Patent ID: 7978175

Claim:
An input device, comprising: a moveable upper magnet having an upper surface and a lower surface; an electrically conductive member disposed below the lower surface of the upper magnet and moveable in conjunction therewith; an electrode array comprising a plurality of electrically conductive sense electrodes and at least one drive electrode, the sense and drive electrodes being spaced apart from the electrically conductive member by a gap; a stationary lower magnet disposed below the plurality of sense electrodes and the drive electrode, the lower magnet being configured and positioned to attract the upper magnet to a centered rest position thereabove; a drive signal circuit configured to provide an electrical drive signal to the electrically conductive member through the drive electrode and the gap, and a capacitance measurement circuit operably coupled to the electrically conductive member and the sense electrodes, the circuit being configured to detect changes in capacitance occurring between the electrically conductive member and the sense electrodes when the upper magnet is moved from the centered rest position; wherein the upper magnet is moveable by a user in respect of the lower magnet, the plurality of sense electrodes and the drive electrode disposed therebelow, and the lower magnet is further configured to exert a magnetic force on the upper magnet to return the upper magnet to the centered rest position when the upper magnet is moved from the centered rest position and then released by the user.