Systematic Design for Mitigation of RF De-sense by Interleaved Power Line in Two-Layer PCB

The RF desense problem in wireless products becomes serious due to faster digital signals and minimal area in print circuit boards (PCBs). This article proposes a systematic design of interleaved power transmission lines to suppress electromagnetic interference due to magnetic coupling from the power delivery system of digital circuits to RF components. It improves noise suppression by more than 20 dB, in only two-layer PCB, with one power trace and three enclosing grounds to replace the conventional power trace in the same occupied area. A general design chart of isolation improvement versus trace width, spacing, and substrate thickness is constructed. Finally, the proposed concept is verified by experiment and simulation.