From a PCB Fluxgate to an integrated micro Fluxgate magnetic sensor

In this paper a double axis micro fluxgate magnetic sensor is presented. The device represents an evolution of a PCB dual axis sensor previously realized. In the PCB version the experimental results exhibit excellent agreement with the simulations performed using a tool based on the finite element method. Using the same design approach a version of the double axis fluxgate structure to be realized in IC technology is here proposed. The accurate study of the magnetic field distribution allows a 75% area saving for the IC version with respect to a direct scaling of the PCB version. Imposing an external magnetic field of about 60 muT, the simulated differential output voltage of the micro-integrated fluxgate sensor achieves a peak value of 1 mV with 5 mA sinusoidal excitation current peak at 100 kHz