EMI: Why Devices Radiate (original) (raw)

Abstract

Many of the problems associated with emissions from electronic equipment can be explained using the concept of “lost flux.” Any circuit will produce magnetic flux. However some of this flux does not remain confined to the circuit but instead envelopes it. This lost flux creates a common mode voltage across the circuit causing attached conductors to radiate. In this article we explore the concept of lost flux and through a series of experiments, demonstrate how it is possible to design circuits to minimize unwanted radiation.

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References (8)

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  8. Glen Dash is the author of numerous papers on electromagnetics. He was educated at MIT and was the founder of several companies dedicated to helping companies achieve regulatory compliance. Currently he operates the Glen Dash Foundation which uses ground penetrating radar to map archaeological sites, principally in Egypt. Copyright Ampyx LLC