An apparatus comprises a circuit board having a first conductive pad on a circuit board surface and a conductive overlay, which has a first surface and a second surface opposite the first surface and is configured to deflect in response to a touch on the first surface. A protrusion protrudes from the second surface and is configured to be a second conductive pad. The circuit board, the conductive overlay, and the protrusion are arranged such that the second surface faces the circuit board surface and is separated from the first conductive pad by a first distance. The protrusion and the first conductive pad are separated by a second distance and have an overlapping area. The apparatus may also comprise a spacer configured to separate the first conductive pad from the second surface by the first distance and from the protrusion by the second distance.