Semiconductor device with passivated magnetic concentrator

A described example includes: a semiconductor die (FIG. 5, 505) including a Hall sensor (506) arranged in a first plane that is parallel to a device side surface of the semiconductor die; a passivated magnetic concentrator (512) including a magnetic alloy layer (515) formed over the device side surface of the semiconductor die, the upper surface of the magnetic alloy layer covered by a layer of polymer material (517); a backside surface of the semiconductor die opposite the device side surface mounted to a die side surface of a die pad (502) on a package substrate, the semiconductor die having bond pads on the device side surface spaced from the magnetic concentrator; electrical connections (513) coupling the bond pads of the semiconductor die to leads (501) of the package substrate; and mold compound (503) covering the magnetic concentrator, the semiconductor die, the electrical connections, a portion of the leads, and the die side surface of the die pad.