Novel Power-Saving Algorithm for AMR Magnetometer With Fast Settling Feedback Loop

Power consumption plays a pivotal role in a variety of applications that use magnetometers (e.g., space applications, wearables, <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text {drones}, \ldots $ </tex-math></inline-formula>). In this article, a novel approach to reduce power consumption in magnetometers is proposed. We primarily focus on the anisotropic magneto-resistance (AMR) based magnetometer, which was subjected to a series of tests. Nevertheless, this algorithm is broadly applicable to any magnetometer that employs a fast-enough feedback compensation. In precise magnetometers, feedback compensation is almost always utilized to obtain stability and linearity. Traditionally, this feedback compensation remains active for the entire duration the magnetometer is powered on. We propose an algorithm that disables this feedback for the majority of the time and enables it briefly only when necessary. This approach leads to a significant reduction in power consumption (20%) while maintaining full accuracy and low noise.