Stepper Motors
	Providing accurate positioning in a flat package at very low cost
	MMT stepper motors are characterized by their ability to provide a smooth and accurate motion at very low cost. It is the result of several years of design and optimization by specialists of permanent magnet contactless structures. MMT engineers have created the most simple – and reliable – architecture that can be imagined for an electromagnetic rotary device, and have integrated it in a slim shape, which is really easy to adapt in your application. The main features of this family of motors are:
						Exploded view of a MMT 2-phase stepper motor for instrument clusters
	· A slim shape with an integrated gear reducer · Available in 2 or 3 phases versions · All phases mounted in the same stack of laminations · The residual detent torque can be set according to the application specifications · Disc or ring designs · Scalable size & torque design
	MMT 2-phase stepper motor basic principle MMT disc design (available in 2 or 3 phases)
		This solution is typically adapted to high volume and low cost production. Indeed, each part can be fabricated either by molding or stamping and is especially designed for a simple and efficient assembly. We obtain a low cost structure with extremely high life duration and low torque ripple.
	Basic Principle
	Let us consider the 2-phase motor shown here above in a given position 1 when coil A is supplied with a positive current. A north pole is created at the extremity of the tooth which attracts a south pole of the magnet. A transition of the multipolar magnet is then in front of the other phase. When coil B is supplied, a north pole is created at the extremity of its main tooth and the magnet rotates by 18° (for a 5-pole pair magnet) to align with the field as illustrated in 2. In the next step, coil A is supplied with a negative current, which creates a south pole and a north pole of the magnet is attracted in front of that tooth (3). By setting the appropriate current values, we will easily be able to drive this motor. Half-stepping or microstepping can also be achieved by using standard drivers.
	Main applications
	MMT stepper motors are particularly well suited for high volume, low cost positioning applications at low input power. They are ideal for automotive applications because of their small and flat package, and their low weight. They have been mainly used for positioning applications, such as dashboard actuators or climate control valves. MMT steppers and brushless motors can be used in a variety of applications:				Carburator flap actuator
	2-phase stepper motor for dashboard applications	·Head lights leveling ·Mirror positioning ·Drivers for multimedia applications ·Tachograph ·Climate control flap actuator ·Carburator flap actuator
	Climate control applications			Dash board applications
					Patents for these technologies are granted or pending in USA, Europe, Korea and Japan.
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