Hi Juergen, You can find lots of application notes especially with respect to process variation on differential pairs here: www.polarinstruments.com/support/cits/cits_index.html In particular this one may be of interest: How measured impedance may vary from field solver calculations when using woven glass reinforced <http://www.polarinstruments.com/support/cits/AP139.html>laminates www.polarinstruments.com/support/cits/AP139.html And this note: Copper thickness, edge coupled lines and characteristic <http://www.polarinstruments.com/support/cits/AP151.html>impedance www.polarinstruments.com/support/cits/AP151.html Hope this helps.... Kind regards Martyn Gaudion www.polarinstruments.com T: +44 1481 253081 F: +44 1481 252476 M: +44 7710 522748 E: martyn@xxxxxxxxxxxxxxxxxxxx ============================================ Controlled Impedance & Signal integrity tools for the Printed circuit fabrication industry ============================================ At 19:00 02/10/2003, you wrote: >I am seeking help in finding enlightenment regarding electrical >performance pros and cons and how manufacturing tolerances play a role >when comparing side by side and tandem differential pairs. I'd appreciate >your opinion, experience, analysis, pointers to papers and articels, etc. > >In return, I would offer to share a summary of the finding/discoveries >with interested parties. > >Thanks > >Juergen > > > >------------------------------------------------------------------ >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 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 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