A Hall Sensor-Based Current Measurement Microsystem with Continuous Gain Calibration
A novel technique for the continuous calibration of the sensitivity of Hall sensors is presented. Using an integrated coil and a new modulation/demodulation scheme, the sensitivity is measured and its drift eliminated. The obtained thermal drift is 50 ppm/degrees C, which corresponds to a reduction by a factor of 6-10 compared to the previous state of the art. The sensitivity drift due to purely mechanical stresses and ageing is also cancelled.