Variable reluctance sensors & analog position sensors

Generating magnetic field amplitude variation with variable reluctance

illustration: Variable reluctance sensors & analog position sensors  

MMT has developed a family of position sensors using a variable reluctance to generate the required magnetic amplitude variation. In that case, the permanent magnet and the Hall probe are stationary and the motion of a rotor made of soft magnetic material is detected according to the variation of the airgap. Such variable reluctance sensors have the following characteristics:

  •  Digital or analog output signal according to the choice of the Hall probe
  •  Zero Gauss principal (bi-polar magnetic field variation allow the use of the most standards Hall probes and ASICs)
  •  True Power On sensors
  •  Compatible with automotive requirements
  •  Programmable through the connector (gain, offset, temperature compensation,...)
  •  Specific features for analog design:
  • Minimum mechanical gap up to 3 mm
  • Target profile variation up to 3.5 mm
  • Rotary stroke up to 320°, linear stroke up to 200 mm
  • Possible adaptation of the target profile to customize output signal variation (linear, quadratic, exponential, ...)
  • Non linearity below +/-1% of the stroke on the automotive -40°C to 150°C temperature range
  •  Specific features for digital designs:  
  • Extended mechanical gap operation from 0 to 3.5 mm between Hall probe and one teeth
  • Typical error: +/-0.2° (mainly linked to the target dimensions) 


More information available on demand


MMT also provides rotary sensors, shaft rotary position sensors, multi-turn position sensors and 2D position sensors.


Click on the following pictures to enlarge