Course #60
Grounding and Shielding: The Essence of EMC Design
We recommend you to submit your
preliminary or firm registration at least 4 weeks before course
start to ensure a seat on the course.
TECHNOLOGY FOCUS
The discipline of Electromagnetic Compatibility (EMC) is concerned
with the design of Electronic Systems, while minimizing
electromagnetic coupling and interference from within the system
and between systems to their environment.
Meeting the strict EMC standards, as well as ensuring the
satisfactory performance of the equipment in its intended
electromagnetic environment, requires the implementation of
technical measures into the system's design.
Grounding forms an inseparable part of all electronic and
electrical designs, from circuit through system up to installation
design. Grounding is implemented for EMC and ESD protection, for
safety purposes, for lightning and surge protection.
Shielding, on the other hand, is a necessity for avoiding
electromagnetic field coupling from and into equipment enclosure.
Adequate shielding is necessary to enhance immunity of equipment,
and reduce emissions from the equipment enclosure.
Grounding and shielding are two of the essential concepts in EMC
design. No design will be acceptable without them being properly
implemented.
COURSE CONTENT
This is an advanced design course, dealing with the theory and
practices of grounding and shielding for meeting EMC objectives.
The course features understanding of the electromagnetic phenomena
related to electronic equipment and system-level grounding and
shielding.
The course covers the grounding and its topologies, leading to the
implementation of grounding from circuit to system. With respect to
shielding, the course will cover issues such as the shielding
properties of metals, and the compromises in shielding, which are
the main objective of shield design.
Case studies and practical "real life" examples will be
provided.
Monday
Fundamental Concepts
- Basic concepts of EMI phenomena and EMC and the primary
parameters that govern interference modes and system performance
with respect to EMC
- A video presentation, "EMI: The Silent Threat"
Signals and Coupling Modes
- Characteristics of signals, in particular their spectral
content
- Concepts of common-mode vs. differential-mode signals,
particularly
with their effect of EMI interactions
- Fundamental field concepts, with special emphasis on magnetic
field interactions
- Manner of signal propagation in circuits and systems
- Concept whereby current follows the "path of least impedance"
and the implications of this concept
- Transmission line fundamentals and frequency
considerations
Circuit Elements
- Characteristics of real world circuit elements, with special
emphasis on parasitic inductance, capacitance and resistance
Fundamentals of Grounding Design
- Concept of grounding, and basics of grounding system
designs
- Reasons and rationale for grounding and conflicts between
grounding
and other system requirements (e.g., safety considerations)
Grounding Essentials
- Fundamental grounding topologies
- Structured methodology for the design of the grounding
tree
Tuesday
Ground-Loop Interaction and Coupling
(GLIC)
- Concepts (and myths) associated with "ground loops"
- Common to differential mode conversion phenomenon, consequent
of ground loops
- Mitigation techniques of ground loop generated interference
such as isolation transformer, Baluns, optocouplers, and other
Equipment and System-Level Grounding
- Dilemma associated with interconnects between large scale
systems and installations
- Application of the fundamental grounding theory to different
tiers of equipment and systems
- Interconnection of multiple ground connections
Implementation of Grounding on Printed Circuit
Boards
- Objectives of grounding on PCBs, including those of signal
current
return and signal reference
- Implementation of grounding for each of the objectives
- Concepts of power distribution and transmission line signal
propagation on PCBs and the role of the grounding system in their
implementation
- Mixed analog/digital circuits and approaches for grounding to
be applied, particularly when analog-to-digital (A/D) and
digital-to-analog (D/A) converters are incorporated in the
circuit
- Special considerations of grounding in PCBs, including moats
and ground fills and chassis stitching
Wednesday
Cable Shielding and Shield Termination
- Basics of field to cable interaction and one of the solutions,
in the form of cable shielding
- "How should the cable shield be grounded, at one or both
ends?"
- A comparison of signal circuit wiring grounding vs. shield
grounding, and the fundamental difference between the two
Bonding
- Manner of achieving high-quality electrical connection
- Bonding as a link between grounding and shielding, and
techniques for achieving acceptable bonds
- Dissimilar metals and metal electrochemical compatibility
between bonded structures
- Manner for corrosion control
Fundamental Shielding Theory
- Fundamentals of equipment shielding and mechanisms contributing
to the shielding effectiveness of an enclosure
- Significance, limitations and the factors contributing to
reflection and absorption
mechanisms
- Unique approaches to shielding against low-frequency magnetic
fields
Thursday
Shield Discontinuities and Their
Treatment
- Effects of discontinuities in shielding materials, and
solutions to aperture and slot leakage
- EMI gaskets and their application
Equipment and System Shielding Design
- Implementation of shielding to equipment external and internal
(partitioning) shielding
- Application of shielding at the equipment rack and console
levels
- Implementation of shielding on the PCBs ("shield cans")
Shield Integrity Violations
- Manners of undesirable (yet common) violations of the shielding
integrity, including shield penetrations and discontinuities
- Manners and materials available for preclusion of such
violations
Grounding and Shielding Related Case
Studies
- Real-life grounding and shielding case studies
- The participants will also be encouraged to share their own
case studies at this time.

Said about the course from previous participants:
"The course had many references to real life cases and
problems."
"I liked that all the aspects of different topics were explained
in detail."
"It covers a lot of aspects of EMC."