ADA4571-2 Anisotropic Magneto Resistive Sensor

ADI's ADA4571-2 is a 2-channel anisotropic magneto resistive (AMR) sensor with integrated signal conditioning amplifiers and analog-to-digital (ADC) drivers. The device produces analog outputs that indicate the angular position of the surrounding magnetic field. Each channel consists of two die within one package: an AMR sensor and a variable gain instrumentation amplifier. The ADA4571-2 delivers clean and amplified cosine and sine output signals per channel related to the angle of a rotating magnetic field. The output voltage range is ratiometric to the supply voltage. Each sensing channel contains two separated Wheatstone bridges at a relative angle of 45° to one another. A rotating magnetic field parallel to the plane of the IC package delivers two sinusoidal output signals, with the double frequency of the angle, α, between the sensor and the magnetic field direction. Within a homogeneous field parallel to the plane of the IC package, the output signals are independent of airgap between the sensor and the magnet.

The evaluation board (EVAL-ADA4571-2) features an on-board 5 V regulator, a 6-channel simultaneous sampling ADC, and jumpers to enable temperature compensation and power-down modes within the ADA4571-2. The motherboard also features test points and unpopulated coaxial connectors for the six outputs of the device. The EVAL-ADA4571-2 mounts the ADA4571-2 in an end-of-shaft magnet configuration. The evaluation kit is composed of an ADA4571-2 motherboard, a magnetic stimulus on a hand-turnable mount, a USB interface, and an SDP-S controller board.