The end goal is to map the device output to a distinct mechanical position. As our magnet contained in the moving body is not confined to a single straight path, but rather a rotation, yawing, tilting, or pitching within one or more planes, at least 2 Hall-Elements are needed to avoid spatial aliasing as indicated in Figure 2-3. Figure 2-4 illustrates that with data from perpendicular sensing elements, both a unique joystick pitch value and unique rotation value can be extracted from 2 sensors that by themselves can not distinguish joystick position.

Figure 2-3 Aliasing

Figure 2-4 2 Sensor Pitch and Rotation Extraction

Figure 2-5 shows a single device design that utilizes a 3D sensor like the TMAG5273, which has hall elements sensing along the x and y axis, or the TMAG3001 for space constrained applications. For this design, strive to place the device such that you obtain an output similar to Figure 2-6. As the joystick shaft is moved in a circular path for a given pitch, the x-axis and y-axis fields exhibit a sinusoidal behavior relative to the sensor.

Figure 2-5 1 Device Design

Figure 2-6 1 Device Example Plots

Figure 2-7 shows a two device design that utilizes 2 Hall-Elements sensing along the z-axis with output behavior as indicated in Figure 2-8. For the two device design, an analog output device can be used like the TMAG5253 or if there is not an available ADC, a digital design like the TMAG5273 or TMAG3001 can be used.

Figure 2-7 2 Device Design

Figure 2-8 2 Sensor Design Goal