Also known as Spin-Dependent Tunneling (SDT), Magnetic Tunnel Junction (MTJ), or Tunneling Magnetic Junction (TMJ), Tunneling Magnetoresistance is a spintronic quantum effect that produces a dramatic resistance change in a normally insulating layer, depending on the magnetic field and thus the predominant electron spin in a free layer. The new device has four TMR elements configured as an angle sensor with full quadrature sine and cosine outputs.
The parts come in an ultraminiature 2.5 millimeter by 2.5 millimeter six-pin TDFN package. In typical operation, an external bar or split-pole magnet provides a saturating magnetic field of 30 to 200 Oersteds in the plane of the sensor.
TMR produces a very large signal with no amplification for exceptional precision, wide air-gap tolerance, and low power consumption due to high element resistance. The AAT001-10E is ideal for applications such as rotary encoders, automotive rotary sensors, motor shaft position sensors, and knob position sensors.
Datasheets and more information are available at www.GMRsensors.com or www.nve.com. Available now, AAT001-10E angle sensors are priced at $1.94 each in 1,000-piece quantities. Split-pole ferrite magnets for use with the sensors are available and priced at $1.15 each in 1,000-piece quantities. Customers can also use their own magnets.