New Field Sensors Based on Combined Fluxgate- Hall Effect Magneto-Transport Arrangement

A novel 2D magnetic field sensor is presented that is based on a combined Fluxgate/Hall-Effect arrangement. The proposed device involves a thin, isotropic, circular magnetic core, the magnetization of which is driven to saturation, by means of a rotating excitation-field produced by four printed planar coils. That way, the core magnetization rotates, without Barkhausen jumps inducing two orthogonal harmonic flux-density signals that are sensed respectively by two pairs of Hall devices positioned at the edge of the core. The presented sensor incorporates discrete Hall devices and electronic circuitry, as well as a 200 mm diameter amorphous core, packaged on a PCB board. However, the system can easily be implemented on a single silicon-chip, by means of standard CMOS technologies. In this case, the amorphous core is attached onto the chip that contains the Hall devices, planar coils, and electronic circuitry, according to a state-of-art low-temperature post-process