With just one sensor, only the linear region of the curve in Figure 4-10 is usable. This span is ≈140°; therefore, the magnet must be roughly positioned so that the desired measurement range falls within the 140° linear region. The accuracy for this method largely depends on the spacing between the calibration points, and is estimated using Equation 5.

Figure 4-14, Figure 4-15, and Figure 4-16 each show an example of a possible error curve for this setup with a different number of calibration points, calibrated between ±70°.

Figure 4-14 One Sensor Lookup Table Calibrated Error, 7 Cal Points, ≈ 4° Peak-to-Peak Error

Figure 4-16 One Sensor Lookup Table Calibrated Error, 16 Cal Points, ≈ 1° Peak-to-Peak Error

Figure 4-15 One Sensor Lookup Table Calibrated Error, 10 Cal Points, ≈ 2° Peak-to-Peak Error