Patent ID: 7511594

Claim:
A noise filter for removing noise flowing in a signal wire located on a circuit board, the noise filter comprising: an insulator; a pair of external electrodes that are connected to the signal wire and are disposed on an outside of the insulator; a plurality of coils connected in series, disposed inside of the insulator, and having both ends thereof electrically connected to the external electrodes, respectively; and a capacitor connected in parallel to at least one of the plurality of coils; wherein each of the plurality of coils includes a plurality of coil conductors disposed in the insulator, the plurality of coil conductors being arranged in a spiral configuration and connected to each other through a via hole; and the capacitor includes a shield electrode and a capacitance-forming electrode opposed to each other through the insulator, the shield electrode being located between upstream and downstream coils of the plurality of coils and commonly electrically connected to both the upstream and downstream coils, the capacitance-forming electrode being electrically connected to one of the pair of external electrodes.