Knobs are widely used in many scenarios as a way for humans to interact with machines. Detecting the rotation angle of the knob is required in most applications. Compared with traditional knobs, knobs using Hall-effect sensors have more advantages. TI 3D linear Hall-effect sensors such as the TMAG5273 and TMAG5170 can measure magnetic fields in three directions, and can calculate angles in any two axes using the on-board CORDIC calculator allowing the MCU to read the angle directly. In addition, a push-button knob design can provide more versatile functions.