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 module 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.

The integrated circuit incorporates a dual-element Hall-effect sensor and signal processing that switches in response to differential magnetic signals created by the ferrous gear teeth. The circuitry contains a sophisticated digital circuit to eliminate magnet and system offsets and to achieve true zero-speed operation (manufactured under U.S. Pat. 5,917,320). A-to-D and D-to-A converters are used to adjust the device gain at power on and to allow air-gap independent switching, which greatly reduces vibration sensitivity of the device.

This sensor system is ideal for obtaining transmission and crank information using gear-tooth-based configurations.