In one embodiment, an apparatus includes a housing with a conductive surface. A circuit board may be positioned within the housing. The circuit board includes a deflectable portion that may be movable relative to the housing. A conductive pad is positioned on the deflectable portion of the circuit board. A spring member is positioned between the housing and the circuit board. The spring member may be movable between a first configuration and a second configuration. The conductive pad of the circuit board may be spaced away from the conductive surface of the housing by the spring member in the first configuration and in contact with the conductive surface of the housing with the spring member in the second configuration.