Hi Bipin, I would not use stripline as a way to calculate the delay I would be afraid to over estimate it. ( you actually ahve an embedded microstrip) In your case what plays a role is the fact that you have a dielectric on the top of the S1. The dielectric will change the field distribution or if you like the effective dielectric costant and so also the other trasmission line parametrs will be affected. Top layer will not play a very significant role unless you do not have a copper area on the top of your signal on S1 To make some simulation you may want go on Ansoft web site and download Maxwell SV that is free It allow you to make 2D analysis that should be enough to reply to your question Hope this help Giancarlo ----- Original Message ----- From: "Bipin Dhavale" <bipindhavale@xxxxxxxxx> To: <si-list@xxxxxxxxxxxxx> Sent: Wednesday, September 29, 2004 12:13 PM Subject: [SI-LIST] Propagation delay on embedded microstrip Hi Everyone, In the stackup shown below what propagation delay should I consider in Signal Layer S1 ? ---------------Top (Signal) ---------------S1(Signal) ---------------Plane(Pwr or gnd) Thickness between Top to S1 is equal to S1 to Plane What would be the best assumption ? a] Microstrip b] Close to microstrip c] Stripline d] Close to stripline e] Inbetween stripline & microstrip Also If i consider S1 layer as deeply embedded (S1 to Plane >>> Top to S1) Can I safely consider propagation delays in layer S1 as close to stripline ? Thank you, Bipin ------------------------------------------------------------------ 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