Check your units. One could be in pF/mil and the other pF/mm or something like that. -----Original Message----- From: tcoyle [mailto:TCoyle@xxxxxxxxxxxxxxxxxxxxxxx] Sent: Wednesday, October 31, 2001 11:11 AM To: si list Subject: [SI-LIST] Differences between HSPICE Field Solver and XTK Field Solver Dear Si List, I am using the microstrip equation in Howard Johnson's book to calculate the impedance. So given a w=8mil, t=1.37mil, and h=21mil, I get an impedance of about 100 ohms. When I use the XTK field solver, I get an L=14.5nH and a C=1.4pF. When I use the HSPICE field solver, I get an L=65nh and a C=6.5pF. They both give me an impedance of 100 Ohms but are quite different values. I think the XTK values are correct, so I'm wondering about the HSPICE field solver. Has anyone compared results between these two tools? Thanks Tim ------------------------------------------------------------------ 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: http://www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List archives are viewable at: http://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: http://www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List archives are viewable at: http://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