Hi, I have made a 100 Ohm differential microstrip trace using the HSPICE field solver. I am trying to get the field solver to give loss results, such as Rs and Ro. But each time I run HSPICE, I only get L and C values. Can anyone see what I might be doing wrong? I am using version 2001.2 Thanks, Tim * * Define the board materials .MATERIAL dielectric_fr4 DIELECTRIC ER=4.2 LOSSTANGENT=0.02 .MATERIAL copper METAL Conductivity=5.813E7 * Define the cross section of the traces as a rectangle * 1.0 oz. copper has height of 1.44mils .SHAPE rect RECTANGLE WIDTH=6mil, HEIGHT=1.2mil * Define the layer stackup * Layer=(material name, thickness) .LAYERSTACK diff_micro + LAYER=(PEC,1um) * ideal air (top layer) + LAYER=(dielectric_fr4,3.5mil) * dielectric layer * Define Field Solver Options .FSOPTIONS opt1 PRINTDATA=yes + ACCURACY=HIGH + ComputeRo=yes ComputeRs=yes ComputeGo=Yes ComputeGd=yes * Model Definition .MODEL diff_microstrip W MODELTYPE=FieldSolver, + LAYERSTACK=diff_micro, FSOPTIONS=opt1, + RLGCFILE=diffmicro.rlgc + CONDUCTOR=(SHAPE=rect, ORIGIN=(0,3.5mil)), + CONDUCTOR=(SHAPE=rect, ORIGIN=(100mil,3.5mil)) * *SYSTEM_NAME : diff_microstrip * * Half Space, air * ------------------------------------ Z = 8.99e-05 * dielectric_fr4 H = 8.89e-05 * ------------------------------------ Z = 1e-06 * //// Bottom Ground Plane /////////// * ------------------------------------ Z = 0 * L(H/m), C(F/m), Ro(Ohm/m), Go(S/m), Rs(Ohm/(m*sqrt(Hz)), Gd(S/(m*Hz)) .MODEL diff_microstrip W MODELTYPE=RLGC, N=2 + Lo = 2.88615e-07 + 6.05346e-10 2.88615e-07 + Co = 1.15222e-10 + -4.70212e-14 1.15222e-10 + Ro = 0.00000e+00 + 0.00000e+00 0.00000e+00 + Go = 0.00000e+00 + -0.00000e+00 0.00000e+00 + Rs = 0.00000e+00 + 0.00000e+00 0.00000e+00 ------------------------------------------------------------------ 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