AS5043

Data Sheet – Choosing the Proper Magnet

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Revision 1.80

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15 Choosing the Proper Magnet

Typically the magnet should be 6mm in diameter and ≥2.5mm in height. Magnetic materials such as rare earth AlNiCo,

SmCo5 or NdFeB are recommended.

The magnet’s field strength perpendicular to the die surface should be verified using a gauss-meter. The magnetic field

(see Figure 18).

Figure 18: Typical Magnet and Magnetic Field Distribution

N

S

Magnet axis

Vertical field

component

(45…75mT)

0

360

360

Bv

Vertical field

component

R1 concentric circle;

radius 1.1mm

R1

Magnet axis

typ. 6mm diameter

S

N

15.1 Physical Placement of the Magnet

The best linearity can be achieved by placing the center of the magnet exactly over the defined center of the IC package

as shown in Figure 19.

Figure 19: Defined IC Center and Magnet Displacement Radius

1

Defined

center

2.433 mm

2.433 mm

3.9 mm

3.9 mm

Area of recommended maximum

magnet misalignment