Adafruit Circular Soft Potentiometer (Ribbon Sensor)

Manufactured by Spectra Symbol, these ribbon controllers, also known as 'soft potentiometers', feature a unique circular design with a donut-shaped sensing area. The outer diameter measures 55.96mm (2.2 inches) and the inner diameter is 35.63mm (1.4 inches).

With a nominal 10K resistance across the two outer leads, the resistance of the middle pin varies depending on the pressure point along the strip. When untouched, the middle pin floats; ensure you use a weak pullup like 100K ohm.

To operate, connect one side pin to ground via a 10K resistor and the other side pin to your Vcc power line via a different 10K resistor. The middle pin's analog voltage will range from 1/3 Vcc to 2/3 Vcc. Avoid direct ground and power connections to ensure optimal functionality.