Patent ID: 6683523
Filing Date: 2004-01-27
Classification: H01F

Abstract:
A laminated impedance device comprising:a high-permeability coil unit including a plurality of magnetic layers made of a relatively-high-permeability material and a plurality of coil patterns laminated together, said high-permeability coil unit including at least first and fourth coil portions; and a low-permeability coil unit including a plurality of magnetic layers made of a relatively-low-permeability material and a plurality of coil patterns laminated together, said low-permeability coil unit including at least second and third coil portions; wherein the first coil portion of the high-permeability coil unit, the second coil portion of the low-permeability coil unit, the third coil portion of the low-permeability coil unit, and the fourth coil portion of the high-permeability coil unit are electrically connected in series in a sequential manner to define a spiral coil, and the first coil portion and the fourth coil portion of said high-permeability coil unit are connected to one of an input external electrode and an output external electrode.