Crosstalk Analysis of FPC Transmission Line

Flexible printed circuits (FPC) inside mobile products can produce certain electromagnetic interference during signal transmission, which can have a certain impact on product performance. Since different products have different structures and paths of interference propagation, it is difficult to carry out unified optimization to suppress interference in terms of the path. Therefore, this article starts from the FPC line and aims to reduce the electromagnetic interference generated by the FPC line itself, suppressing interference at the source. By applying certain structural adjustments in a simple transmission line, the changes of the S-parameters are simulated and analyzed. After calculating the conversion coefficient from differential mode to common mode, optimization ways are proposed and applied to an actual FPC product model for comparative verification. Finally, by guiding the actual FPC product design through the verification results, this study can play an important role in reducing internal electromagnetic interference in mobile products.