Doesn't the concepts of over-damped (undershoot), under-damped (ringback), and critically damped systems apply here? Aubrey Sparkman=20 Enterprise Engineering Signal Integrity Team Dell, Inc.=20 Aubrey_Sparkman@xxxxxxxx=20 (512) 723-3592 The Greatest Pleasure in Life is Doing what People say can't be done... -----Original Message----- From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx] On Behalf Of art_porter@xxxxxxxxxxx Sent: Monday, May 22, 2006 11:23 AM To: leeritchey@xxxxxxxxxxxxx; madhusudhan@xxxxxxxxxx; si-list@xxxxxxxxxxxxx Subject: [SI-LIST] Re: Ring back I would argue that there is a difference. Undershoot is defined by the = =3D IEEE in standard 181-2003 as "3.1.49 undershoot: A waveform aberration = =3D within a post-transition aberration region or pre-transition aberration =3D region that is less than the lower state boundary for the associated = =3D state level." In layman's terms, undershoot does not require a preceding =3D overshoot. Ringback to me, again in simple laymans' terminology, is the =3D first (or lowest) dip AFTER an initial overshoot. "Ringback" to = me =3D implies that there is some resonance, so one would expect to see a = =3D damped sinusoid following a transition. There is no IEEE standard definition for "Ringback," but I believe it = =3D has been defined in some semiconductor manufacturers' data sheets and = =3D app notes. =3D20 Art Porter Agilent Technologies =3D20 -----Original Message----- From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx] =3D On Behalf Of Lee Ritchey Sent: Monday, May 22, 2006 9:02 AM To: Madhusudhan Kulkarni; si-list@xxxxxxxxxxxxx Subject: [SI-LIST] Re: Ring back Ringback is just another name for undershoot. I don't know why someone =3D had to invent another name for something that already had a name. When you have undershoot and you use series terminations, the terminator value it too high or the output impedance of the driver is too high. = =3D When you have undershoot and you use parallel terminations, the value of the terminator is too low. Fix which ever problem you have by changing the value appropriately. > [Original Message] > From: Madhusudhan Kulkarni <madhusudhan@xxxxxxxxxx> > To: <si-list@xxxxxxxxxxxxx> > Date: 5/22/2006 9:28:26 AM > Subject: [SI-LIST] Ring back > > Hi, > How to solve ringback problem and what is the disadvantages of =3D ringback > ------------------------------------------------------------------ > 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: =3D20 > //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 > =3D20 ------------------------------------------------------------------ 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: =3D20 //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 =3D20 ------------------------------------------------------------------ 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