Here is one example using the W element to call it...replace your parameters as needed. ********** W element *********** w1 in1 in2 gnd out1 out2 gnd FSmodel=junk +N=2 l=508mm ********** Matericals *********** .material diel dielectric er=4.1 losstangent=0.015 .material copper metal conductivity=58130000 ********** Shape *********** .shape rect rectangle width=0.1524mm height=0.01778mm; ********** Planes *********** .layerstack stack1_6 +layer=(copper,0.01778mm), layer=(diel,0.4064mm), +layer=(copper,0.01778mm) ********** Conductor *********** .model junk w modeltype=fieldsolver, +layerstack=stack1_6, fsoptions=opt1 +rlgcfile=task1_6.rlgc +conductor=(shape=rect,origin=(-0.3048mm,0.21209mm),material=copper) +conductor=(shape=rect,origin=(0.1524mm,0.21209mm),material=copper) -----Original Message----- From: tcoyle [mailto:TCoyle@xxxxxxxxxxxxxxxxxxxxxxx] Sent: Monday, October 29, 2001 3:49 PM To: si list Subject: [SI-LIST] Defining stackup in HSPICE Field Solver Dear SI List, I am trying to use the HSPICE internal field solver for a microstrip line. Here's my stackup: layer 1 - top layer 2 - gnd1 layer 3 - vcc1 layer 4 - vcc2 layer 5 - gnd2 layer 6 - bottom In XTK, I can list out the layers as they are and get the right impedence (100 ohms). But to do this in the field solver in HSPICE? >From the manual it seems I only define a ground layer and then a signal layer? So I tried this: ********** W element tline definition********** * * Define the board material * Losstangent = tan (delta) LOSSTANGENT=0.020 .MATERIAL diel1_fr4 DIELECTRIC ER=4.2 .MATERIAL diel2_fr4 DIELECTRIC ER=3.8 .MATERIAL copper METAL CONDUCTIVITY=5.8e+07 * Define the cross section of the trace as a rectangle * 1.0 oz copper (usually has height of 1mil), 8 mil wide .SHAPE rect RECTANGLE WIDTH=8mil, HEIGHT=1.37mil * Define the layer stackup * Layer = (material name, thickness) .LAYERSTACK microstrip_one_100 + LAYER=(copper,1mil) * ideal ground plane + LAYER=(diel1_fr4,21mil) * signal layer .FSOPTIONS opt1 PRINTDATA=yes + ComputeRo=yes ComputeRs=yes ComputeGo=Yes ComputeGd=yes + ACCURACY = HIGH .MODEL micro100 W MODELTYPE=Fieldsolver, +LAYERSTACK=microstrip_one_100 FSOPTIONS=opt1 +CONDUCTOR= (MATERIAL=copper, SHAPE=rect, ORIGIN= (0, 21mil)) ****** End of the W element definition ***************************************************** Is this the correct way to define the equivalent stackup? And what do I choose as my origin? Accroding to the output, I get an L value of 368nH, which is not right. Thanks to anyone who can help me out - 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: //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 ------------------------------------------------------------------ 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