Do remember, though, that the Leff is a partial inductance - if it is = truly a floating plane, at the end of the plane boundary, there will be = another inductance contribution, unless there is a stitch to the other = reference. -----Original Message----- From: Loyer, Jeff=20 Sent: Friday, May 16, 2003 11:33 AM To: jaudet@xxxxxxxxxx; si-list@xxxxxxxxxxxxx Subject: [SI-LIST] Re: J.L. Prince (Influcence of a floating plane......) Arizona university A quick note, since no-one else replied. This is contrary to my intuition and what a simple XFX simulation shows. = =3D Adding a 2nd plane above the signal lowers Leff in that simulation. = =3D So, I'm surprised also. without plane above: i j Lij Cij Ze Zo Se So Fwdx =3D Rvsx =3D20 from to (nh/in) (pf/in) (ohms) (ohms) (ns/ft)(ns/ft) (s/s) =3D (v/v)=3D20 -------------------------------------------------------------------------= =3D - 1 1 8.963 1.363 81.09 - 1.33 - - - with plane (conductor 2)above=3D20 i j Lij Cij Ze Zo Se So Fwdx =3D Rvsx =3D20 from to (nh/in) (pf/in) (ohms) (ohms) (ns/ft)(ns/ft) (s/s) =3D (v/v)=3D20 -------------------------------------------------------------------------= =3D - 1 1 7.076 3.075 49.35 - 1.72 - - - 1 2 0.506 2.378 104.25 34.71 0.87 2.27 -0.890 =3D 0.500 2 2 1.018 16.383 8.18 - 1.49 - - - Jeff Loyer -----Original Message----- From: Jean Audet [mailto:jaudet@xxxxxxxxxx] Sent: Wednesday, May 14, 2003 9:56 AM To: si-list@xxxxxxxxxxxxx Subject: [SI-LIST] J.L. Prince (Influcence of a floating plane......) Arizona university Around 1996-1997, a presentation have been done by University of Arizona about the '' Influence of a Floating Plane on Effective Ground Plane in Thin Film Multilayer and Lead Frame package'' Into this presentation, the effective inductance simulation for a multilayer package having floating plane above is worst than whitout floating plane. Basically the structure (x-section) is the following Floating plane Signal Ground plane The Leff graph shows a Leff lower for structure whitout floating plane. = =3D I'm little surprise about the simulation results. Is someone has more data about that... or maybe M. Prince may reply if = =3D he is in the distribution list Also I have only a hard copy of this presentation, Is someone else has a soft copy ? Jean Audet Electrical Analysis World Wide Packaging & Test IBM Burlington Tel: 802-769-0835, tie line: 446-0835 Tel: 450-534-6317, tie line: 552-6317 E-mail: jaudet@xxxxxxxxxx ------------------------------------------------------------------ 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: =3D20 //www.freelists.org/archives/si-list or at our remote archives: http://groups.yahoo.com/group/si-list/messages=3D20 Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu =3D20 ------------------------------------------------------------------ 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: =20 //www.freelists.org/archives/si-list or at our remote archives: http://groups.yahoo.com/group/si-list/messages=20 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 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