For different loading conditions (as a first pass) you could view the detailed section of our report as referenced in previous email. In this section you will find Impedance under various loading scenarios which will inform you whether or not there is different coupling between neighbor lines. This report gives you: Zg (Zgrounded) -all other conductors are grounded Z(effective) -all conductors are loaded signals Zf (Zfloated) -all other conductors are floated (or stubbed) As a second pass (if these values significantly differ) is to run the model in SPICE (you can control all loading scenarios), and from the SPICE results deduce the capacitive coupling directly. Brian --- In si-list@xxxxxxxxxxxxxxx, yoni tzafrir <imyonitz@xxxx> wrote: > o.k. > after using this web calculator, i got capacitance of 1.557pf/inch, i also got Tpd 0.1382 ns/inch. my line length is 1.7inch. relaying on previous discussions from the Si-list, i assume that just multiplying the 1.7 in capacitance (1.557pf/inch) would be wrong, because it is based on the wrong assumption that all the line will be loaded at the same time. > what should it be, then? > Michel Perez <michel.perez@xxxx> wrote: > Try this > > http://www.emclab.umr.edu/pcbtlc/index.html > > -----Original Message----- > From: yoni tzafrir [mailto:imyonitz@xxxx] > Sent: Tuesday, November 23, 2004 11:00 AM > To: si-list@xxxx > Subject: [SI-LIST] MicroStrip capacitance > > > hi all, > how do i caluculate the capacitance of a MicroStrip on a PCB? > > > --------------------------------- > Do you Yahoo!? > The all-new My Yahoo! - Get yours free! > > ------------------------------------------------------------------ > To unsubscribe from si-list: > si-list-request@xxxx 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@xxxx 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 > > > > > > > --------------------------------- > Do you Yahoo!? > Discover all that's new in My Yahoo! > > ------------------------------------------------------------------ > To unsubscribe from si-list: > si-list-request@xxxx 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@xxxx 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 ------------------------------------------------------------------ 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