A MAGNETIC SENSOR WITH CURRENT-CONTROLLED SENSITIVITY AND RESOLUTION

In this paper we present a novel split-current magnetic sensor (bulk H all plate operated in the current mode) with on-chip circuitry, fabric ated in an industrial 2 mu m CMOS process. The sensor consists of a lo w-doped resistive path with one input and three output terminals. The on-chip circuit controls the biasing of the sensor, calculates the dif ference between the currents flowing through the outer output terminal s and provides an output voltage proportional to the applied magnetic field. We demonstrate that the sensitivity and the noise performance o f the proposed device can be tuned by changing the ratio between the b ias currents applied to the input and to the central output terminal, while keeping the power consumption constant. Supporting numerical sim ulations based on a finite-element method and experimental results on an integrated prototype are reported as well.