Alex, Usually the price to pay is an increase in power dissipation. Bigger swing means more current supplied to a fixed load. Thus for shorter traces why use more power than necessary and also avoid the signal integrity/emission problems you alluded to below. -------------------------------------------------------------- | Bill Cohen | Toshiba America Electronic Components, Circuit Design Group | email: wcohen@xxxxxxxx | office: (508) 486-1031 fax: (508) 481-8828 -------------------------------------------------------------- Hello, I have a question regarding the output swing control for some modern gigabit serdeses which are now available. By using this feature one can clearly improve the eye opening at the receiver, especially for long traces but the question is which is the price to pay? Because there is always one... One effect would be the higher emissions due to faster edges, but I do not believe this should be so strong. Is it a problem for shorter traces? So if I have a 30" trace and swing control helps, if I use the same swing for a 3" trace it is a problem? Thank you, Alex ------------------------------------------------------------------ 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