Precise AMR magnetometer for compass

Abstract

AMR sensors gain growing popularity in linear applications such as compassing (Tumaski and Ripka). We discuss techniques, how to achieve precision required for 0.2 deg azimuth error in wide temperature range. While linearity of 80 ppm FS and sensitivity tempco of 20 ppm/K can be achieved by using feedback compensation, offset drift and crossfield error can be lowered to nT level by periodical flipping.