Patent ID: 6278345
Filing Date: 2001-08-21
Classification: H01P,H05K

Abstract:
A flexible printed circuit comprising:a flexible insulative board having a first surface and a second surface opposite to the first surface;at least one conductive transmission line formed on the first surface of the flexible insulative board and the at least one transmission line comprising a plurality of tested sections of a same length, each tested section having an original characteristic impedance, wherein the original characteristic impedances of some tested sections are beyond an acceptable tolerance to a standard value;a compensation region defined at the second surface of the flexible insulative board and separated into a plurality of compensation units having identical area, each compensation unit vertically related to a specific tested section of the at least one transmission line and having a conductive region and a non-conductive region, wherein a specific ratio of the conductive region area to the compensation unit area is determined based on an offset between the original characteristic impedance and the standard value so that the compensation unit can compensate the original characteristic impedance of the tested section of the transmission line opposite the compensation unit and resulting in a final characteristic impedance of the tested section of the at least one transmission line within the acceptable tolerance to the standard value.