Touchpad with a double-layer printed circuit board structure

A touchpad with a double-layer printed circuit board structure comprising:

• an upper layer;
• a bottom layer;
• a plurality of first conductors between the upper layer and the bottom layer;
• and
• a plurality of second conductors between the upper layer and the bottom layer;
• wherein
• the upper layer of the printed circuit board is configured to act as a touch-sensitive zone, and comprises a plurality of first conductive units along a first axis, a plurality of first conductive wires along the first axis and a plurality of second conductive units along a second axis;
• the bottom layer of the printed circuit board comprises a wire connecting zone and a component zone defined by the wire connecting zone, wherein the wire connecting zone further includes a plurality of second conductive wires along the second axis;
• and
• wherein
• the plurality of first conductive units are serially-connected via the plurality of first conductive wires to form a first touch-sensitive line, wherein the first touch-sensitive line is configured to be electrically connected to the component zone via the plurality of first conductors between the upper layer and the bottom layer and a plurality of first wires between the plurality of first conductors and the component zone;
• and
• the plurality of second conductive units are serially-connected via the plurality of second conductive wires in the bottom layer and the plurality of second conductors between the upper layer and the bottom layer to form a second touch-sensitive line, wherein the second touch-sensitive line is configured to be electrically connected to the component zone via a plurality of second wires between the plurality of second conductors and the component zone.