Patent ID: 8068097

Claim:
An apparatus, comprising: a sensing device having a plurality of sensor elements that are electrically coupled to detect a presence of a conductive object on the sensing device, wherein the plurality of sensor elements correspond to a plurality of button operations; a keyboard coupled to the sensing device, wherein the keyboard comprises a plurality of keys that correspond to the plurality of sensor elements; and a processing device coupled to the sensing device to distinguish a particular button operation from among the plurality of button operations when a particular key of the plurality of keys of the keyboard is pressed, wherein the sensing device comprises: a routing layer comprising the plurality of sensor elements, wherein the routing layer is coupled to the processing device; a pad layer comprising conductive material in button areas that corresponds to the plurality of keys and the plurality of sensor elements, wherein each of the button areas is configured to operate as the conductive object that is detected by the routing layer when the particular key is pressed, wherein the processing device is configured to measure capacitances on the plurality of sensor elements to detect the presence of the conductive object when one of the plurality of keys is pressed, and wherein the pad layer does not directly contact the routing layer when the particular key is pressed; and an insulating layer configured to electrically isolate the pad layer and the routing layer when the processing device measures the capacitances, wherein the insulating layer is disposed between the routing layer and the pad layer.