Patent ID: 9344054
Filing Date: 2016-05-17
CPC Classification: H01P,H03H

Claim Text:
1. A common mode filter comprising: a differential transmission line including a first signal line and a second signal line, a first inductance element arranged in series in the first signal line, a second inductance element arranged in series in the second signal line, and a ground defining a reference with respect to the first signal line and the second signal line; a first resonant circuit arranged between the first inductance element and the ground; and a second resonant circuit arranged between the second inductance element and the ground; wherein the first resonant circuit includes a first LC series circuit including a first capacitance element connected to the first inductance element; the second resonant circuit includes a second LC series circuit including a second capacitance element connected to the second inductance element; the common mode filter includes: the first LC series circuit includes: the second LC series circuit includes the fourth inductance element; and a resonant frequency of the first resonant circuit and a resonant frequency of the second resonant circuit are frequencies at which the first resonant circuit and the second resonant circuit attenuate a common mode noise entering the differential transmission line, and the resonant frequencies of the first resonant circuit and the second resonant circuit are different from each other.