Position sensors achieve high accuracy measurement

The contactless sensors precisely measure linear displacement, movements, torque and velocities in dirty and harsh environments typical found in vehicle, engine, automation and general industrial applications. A high operating temperature of +150°C, and small dimensions of 2x6x0.75mm, further opens the range of use for these compact, precision position sensors. The use of pole wheels allow for highly accurate angular measurements on the shaft circumference, easily achieving resolutions better than 0.001° (19-bit).

The sensors’ small wall thickness allows for large air gaps - up to half of the sensor’s respective pole pitch - that won’t affect performance, since signal amplitudes only depend on the magnetic field direction and are nearly independent of the magnetic field strength. Both incremental and absolute position detection is possible with the non-contact, anisotropic magneto-resistive measurement principle of the sensors. Because the KMXP sensors detect a magnetic field gradient, they are virtually insensitive to homogenous stray fields and vibrations. This contributes to the high accuracy measurement by allowing for increased resolution at high speeds, up to several meters per second.

The output of the sensors is sine/cosine with 10mV/V. In combination with an interpolator device and magnetic scales, measurement ranges from µm to km are possible with high precision. Current models of the linear position sensor series are the 2mm pole pitch KMXP2000 and 5mm pole pitch KMXP5000, with a 1mm pole pitch version scheduled for later this year. All are pin-compatible and employ a common PCB layout to simplify design. The KMXP series is REACH, 3TG and RoHS-compliant.