My guess is that you probed the driver to resistor junction, instead of the resistor to tx-line junction. Steve. At 11:59 AM 9/9/2004 -0700, V S wrote: >I am trying to use SigXplorer for a PCI reflected wave >switching. I am comparing the waveform of the >SigXplorer and the hspice at the TRANSMITTER. Although >the waveforms at the receiver look similar, the >waveform at the transmitter in the SigXplorer looks >different and unexplainable. I expect the initial >voltage at the tranmitter to be > >Vo = Vcc*Zo/(Zo+R) > >where R is the sum of the drive strength and the >series termination resistance and > >is equal to Zo. Thus, I expect it to be 1.65V ( 1/2 of >3.3 V) and I am getting 1.65V in hspice. But in >SigXplorer, I am am getting it about 2.58V. Can anyone >try any PCI clock or data and confirm is it so and why >? > > >For example try Texas Instrument ibis model for 33 MHz >Clock Driver CDC960 model CDC960_T5 ( it can be >downloaded from TI website). > > > ____ > / \ > __/ \__ ____ 2.58V > / \ > / \ > / \ > / \ > > > SigXplorer waveform at Transmitter > > > ____ > / \ > / \ > __/ \__ ____ 1.65 V > / \ > / \ > / \ > >HSpice waveform at Transmitter > > >VS > > > > > >__________________________________ >Do you Yahoo!? >Yahoo! Mail - 50x more storage than other providers! >http://promotions.yahoo.com/new_mail >------------------------------------------------------------------ >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 > ------------------------------------------------------------------ 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