Patent attributes
A flexible printed circuit board includes a differential pair arranged in a signal layer and two sheets defined in a ground layer. The two sheets are apart from each other by a void defined in the ground layer opposite to the differential pair. The differential pair includes a number of section pairs, each of which includes two sections arranged in two transmission lines of the differential pair respectively. The differential pair is equivalent to a low pass filter which includes several capacitors and several inductors. Each of the plurality of section pairs can achieve a desired characteristic impedance by adjusting a distance between each section and a corresponding nearest sheet, and a distance between the two sections of each of the plurality of section pairs.
