Analysis on the effectiveness of the 20-H rule using numerical simulation technique

摘要

With increasing demand for higher operating frequencies, printed circuit board (PCB) designers are faced with numerous obstacles during the design cycle. The 20-H rule is one layout technique that is recommended to minimize radiated fields propagating from the edges of a PCB. These fields, either magnetic or electric, may corrupt adjacent cable assemblies, sheet metal enclosures and aperture openings. The magnitude of this design rule is investigated herein using the numerical electromagnetic simulation method, Finite Difference Time Domain (FDTD). In addition, an analysis on whether benefits exist from use of the 20-H rule is examined. The significance to the field of EMC lies in presenting, for the first time, an exhaustive analysis that took over one year to achieve using various configurations and frequencies. A rigorous analysis indicates that benefits do occur from use of the 20-H rule, but only when implemented in certain applications.