4 Tools for determining the best magnet and sensor distance

To maximize sensing accuracy, select magnet-to-sensor distances and magnet specifications so that the sensed magnetic flux density uses as much of the device’s magnetic range as possible, while still ensuring that the maximum magnetic flux density produced in the system is within the sensor’s magnetic range. The process of selecting magnet-to-sensor distances and magnet specifications is often an iterative process – modifying parameters until one of the magnetic range options of the linear Hall-effect sensor can properly sense the generated magnetic flux density.

There are multiple options for determining the magnetic flux density versus the distance relationship for iterative adjustment. Calculator tools such as TI’s magnetic sensing proximity tool can calculate the magnetic flux density for common magnet-to-sensor configurations, including head-on and slide-by configurations.