Displacement and angle sensors

Because of their precision and robustness, potentiometer displacement and angle sensors in polymer thick-film technology are the most commonly-used solutions for displacement and angle measurements.

With potentiometric sensors the “only” thing that needs to be mastered is the interaction between the dynamic sliders and the conductive polymer layer; a passive sensor is then used that has an extremely simple design with the following characteristics:

  • 3% linearity, up to 0.1% attainable  
  • Only two components are necessary for the signal transformation: potentiometer screen-printed on the circuit board and collector track and slider  
  • Signal amplification 1, which means output signal 0 – 100% without amplifier  
  • Passive system without EMC problems  
  • Ratiometric system mostly independent of supply voltage  
  • Temperature coefficient of the output signals (voltage divider < 15 ppm/K)  
  • With the appropriate substrate material, ambient temperatures of up to 180°C permitted  
  • With the right tribologic pairing of slider-polymer layer as a kind of wear-free gliding partner  

With potentiometers and switches in polymer thick-film technology, the needs and demands on associated sliding contacts constantly increase. Würth Elektronik FLATcomp Systems offers a standard slider for this reason. Combined with the WE potentiometer, it lasts longer than two million cycles.

Examples of practical application

  • Height sensor (clearance between wheel and chassis)  
  • Position sensor for exhaust return valve