US Patent 7205860 Electromagnetic interface module for balanced data communication

Apparatus for reducing a common mode (CM) electromagnetic interference (EMI) in a balanced transmission line which carries a differential signal occupying a specified frequency band is described. The apparatus includes a first Single Ended Filter (SEF) operatively associated with a first path of the balanced transmission line, and a second SEF operatively associated with a second path of the balanced transmission line, wherein a ground terminal of the first SEF and a ground terminal of the second SEF are electrically connected to a local ground. Related apparatus and methods are also described.