A plurality of steps of LC parallel resonant circuits(8, 9) are composed of a plurality of coils(11, 13), which are connected in series and are electrically connected respectively with external electrodes(6, 7) at both ends, and capacitors(12, 14) which are connected to the coils in parallel. The LC parallel resonant circuits are formed in an insulator(4) in a status where the LC parallel resonantcircuits are successively cascade-connected with a signal wiring(2). Each of the LC parallel resonant circuits(8, 9) is set to have different resonant frequency. A shield electrode(23) is provided between the coils(11, 13) to serve also as a capacitance forming electrode for preventing mutual magnetic coupling.