1 Introduction

This ROTATEPUSH-MAG-ACC attachment uses an N42 grade cylindrical magnet as a magnetic field source to demonstrate the ability of magnetic sensors to track rotational and push button motion of a nearby magnet. The magnet is glued into a 3D-printed knob object, which can rotate freely about the 3D-printed base. The knob can also be pressed and return back to the starting position due to the spring. More details about this function are described in Using Hall-Effect Sensors for Contactless Rotary Encoding and Knob Applications and 3D Hall-Effect Sensor for Knobs in Appliances.

Examples of expected magnetic field data captured using the TMAG5173EVM are shown in Figure 1-1.

Figure 1-1 Example Rotation Output with On-Axis Alignment

Nylon components were selected as these components are non-magnetic and do not interfere with the magnetic field and bond well when glued.

Figure 1-2 ROTATEPUSH-MAG-ACC Attachment

This function can be further explored using the angle encoding reference design in the TI Magnetic Sense Simulator tool (TIMSS) available at https://webench.ti.com/timss/.

Figure 1-3 TIMSS Angle Encoding Reference Design