Hi All Could anyone put some light on what criteria should be used to decide for a serial interface that 1. It should use AC or DC coupling 2. How to decide the common mode voltage. 3. how much should be the difference between Vcm of Tx and Rx. What criteria determines this difference in multi GHz range. Thanks Ajay Sent from my Huawei Mobile------------------------------------------------------------------ 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 forum is accessible at: http://tech.groups.yahoo.com/group/si-list List archives are viewable at: //www.freelists.org/archives/si-list Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu