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AS5215

Datasheet - Detailed Descr i pti on

Figure 11. Magnetic Field Lines with Spacer Between Magnet and Iron Shaft

If the magnet has to be mounted inside a magnetic shaft, a possible solution is to place a non-magnetic spacer between shaft and magnet, as

shown in Figure 11. While the magnetic field is rather distorted towards the shaft, there are still adequate field lines available towards the sensor

IC. The distortion remains reasonably low.

7.1.6 Summary

Small diameter magnets (<6mm Ø) have a shorter linear range and allow less lateral misalignment. The steeper slope allows larger axial

distances.

Large diameter magnets (>6 mm Ø) have a wider linear range and allow a wider lateral misalignment. The flatter slope requires shorter axial

distances.

The linear range decreases with airgap; Best performance is achieved at shorter airgaps.

The ideal vertical distance range can be determined by using magnetic range indicators provided by the encoder ICs. These indicators are

named MagInc, MagDec, MagRngn, or similar, depending on product.