If you have a problem solved in HFSS - you can contact their Apps Engineers to figure out how to get Zo from your solution. Or - Use a 2D extractor. Best Regards Charles Grasso Senior Compliance Engineer Echostar Communications Corp. Tel: 303-706-5467 Fax: 303-799-6222 Cell: 303-204-2974 Pager/Short Message: 3032042974@xxxxxxxx Email: charles.grasso@xxxxxxxxxxxx; Email Alternate: chasgrasso@xxxxxxxx -----Original Message----- From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx] On Behalf Of ryansatrom Sent: Wednesday, May 10, 2006 9:58 AM To: si-list@xxxxxxxxxxxxx Subject: [SI-LIST] Re: Microstrip Trace under Nickel Aubrey- Yes, thank you very much for that last explanation. I was=20 struggling to understand the relationship because I couldn't find=20 anywhere the inductance increasing by 600X. Running simple=20 hypothetical simulations in HFSS has shown that TOTAL inductance is=20 higher at low frequencies, but starts to converge as frequencies=20 increase - just as you suggested. Thanks for the help. That 600 value was really causing confusion. =20 But now at least i'm starting to understand the relationship. --- In si-list@xxxxxxxxxxxxxxx, <Aubrey_Sparkman@...> wrote: > > Let's be a little careful; it's the internal inductance that goes=20 up. > The permeability of 600 affects only the magnetic fields that=20 penetrate > the nickel; therefore impacting crosstalk and skin effect. IE, the > higher the frequency, the less the effect. >=20 > So I am NOT saying the TOTAL (internal + external) inductance goes=20 up > 600X. And since nickel purity and processing affect the=20 permeability, > you need to investigate the range of possible values.=3D3D20 > =3D3D20 >=20 >=20 > Aubrey Sparkman=3D3D20 > Enterprise Engineering Signal Integrity Team > Dell, Inc.=3D3D20 > Aubrey_Sparkman@...=3D3D20 > (512) 723-3592 >=20 > The Greatest Pleasure in Life is Doing what People say can't be=20 done... >=20 > -----Original Message----- > From: si-list-bounce@... [mailto:si-list-bounce@...] > On Behalf Of steve weir > Sent: Wednesday, May 10, 2006 10:08 AM > To: ryan.satrom@...; si-list@... > Subject: [SI-LIST] Re: Microstrip Trace under Nickel >=20 > Ryan the Telegrapher's equations still hold. Provided the=20 material does > not saturate, ignoring fringing for a rectangular section: L=3D3D3D = =3D3D > u0*uR*H/X > UMR has a web calculator that if I recall correctly allows you to=20 input > uR. >=20 > So, for a uR of 600 and no saturation, the inductance would go up=20 by > 600X and the impedance by about 24-25X. You can see that it=20 doesn't > take much nickel to really throw things off. >=20 > Steve. > At 07:53 AM 5/10/2006, ryansatrom wrote: > >Aubrey- > > > >I am well aware of the definition of permeability. However,=20 i'm=3D3D20 > >struggling with this relationship. For example: > > > >Capacitance increases proportionally to dielectric contstant=3D3D20 > >(permittivity). > > > >So if permeability does the same to inductance as permittivity=20 does to=3D3D20 > >capacitance, then then inductance of a signal-return path made=20 purely=3D3D20 > >of nickel (no plating, used strictly for example) has 600 times=20 the=3D3D20 > >inductance of the same signal-return path made from gold? > > > >Are you saying that is true? > > > > > > > > > >------------------------------------------------------------------ > >To unsubscribe from si-list: > >si-list-request@... 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@... with 'help' in the Subject field > > > >List FAQ wiki page is located at: > > http://si-list.org/wiki/wiki.pl?Si-List_FAQ > > > >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 > > >=20 > ------------------------------------------------------------------ > To unsubscribe from si-list: > si-list-request@... with 'unsubscribe' in the Subject field >=20 > or to administer your membership from a web page, go to: > //www.freelists.org/webpage/si-list >=20 > For help: > si-list-request@... with 'help' in the Subject field >=20 > List FAQ wiki page is located at: > http://si-list.org/wiki/wiki.pl?Si-List_FAQ >=20 > List technical documents are available at: > http://www.si-list.org >=20 > List archives are viewable at: =3D3D20 > //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 > =3D3D20 > ------------------------------------------------------------------ > To unsubscribe from si-list: > si-list-request@... with 'unsubscribe' in the Subject field >=20 > or to administer your membership from a web page, go to: > //www.freelists.org/webpage/si-list >=20 > For help: > si-list-request@... with 'help' in the Subject field >=20 > List FAQ wiki page is located at: > http://si-list.org/wiki/wiki.pl?Si-List_FAQ >=20 > List technical documents are available at: > http://www.si-list.org >=20 > 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 > ------------------------------------------------------------------ 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 FAQ wiki page is located at: http://si-list.org/wiki/wiki.pl?Si-List_FAQ 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 FAQ wiki page is located at: http://si-list.org/wiki/wiki.pl?Si-List_FAQ 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