US 6,137,390 A
Inductors with minimized EMI effect and the method of manufacturing the sameGeneral
US 6,137,390 A
Inductors with minimized EMI effect and the method of manufacturing the same
Tech Center:
2800 Semiconductors/Memory, Circuits/Measuring and Testing, Optics/Photocopying, Printing/Measuring and Testing
Examiner:
Michael L. Gellner
Art Unit:
2832 Electrical Circuits and Systems
Agent:
Inventors:
MEAN-JUE TUNG; YU-TING HUANG
Assignee:
Priority:
05/03/99
Filed:
05/03/99
Granted:
10/24/00
Expiration:
05/03/19
Abstract
An inductor with enhanced inductance and reduced electromagnetic inductance (EMI) interference. It contains: (a) a magnetic core; (b) an electrically conducting coil wound about the magnetic core; and (c) a magnetic resin layer compression-molded to embed at least a portion of the outer periphery of the electrically conducting coil. The magnetic resin contains a magnetic powder dispersed in a polymer resin. For relatively low inductance inductors, instead of being of a hard metal rod, the magnetic core can be made of the same material as the magnetic resin. The inductance of the inductor can be controlled by controlling the magnetic permeability of the magnetic resin or the thickness of the magnetic resin layer, or both. The magnetic core can be a magnetic metal/metal oxide core, or a consolidated magnetic core made of the same or different magnetic resin as the magnetic resin layer. A metal magnetic sheath can be further provided outside of the magnetic resin layer.