  We propose a simple scheme for magnetic angular position sensor based on
current-induced spin-orbit torque effect. A full range detection of 360o is
realized with a pair of Hall crosses made of heavy metal/ferromagnet
heterostructures. The current axes of the two Hall crosses are aligned
orthogonal to each other such that when both devices are subject to a
rotational in-plane magnetic field, the differential Hall voltage due to
current pulses of opposite polarity exhibits a sine and cosine angular
dependence on the field direction, respectively. The field rotational angle is
then calculated from the sine and cosine output signals via the arctan2
function. A linear correspondence between the calculated and actual field angle
is obtained in the field range of 500-2000 Oe, with an average angle error of
0.38-0.65o.
