV. When I change the Minimum Coupling Length from 200 mils to 50 mils, the reported crosstalk amplitude increases from 50 mV to 200 mV. This is the total crosstalk from all neighbors. Regards, Ravinder Server PCB Development Hitachi Global Storage Technologies Email: Ravinder.Ajmani@xxxxxxxxxxxxxx <Aubrey_Sparkman@xxxxxxxx> 12/29/2005 09:18 AM To <Ravinder.Ajmani@xxxxxxxxxxxxxx>, <si-list@xxxxxxxxxxxxx> cc Subject RE: [SI-LIST] Selection of Minimum Coupled Length in Cadence SPECCTRAQuest Ravinder, The Minimum Coupling Length isn't the only setting you can change that will affect the reported crosstalk. What is your goal? Aubrey Sparkman Enterprise Engineering Signal Integrity Team Dell, Inc. Aubrey_Sparkman@xxxxxxxx (512) 723-3592 -----Original Message----- From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx] On Behalf Of Ravinder.Ajmani@xxxxxxxxxxxxxx Sent: Wednesday, December 28, 2005 6:39 PM To: si-list@xxxxxxxxxxxxx Subject: [SI-LIST] Selection of Minimum Coupled Length in Cadence SPECCTRAQuest Hi SI Experts, My question pertains to the use of Cadence SPECCTRAQuest software for performing crosstalk simulations. The Default setting of Minimum Coupling Length is 300 mils, and I have been using 200 mils coupling length for my simulations. However, I have observed that when there are short length bends in the net (say when the net travels around a via), these short lengths are treated as separate sections of the net (Cline segments). If these sections are smaller than 200 mils then they are not included in the coupling calculation. Recently while simulating a design, I reduced the coupling length to 50 mils. This resulted in fourfold increase in the crosstalk. I would like to know if such phenomenon has been observed by other users too, and what is the coupling length they use in their simulations. Thanks. Regards, Ravinder Server PCB Development Hitachi Global Storage Technologies Email: Ravinder.Ajmani@xxxxxxxxxxxxxx ------------------------------------------------------------------ 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