Issue link: https://iconnect007.uberflip.com/i/1535183
Beyond Design Feature Column by Barry Olney, IN-CIRCUIT DESIGN PTY LTD / AUSTRALIA 64 DESIGN007 MAGAZINE I MAY 2025 Radiation and Interference Coupling Radiation and interference coupling pose significant challenges to the performance and reliability of high-speed digital designs. Whether it's the unintended emission of electromagnetic waves or the interaction of signals between adjacent circuits, these phe- nomena can lead to unwanted noise, signal distortion, and even system malfunctions. Understanding the mechanisms behind radia- tion and interference coupling is crucial for electronics designers seeking to design robust and efficient systems. e characteristic impedance of a transmis- sion line is determined by its conductor geom- etry, and it represents the ratio of the electric field (E) intensity to the magnetic field (H) intensity as they propagate along the line. On PCBs, the proximity of traces to each other Figure 1: Electromagnetic fields of traces on a multilayer PCB.