emc

Filter connectors are often a misunderstood product for many components engineers. The lack of understanding is often a result of the fact that filter connectors seldom make the “What’s New” headlines and because many engineers typically don’t have a need for them. But those who do are certainly glad they are available!

“I’ve all ready read the books on EMC and visited a lot of home pages... But all these references did not mention anything about the physical phenomenon that causes common mode currents... Are common mode emissions inherent in any physical system? Can I model them?” Overheard on the ‘Net

It’s by no means a trivial question. And, in spite of decades of hand waving by authors and consultants, the principal mechanism by which common mode currents are created in digital devices was not well understood until the decade of the 90s. In this article, we’ll explore the physics behind the creation of common mode currents, and perform some experiments to verify our understanding.

When a manufacturer is thinking of the European Union (EU) as the next market for its electronic equipment, EMC compliance is one of the must-haves on the list of approvals. Unless a company has dedicated quality personnel to ensure testing and certification is done to the letter, the approval process can be quite complicated for engineers – from identifying the correct standards and models for testing to writing the declaration of conformity and preparing the product for testing. This article will explain what engineers need to do to demonstrate compliance.