Noise-cut LC filter for power converter with overlapping aligned coil patterns

摘要

A noise-cut filter having distributed inductances and distributed capacitances is provided wherein conductive spiral coil patterns are formed on the opposite surfaces of a dielectric sheet, such that the spiral coil patterns are aligned with each other in a direction perpendicular to the plane of the dielectric sheet, and a main circuit pattern is constructed by bonding a main circuit conductor to the spiral coil pattern formed on one of the opposite surfaces of the dielectric sheet. The main circuit conductor is formed by stamping with a punch press so that the conductor has a cross sectional area large enough to allow the passage of current of a main circuit, and has substantially the same shape as the spiral coil pattern. Further, a grounding wire is bonded to the spiral coil pattern formed on the other surface of the dielectric sheet, so that the grounding wire leads the current involving noises which flows from the main circuit pattern into the spiral coil pattern via the dielectric sheet, to a ground terminal.