Improved Chip Ferrite Beads Slash EMI, Noise Dramatically

摘要

Filters to screen out electromagnetic interference (EMI) often serve in the periphery of noise sources, such as ICs and interfaces, to decrease noise emissions in electronic equipment. Generally, these kinds of equipment use chip ferrite beads as filters, because they are compact, inexpensive, and easy to install. Their noise-suppression characteristics are stable as well, and beads do not require grounding. In today's market, equipment is diver-sifying and digital equipment is acquiring ever-greater levels of performance. In this environment, device processing speeds are accelerating. These trends are raising the complexity of issues relating to noise-suppression. Engineers are adopting various ways to lower the noise levels in signal lines. In particular, designers must maintain fast rise speeds in waveforms, but this interferes with efforts to lower noise levels.