Patent ID: 7135949

Claim:
An electrical device for mounting on a printed circuit board (PCB) defining a mounting plane, the device including a magnetic core structure of first and second core parts and at least one coil within the magnetic core structure, each one of the first and second core parts comprising: (a) a backwall and an outer skirt portion extending from the backwall, the core part being formed of a first magnetic material; (b) an asymmetric center core element formed of a second magnetic material and extending from the backwall in the same direction as the outer skirt along a longitudinal axis parallel with the mounting plane and including a centroid of the center core element, the outer skirt and the center core element defining a generally uniform volume for the at least one coil, a cross-section of the center core element being asymmetric relative to a dividing plane and including the longitudinal axis, such that a greater portion of the mass of the center core element lies on one side of the dividing plane and a lesser portion of the mass of the center core element lies on an opposite side of the dividing plane; (c) the at least one coil defining a longitudinal lumen shaped to be similar to the cross-section of the center core element and sized to receive the center core element in a close-fitting relationship when the device is assembled and having terminal ends arranged to connect to connection traces formed on the PCB; and (d) outer face areas of each outer skirt portion being in substantial contact when the first and second core halves are brought together upon assembly of the device.