angular position sensor / non-contact / Hall effect / amplified

Model CMI-HX is an angle sensor which is specifically designed to operate under harsh conditions, such as the presence of oil, dust and severe vibrations. It uses innovative patented Hall element technology, with a thin ferromagnetic disk which picks up only the density of the magnetic flux parallel to the the chip surface.

The sensor has a CMOS circuit which comprises two pairs of hall elements, offset cancellation circuit elements, a source of current, and an amplification circuit with chopper stabilization. Each of the two paired Hall elements picks up one of the two directions, X and Y, parallel with the chip surface. The ferromagnetic disk also amplifies the external magnetic field resulting from the shaft movement in a rotary direction, and focuses it on the Hall elements. This ingenious circuit produces a highly stable sensor which is virtually noise-free and yet is exceptionally resistant to aging or high temperatures. This is because the parameter measured is the field direction rather than the strength.