An inductive device comprises a soft magnetic core which consists of two E-shaped core halves (1), each of which comprises three parallel limbs (5, 7) which are interconnected by a yoke (9). The core halves (1) are arranged against one another by way of the free ends of the limbs (5, 7), a coil former (3) being provided around the central limbs (7). The outer limbs (5) extend between an upper boundary plane (25) and lower boundary plane (27), which planes extend parallel to the longitudinal directions of the limbs (5, 7) and the yokes (9), the distance between said planes being determined by the height (x) of the outer limbs (5) which is greater than the height (y) of the central limbs (7). The lower boundary of the central limb (7) is situated above or below the boundary plane (27) a distance such that the symmetry plane (31) of the central limbs (7) which extends parallel to the boundary planes (25, 27), is situated halfway between the upper boundary plane (25) and a plane (33) which extends parallel to the boundary planes and is from 0.1 to 1 mm above the lower boundary of the coil former (3). A winding (29) provided on the coil former (3) occupies exactly the space between the upper side of the outer limits (5) and the lower side, thus minimizing the height of the device. Such device may be, for example, a transformer or a choke coil.
An electrical device for mounting on a circuit board, such as an inductor or a transformer. The device contains first and second core halves which can be mated to one another. Each half contains an outer skirt attached to a back-plane, and a center core component which is attached to the back-plane in a position which is perpendicular to the back-plane and to the circuit board, when mounted. The center core component has a primary axis and a secondary axis, the secondary axis having a smaller dimension than the primary axis, and a cross-section with a ratio of length of primary axis to length of secondary axis of 1.1:1 to 3.5:1. The outer skirt, back-plane, and center core component all contain magnetic material, e.g. ferrite. A bobbin having a hollow center section with a cross-section of similar shape to the cross-section of the center core components is attached to first and second flanges, each of which flanges has wire mounting posts on its bottom edge. At least one coil is wound around the exterior surface of the bobbin. When the first and second core halves are mated, the center core components are inserted into the center section of the bobbin to form a magnetic core. The coil is attached to at least one pair of wire mounting posts to allow electrical connection to the circuit board.
A core for minimizing the circuit board footprint of a core-based component while also minimizing the total harmonic distortion exhibited by the component. The core includes a back wall portion, a central wall portion, and an outside wall portion. The back wall portion has a front and a back, with a lower end, an upper end, and a pair of sides extending between the lower and upper ends. The central leg portion protrudes from the front of the back wall portion, and the central leg portion is substantially centrally located on the front of the back wall portion. The outside wall portion protrudes from the front of the back wall portion. In one aspect of the invention, the central leg portion is elongated along a first axis extending between the upper and lower ends of the back wall portion. In another aspect of the invention, the central leg portion is spaced from the lower edge of the back wall portion.
