For position-sensing applications such as linear motor transport systems that must detect the position of a magnet sliding along a linear path, the geometry of the magnet and the relative air gap to the sensor influences the behavior of the magnetic field as the magnet passes by the sensor.

Additionally, in any system the sensing range must be maximized for each sensor to reduce component count and save cost. In smaller applications that require only a low quantity of sensors, often the cost of the single magnet can overwhelm the total cost of the sensors. However, designers can consider the use of a slightly larger magnet to reduce the total number of sensors in large arrays.

This application note discusses the placement, calibration, and sensing range of various magnet geometries and materials with 3D magnetic sensors, like the TMAG5170, TMAG5173-Q1, and TMAG5273, in linear arrays.