Regarding Rahul's point #1 below: I'm stating the obvious here, so pardon me, but you can't go adding up the total capacitance of a t-line, if placed in between each capacitor in your equivalent t-line model is an inductor. I suggest reading a good book on transmission lines. (t-lines are amazing.) Regards, Jim Honeywell > Hello all, > Thanks for the reply, i understood it. One more related point to clearify . > > I am doing IO driver simulation running at frerquency less that 250 > Mhz . Capacitive load at farend is given equal to 4pF along with > txline of 3cm. (Z0 = 50, Co = 1.5pF / Cm , Td = 60pS / cm ) > > 1. Can i take equivalent capacitance to 4pF + (1.5pF *3) = 8.5pF for > my first order IO calculations. ( Transitions ) . > > 2. I am taking ELDO ( simulator ) lossless txline model which takes Z0 > and Td as parameter. By doing this can i assume safely that i have > taken account of Transmission line capacitance of 4.5pF. > Or do i need to take lossy transmission line model and ask for more parameters. > > Thanks for the help. > Rahul > > > > > > <rtatikola@xxxxxxxxx> wrote: > >> Rahul, >> >> Definitely not frequency dependent. The units show that it is dependent on >> the length of the transmission line and calculation is based on >> cross-section (2D approximation). >> >> Ramani >> >> On Sat, Oct 24, 2009 at 5:34 AM, rahul kumar <rahul05kumar@xxxxxxxxx> wrote: >> >> >>> Hello all, >>> I have seen in standards quoting transmission line capacitance equal to >>> 1.5pF per cm . How this number is calculated? >>> Is this value frequency dependent? transition dependent ? >>> >>> Kindly help. >>> Suggest link to know more information about the same. >>> >>> Thanks >>> >>> >>> ------------------------------------------------------------------ >>> 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 technical documents are available at: >>> http://www.si-list.net >>> >>> 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 technical documents are available at: > http://www.si-list.net > > 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 > > > > -- Steve Weir IPBLOX, LLC 150 N. Center St. #211 Reno, NV 89501 (866) 675-4630 Business (707) 780-1951 Fax http://www.ipblox.com A Teraspeed Consulting Group LLC Partner Teraspeed Consulting Group 121 North River Drive Narragansett, RI 02882 (401) 284-1827 Business (401) 284-1840 Fax Teraspeed Labs 13610 SW Harness Lane Beaverton, OR 970 08 (503) 430-1065 Business (503) 430-1285 Fax A Teraspeed Consulting Group LLC Partner http://www.teraspeed.com This e-mail contains proprietary and confidential intellectual property of IPBLOX LLC ------------------------------------------------------------------------ ------------------------------ Teraspeed(R) is the registered service mark of Teraspeed Consulting Group LLC ------------------------------------------------------------------ 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 technical documents are available at: http://www.si-list.net 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 technical documents are available at: http://www.si-list.net 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 technical documents are available at: http://www.si-list.net 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