Patent ID: 7176889

Claim:
A pointing device for integrating into portable electronic devices comprising: a bottom substrate having a top face and a bottom face, the top face including a sensing region comprising a plurality of interdigitated conductive trace regions, each trace region including interdigitated common and sense traces, the bottom substrate defining at least one via through the bottom substrate for each sense trace and the common trace, each via supporting a conductive path from one trace to at least one lead element, the bottom face supporting at least one lead element for each sense trace and the common trace, each lead element solderable to a printed circuit board; a flexible substrate constructed from a heat resistant polymer, the flexible substrate having a resistive layer deposited on a bottom side; a raised pedestal formed on the bottom substrate top face around at least a portion of the sensing region, the pedestal separating the plurality of the interdigitated conductive traces from the flexible substrate resistive layer; a snap dome over the flexible substrate; a keymat membrane covering the snap dome and the flexible substrate, the keymat membrane defining a protruding region surrounding the snap dome; a center keycap positioned on the keymat membrane opposite the snap dome; and a surrounding keycap positioned on the keymat membrane opposite the keymat membrane protruding region; whereby depressing the center keycap collapses the snap dome and brings a portion of the flexible substrate under the snap dome into contact with the bottom substrate sensing region; and whereby depressing the surrounding keycap pushes a portion of the flexible substrate protruding region which in turn pushes a portion of the flexible substrate under the portion of the flexible substrate protruding region into contact with the bottom substrate sensing region.