Touch Springs Using springs to build capacitive sensors Electro-capacitive sensing is a robust alternative to traditional mechanical switches. However, there are applications where the printed circuit board cannot be placed directly under the overlay, nor can the printed circuit board be attached to the device enclosure.

Such applications include household appliances such as stoves, washing machines, refrigerators, microwave ovens, and various vehicle electronics such as radios, TV tuners, control panels, and in-seat occupant detection systems.

Different shapes of springs can be used in practical applications. Each shape has its pros and cons. Common springs include circular springs, variable diameter circular springs, and rectangular springs.