AS5040

Data Sheet

www.austriamicrosystems.com

Revision 2.10

26 - 33

18 Angular Output Tolerances

Accuracy

Accuracy is defined as the error between measured angle and actual angle. It is influenced by several factors:

the non-linearity of the analog-digital converters,

internal gain and mismatch errors,

non-linearity due to misalignment of the magnet

degrees @ 25°C (see Figure 25).

Misalignment of the magnet further reduces the accuracy. Figure 24 shows an example of a 3D-graph displaying non-

linearity over XY-misalignment. The center of the square XY-area corresponds to a centered magnet (see dot in the

center of the graph). The X- and Y- axis extends to a misalignment of

±1mm in both directions. The total misalignment

area of the graph covers a square of 2x2 mm (79x79mil) with a step size of 100µm.

For each misalignment step, the measurement as shown in Figure 25 is repeated and the accuracy

Figure 24: Example of Linearity Error over XY Misalignment

-1000

-800

-600

-400

-200

0

200

400

600

800

1000

0

1

2

3

4

5

6

°

x

y

Linearity Error over XY-misalignment [°]

The maximum non-linearity error on this example is better than

±1 degree (inner circle) over a misalignment radius of

~0.7mm. For volume production, the placement tolerance of the IC within the package (

±0.235mm) must also be

taken into account.

The total nonlinearity error over process tolerances, temperature and a misalignment circle radius of 0.25mm is

specified better than

±1.4 degrees.

The magnet used for this measurement was a cylindrical NdFeB (Bomatec® BMN-35H) magnet with 6mm diameter

and 2.5mm in height.