Hi: Any body know what is a typical value for the dielectric constant as well as loss tangent of the solder mask? Thanks. Best Regards, Michael Chan Hewlett-Packard Corp. Houston, TX -----Original Message----- From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx] On Behalf Of Grasso, Charles Sent: Friday, February 13, 2004 1:13 PM To: 'ariazi@xxxxxxxxxxxxxxx'; 'si-list@xxxxxxxxxxxxx' Subject: [SI-LIST] Re: On the effect of solder mask on Zo - Update Dear Abe, In the P&D article Eric was using a 20mil wide trace with a 10 mil spacing. In the 2D solver article, Eric was using a 5mil, trace with a 2.5mil spacing. So the structure counts.!! Best Regards Charles Grasso Senior Compliance Engineer Echostar Communications Corp. Tel: 303-706-5467 Fax: 303-799-6222 Cell: 303-204-2974 Email: charles.grasso@xxxxxxxxxxxx; =20 Email Alternate: chasgrasso@xxxxxxxx =20 -----Original Message----- From: Abe Riazi [mailto:ariazi@xxxxxxxxxxxxxxx]=20 Sent: Friday, February 13, 2004 11:14 AM To: 'si-list@xxxxxxxxxxxxx' Subject: [SI-LIST] Re: On the effect of solder mask on Zo Dear Charles and others In a column by Dr. Eric Bogatin ( "When Accuracy Counts" Printed Circuit Design & Manufacture", May 2003, P. 36 ), it is stated that Zo decreases by about one Ohm per one mil of soldermask thickness. Regards, Abe Riazi ServerWorks -----Original Message----- From: Grasso, Charles [SMTP:Charles.Grasso@xxxxxxxxxxxx] Sent: Friday, February 13, 2004 7:49 AM To: 'si-list@xxxxxxxxxxxxx' Subject: [SI-LIST] On the effect of solder mask on Zo Its about 3ohms per mil. The upper limit is 7mils at this point the soldermask is essentially infinite. Quite significant I would think. =20 Source : Verifying the accuracy of 2S solvers on Zo Calculation - Dr Eric Bogatin. Slides available from the GigaTest website : http://www.gigatest.com <http://www.gigatest.com/>=20 =20 Best Regards Charles Grasso Senior Compliance Engineer Echostar Communications Corp. Tel: 303-706-5467 Fax: 303-799-6222 Cell: 303-204-2974 Email: charles.grasso@xxxxxxxxxxxx; <mailto:charles.grasso@xxxxxxxxxxxx; %20> =20 Email Alternate: chasgrasso@xxxxxxxx <mailto:chasgrasso@xxxxxxxx>=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 technical documents are available at: http://www.si-list.org List archives are viewable at: =20 //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 =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 technical documents are available at: http://www.si-list.org List archives are viewable at: =20 //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 =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 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