Rotary Position Sensors
Providing a highly linear output signal versus rotary position using a contactless principle
MMT rotary position sensors are based on the use of a permanent magnet and Hall effect sensors. The principle is completely contactless which ensures a life duration of several millions of cycles and the possibility to operate at rather high frequencies and in the most severe environments. The main features of this family of sensors are:
							Integration of 2-pole ring magnet rotary position sensor
· Contactless principle · Very high linearity of the output signal (error below ±0.5%) on a –40 to +150°C temperature range · Low sensitivity to production tolerances and background magnetic fields · Programmable through the connector (gain, offset) after assembling
Basic structure for an outer ring magnet rotary position sensor
				The useful sensing stroke may be as large as 150°. Moreover, some solutions have been developed to provide multi-turn sensing. Several structures, either with disc or ring magnet, are available. The adaptation of our sensors to your needs also includes the choice of the Hall probe according to your specifications.
Basic Principle
Position 1	Position 2
Flux line in MARPS
The basic working principle is explained above : a 2-pole ring magnet is glued on a magnetic yoke and is free to rotate within two stators between which a Hall probe is located. When the magnet transition is horizontal (position 1), no flux is flowing through the slot and the output signal is equal to the selected offset. When the rotor rotates, the flux in the air gap increases as a linear function of the rotary position to provide the typical characteristic shown in the measurement graph.
Main applications
MMT rotary position sensors are particularly well suited for applications requiring highly linear sensing devices that can withstand millions of cycles in a demanding environment (dust, vibrations, etc…). Moreover, their low manufacturing cost and the possibility to program the main useful parameters after assembling offers a very efficient and reliable solution for high volume production. The main applications for MMT rotary position sensors are:
Suspension position sensors		·Throttle position sensors ·EGR valves, pedal position sensors ·Suspension position sensors ·Hydraulic servo valves position sensors ·Steering column sensors ·Torque sensors ·Windshield wiper position sensors				Throttle body position sensor
Rotary EGR valve position sensor			Pedal position sensor			Patents for these technologies are granted or pending in USA, Europe, Korea and Japan.
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