Course Description

Shielding and grounding are the two basic concepts upon which EMC design is built. Both shielding and grounding will be explained from fundamental principles through traditional design methodologies. While usually considered separately, these two areas are tied together, and ignoring this can result in poor EMC performance. Finally, more advanced concepts are presented to help those involved in leading edge design develop their expertise.

Who Should Attend?

This seminar is provided to support those involved in all areas of EMI design and compliance testing. Anyone who needs a basic understanding of these EMC essentials will benefit from this seminar. In addition to those directly working with EMC, hardware design engineers and managers will find that this seminar provides a good base on these important topics.

Benefits of Attending

Those attending will leave with a clear understanding of shielding and grounding, from basic to advance concepts. This will allow hardware and EMC engineers to work together more closely, and with less confusion.

Outline

• Introduction to Shielding

What is shielding and how does it work? In the first presentation the basic physics behind shielding will be explored. A qualitative approach to understanding shielding and the effect of apertures and seams will be given. Imperfect shields have a great deal in common with poor antennas; this behavior explains a lot of misunderstood measurements during EMC testing.

• Shield Design

Shielding effectiveness calculations form the basis of shield design. The equations apply to a set of well-defined conditions and include the effect of apertures. A series of well-known corrections are also provided that can significantly expand the range of cases for which these equations can be used.

• Real Shield Behavior

In this presentation the complexities of shield performance in real products is discussed. There are a number of factors that are not considered in the formulae that form the basis of the traditional shielding calculations. Although these equations provide a good start, there are subtleties that must be controlled either by avoiding the situation or by more detail calculations, usually employing computational electromagnetic techniques.

• Introduction to Grounding

Grounding is one of the most misunderstood and abused terms in the EMC world. The reason for this is historic, and relates back to the use of real earth ground as a signal return. Unfortunately the general understanding of the word has not kept pace with technology. As a result we have safety grounds and grounds for shielded cables that are very different things.

• References and Returns

The EMC reason for grounding can be split into a number of quite different functions. Grounding is used to provide return paths for signals, to provide a return for circuit power, and to act as a reference point for interfaces between devices. To add to the confusion a single set of ground conductors may be used for one or more of these purposes. Each grounding function will be clearly explained, helping the designer to produce a grounding strategy appropriate for the product being designed.

• Grounding Schemes

There are a number of fundamental grounding schemes, single point and multi-point being the best known. Each of these was developed for a specific purpose and they provide a starting point for the EMC design. This aspect of grounding can tie very closely to the shielding of a product, and designing one of these without regard to the other can produce very poor EMC performance. The synergy between shielding and grounding will be examined.

Speaker Bio

Colin is a staff engineer for the Southwest Research Institute (SwRI) in the Electromagnetic Compatibility Research and Testing group. In this position Colin’s responsibilities include developing new EMC technologies, providing consulting services, participating in internal and external research programs and collaborating with the EMC community at large. Prior to SwRI, Colin spent 22 years at HP (Compaq/Digital).

Colin has been active in the area of antenna and shielding behavior since the early 1970’s. He has authored over 20 technical papers and articles and holds eleven patents for various methods of EMI control; others are in process. Colin is a co-author of the book, EMI/EMC Computational Modeling Handbook (Kluwer Academic, 2nd Edition 2001), and in 2002 Colin received the IEEE EMC Society Certificate of Technical Achievement for his contributions to the development of EMC models directed to understanding EMI shielding and antenna behavior.

In addition to his technical papers, Colin has presented numerous workshop sessions and training classes on EMC and signal integrity. These embrace a broad range of topics ranging from microprocessor packaging, through printed circuit module issues, to system design and shielding. In many of these classes, explanations are clarified with a combination of simulations and data from measurements. He is a NARTE certified EMC Engineer, a member of the dB Society, a senior member of the IEEE EMC Society, and is serving his second term on the society’s board of directors. He is vice chairman of the IEEE EMCS Standards Development Committee and active in the IEEE EMCS TC-9 and ANSI accredited C63 committees. Colin also served a term as a Distinguished Lecturer for the IEEE EMC Society in 2001 and 2002.

Decision (Run/Cancel) Date for  this Course is Monday, May 12, 2008

Course Fee Schedule:

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Updated Monday March 03, 2008