Patent ID: 7417872

Claim:
A circuit board comprising: a ground plane; a pair of parallel signal paths that run parallel to the ground plane for carrying a digital differential signal, each signal path comprising an upper portion, a lower portion and a central portion electrically coupling the upper and the lower portions throughout their length, the upper and lower portions having a first width dimension and the central portion having a second width dimension that is substantially less than the first width dimension to define an I-shaped cross section of each signal path; and insulating material separating the pair of signal paths and separating the lower portions of the signal paths from the ground plane, wherein the lower, upper and central portions of the parallel signal paths comprise solid conductive material, wherein the width dimensions of the lower, upper and central portions are parallel to the ground plane, wherein the signal paths run length-wise on the insulating material and remain separated by the separation and remain parallel to the ground plane, wherein the signal paths are electrically isolated from the ground plane, and wherein the upper portions are disposed on a surface of the insulating material opposite to the ground plane and the lower portions are disposed completely within the insulating material.