Common mode signal suppressing circuit and normal mode signal suppressing circuit

Abstract

A common mode signal suppressing circuit comprises: a first winding () inserted to a conductor line (); a second winding () that is inserted to a conductor line () and coupled to the first winding () through a magnetic core () and that suppresses common mode signals in cooperation with the first winding (); and a third winding () coupled to the first and second windings () through the core (). The common mode signal suppressing circuit further comprises a phase-inverted signal transmitting circuit () connected to the third winding () and to the conductor lines (). The phase-inverted signal transmitting circuit () detects a common mode signal on the conductor lines (), and supplies a phase-inverted signal to the third winding (), the phase-inverted signal having a phase opposite to the phase of the common mode signal.