Membrane switches use a flexible circuit layer for user input. The membrane typically consists of three layers: a top membrane with conductive traces, a spacer layer, and a bottom membrane with additional conductive traces. When a key is pressed, the top and bottom membranes come into contact, closing the circuit and registering the users’ input.

Elastomer keypads are another type of switch technology, typically made of silicone rubber. These rubber keypads are placed over the membrane layer to provide a tactile feel and response when keys are pressed.