The ATS622LSB is an optimized Hall-effect sensing integrated circuit and magnet combination that provides a user-friendly solution for true zero-speed digital gear-tooth sensing. The sensor subassembly consists of a plastic shell that holds together a samarium-cobalt magnet, a pole piece, and a Hall-effect sensor that has been optimized to the magnetic circuit. This small package can be easily assembled and used in conjunction with a wide variety of gear shapes and sizes.