Patent ID: 7009482

Claim:
A controlled inductance device for use in an electrical circuit, comprising: magnetically permeable core, said core comprising a substantially right cylindrical shape and having upper and lower core elements that meet substantially at a first plane intersecting said right cylindrical shape and forming an internal channel adapted to accommodate at least one winding, said upper and lower elements each having a central, substantially cylindrical portion, the mating surface of the portion of one of said upper and lower elements being substantially planar, the mating surface of the portion of the other of said elements being substantially stepped so as to form a stepped gap with said planar mating surface; at least one winding disposed substantially within said internal channel; and a terminal array having a plurality of terminals in electrical communication with said at least one winding, said array being configured for mounting said inductance device to respective ones of conductive elements of a substrate; wherein said controlled inductance device produces an inductance-current profile having (i) a first portion with a substantially constant first inductance value corresponding to low dc current through said device), (ii) a second substantially vertical portion with decreasing inductance as dc current increases, (iii) a third portion with substantially constant second inductance value at higher dc current, and (iv) a fourth portion wherein said device core is completely saturated.