Magnetic field sensor integrated circuit with integral ferromagnetic material

A magnetic field sensor, comprising:

• a lead frame comprising at least one die attach pad, an extension extending from a first side of the at least one die attach pad, and at least one lead extending from a second side of the at least one die attach pad substantially orthogonal to the first side of the at least one die attach pad;
• a semiconductor die attached to a surface of the at least one die attach pad of the lead frame and comprising a magnetic field sensing element;
• a non-conductive mold material comprising a thermoset and enclosing the semiconductor die, wherein the extension extends beyond the non-conductive mold material;
• and
• a ferromagnetic mold material secured to a portion of the non-conductive mold material, wherein the ferromagnetic mold material is tapered from a first end proximate to the lead frame to a second end distal and spaced from the lead frame and wherein the ferromagnetic mold material is further secured to, and is in direct contact with the extension, wherein the extension comprises a bend enclosed by the non-conductive mold material and a barb extending from the bend at a non-zero angle from a plane parallel to the surface of the die attach pad to which the semiconductor die is attached into the ferromagnetic mold material to terminate in the ferromagnetic mold material, wherein the extension provides a securing mechanism for engaging the ferromagnetic mold material.