The other problem with the suggested circuit, is that the LVPECL driver sees an effective load of 25 ohm load to something higher than Vtt = Vcc-2V. This probably lets the output driver turn off when it goes low. Most ECL outputs aren't supposed to turn off. You won't get the full LVPECL output swing. Regards, Andy ------------------------------------------------------------------ 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: http://www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List archives are viewable at: http://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