The ADA4571 consists of two dice within one package, an AMR sensor, and a fixed gain (G = 40 nominally) instrumentation amplifier. The ADA4571 delivers clean and amplified cosine and sine output signals related to the angle of a rotating magnetic field. The output voltage range is ratiometric to the supply voltage. Use the part, ADI suggests, for absolute position measurement (linear and angle); brushless dc motor control and positioning; actuator control and positioning; contactless angular measurement and detection; and magnetic angular position sensing.
The sensor contains two Wheatstone bridges, at a relative angle of 45° to one another. A rotating magnetic field in the x-y sensor plane delivers two sinusoidal output signals with the double frequency of the angle (α) between sensor and magnetic field direction. Within a homogeneous field in the x-y plane, the output signals are independent of the physical placement in the z direction (air gap).
The ADA4571 is available in an 8-lead SOIC package.
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