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AS5055

Datasheet - Application In form atio n

8.2 Placement of the Magnet

Non-Linearity Error over Displacement.

As shown in Figure 18, the recommended horizontal position of the magnet axis is over the diagonal center of the IC.

Figure 17 shows a typical error curve at a vertical magnet distance of 1.0mm, measured with a NdFeB N35H magnet with 6mm diameter and

2.5mm height.

The X- and Y- axis of the graph indicate the lateral displacement of the magnet center with respect to the IC center.

At X = Y = 0, the magnet is perfectly centered over the IC. The total displacement plotted on the graph is for ±1mm in both directions.

The Z-axis displays the worst case INL error over a full turn at each given X-and Y- displacement. The error includes the quantization error of ±½

LSB. At the sample shown in Figure 17, the accuracy for a centered magnet is better than 0.5°. Within a radius of 0.5mm, the accuracy is about

1.0° (spec = 1.41° over temperature).

Figure 17. Integral Non-linearity Over Displacement of the Magnet

-1,0

-0,7

-0,4

-0,1

0,2

0,5

0,8

0

0,5

1

1,5

2

2,5

3

3,5

4

INL [°]

X-displacement [mm]

Y-displacement [mm]

Non-Linearity @ z=1mm

3,5-4

3-3,5

2,5-3

2-2,5

1,5-2

1-1,5

0,5-1

0-0,5