Video subsystem design for EMI control

Low-cost high-speed video controllers and compatible displays are becoming commonplace in the PC and workstation market. The video subsystem is defined as the video controller, analog output path, interconnecting cable, and common CRT-based display. The function and fundamental electromagnetic interference (EMI) design criteria of each are discussed. The interaction of all three makes it difficult to associate video-related EMI problems with one element. Simple models and analysis techniques are discussed to verify performance of each element, while also providing a unique means to positively identify individual EMI sources in a system under test