Mechanical Topics (Shielding of Enclosures and Cables) for EMC



Overview

This course is intended for both mechanical and electrical engineers and provides clear applications, theory and demonstrations for the successful design of mechanical enclosures and shielded cable assemblies for good system emissions and immunity performance. Key topics include grounding at the PCB and enclosure, system ground maps, PCB component placement and control drawings, selection of metal type for low versus high frequency shielding, enclosure and cable shielding, PCB device “cans”, resonant slots and enclosures, heat sinks, unintentional antennas, as well as connector, screw and conductive gasket placement. 

This course is Day 1 (PM only), Day 2 and Day 5 of a week-long programme:

At checkout, you may choose to add either or both of Day 3 and Day 4 to your enrolment.

Programme details

Day 1 - Monday 13 April, 1:00pm - 5:30pm

Section 1: Measuring and Inducing noise

  • The electrical noise model
  • Distinguishing the four noise paths by name, electrical driving function, necessary physical features, and impact of source to victim distance
  • Troubleshooting techniques based on the noise model
  • Far-field versus Near-field coupling + DEMONSTRATION
  • Practical antenna theory for radiated emissions and immunity + DEMONSTRATION
  • Conducted emissions—mode separation, LISNs, troubleshooting
  • Practical applications

Day 2 - Tuesday 14 April, 9:00am - 5:30pm

Section 2: Understanding the Physics and Root Causes of Noise Problems

  • Capacitance—in ESD, PC boards, decoupling networks, filter networks, cables + DEMONSTRATION
  • Electrostatic discharge (ESD). IC and system ESD tests. Problems with test repeatability. Design techniques to improve PCB ESD immunity + DEMONSTRATION
  • Inductance—in PC boards, connectors, ICs, high speed signal paths, decoupling networks
  • How to use connectors for improved signal quality, reduced emissions and improved immunity
  • Behaviour of current paths at low and high frequencies + DEMONSTRATION

Day 5 - Friday 17 April, 9:00am - 5:30pm

Section 3: Enclosure Shielding Issues 

  • Typical unintentional (accidental) antenna models 
  • Near-field versus far-field coupling 
  • CASE HISTORY of client 12.5 GHz radiated emissions problem 
  • CASE HISTORY of client 100 MHz radiated emissions and near-field coupling problem 
  • Prevention of “accidental antennas” 

Section 4: “Ground” and Ground Maps 

  • Signal return versus ground 
  • Why, how to, and where to make connections to a conductive enclosure 
  • How to visualize the path of noise current 
  • What to ground, where, and why 
  • Connections to shielded power filters and shielded connectors 
  • Effects of heat sinks 
  • “Ground” / reference maps 
  • External shielded connector interfaces 

Sections 5: Shielding of Conductive Enclosures

  • How does electromagnetic energy enter and exit a conductive enclosure? 
  • Confusing grounding with shielding 
  • Classical shielding and shielding for EMC 
  • Problems with the prediction of shielding effectiveness 
  • Conductivity, holes, slots, seams, choice of metal. 
  • Slot and cavity resonances in shielded enclosures + DEMONSTRATION 
  • Discussion of research math that describes shielding performance and enclosure holes 
  • Review: The three properties of electromagnetic shields 
  • Reflective and absorptive properties of shields + low frequency shielding + DEMONSTRATION 
  • Magnetically conductive materials + APPLICATION 
  • Transfer impedance for base materials, connectors, cables and enclosures 
  • Simple tests to verify performance of enclosures and transfer impedance + DEMONSTRATION 
  • Overall shielding using enclosures 
  • How to make a GOOD or BAD seam + 2 CASE HISTORIES 
  • How to visualize and measure performance of conductive gaskets 
  • PCB level shields + factors that affect performance 
  • Troubleshooting techniques 

Section 6: Shielding of Cables and Connectors 

  • Cable shielding and terminations at low and high frequencies 
  • Applying transfer impedance concepts to cables, connectors, and system interconnect 
  • Examples and discussions of common shielded connectors and their defects (ENET, d-sub, video) 
  • Shield terminations + DEMONSTRATION 
  • Examples 2 CASE HISTORIES of bad cable shielding designs 
  • How to identify good and bad shielded connectors + 2 APPLICATIONS  
  • Test your knowledge by reviewing a proposed design 

Appendix: Bonus Content 

  • Types of Shields 
  • Twisted Pair Wires 
  • Conductive Gaskets 
  • Galvanic Series 
  • “Honeycomb” vent filters 

Test and measurement equipment for this course is supplied by Rohde & Schwarz 

Attending Your Course 

Further details will be emailed to you two weeks ahead of your course, which will include registration information. 

Please get in touch if you have not received this information within five working days of the course start date.  

In the meantime, you may wish to plan your travel: Travel information 

 

Certification

In order to be eligible for a certificate of attendance, you will need to attend the whole course. Participants who meet this criterion will be emailed after the end of the course with a link, and instructions on how to access their University of Oxford digital certificate.

The certificate will show your name, the course title and the dates of the course you attended. You will be able to download your certificate, as well as share it on social media if you choose to do so.

Fees

Description Costs
Days 1 (PM only), 2 and 5 (standard course fee) £1260.00
Day 3 - Applying Practical EMI Design (optional) £625.00
Day 4 - Advanced PCB Design (optional) £625.00

Payment

Fees include course materials, tuition, refreshments, and lunches on Tuesday and Friday. The price does not include accommodation.

All courses are VAT exempt.

Register immediately online 

Click the 'Book now' button on this webpage. Payment by credit or debit card is required.

Request an invoice

If you require an invoice for your company or personal records, please complete an online application form. The Course Administrator will then email you an invoice. Payment is accepted online, by credit/debit card, or by bank transfer.

Tutor

Lee Hill

SILENT Solutions LLC & GmbH, USA & Germany

Lee Hill is Founding Partner of SILENT, an independent EMC and RF design firm established in 1992 that specializes in EMC and RF design, troubleshooting and training. 

Lee received his MSEE from the Missouri University of Science & Technology EMC Laboratory, emclab.mst.edu.

He teaches a graduate course in EMC as a member of adjunct faculty at Worcester Polytechnic Institute (WPI), and is also an EMC course instructor for Texas Instruments, the University of Oxford and the IEEE EMC Society’s Global University, which he currently chairs. He is a past EMC instructor for UC Berkeley, Agilent and Hewlett Packard.

With over 30 years of EMC design and troubleshooting experience, Lee consults and teaches world-wide, and has presented courses in Taiwan, China, Poland, Singapore, Mexico, Norway, Canada, South Korea, France, Germany and the United Kingdom. 

Lee is a past member of the IEEE EMC Society's Board of Directors (2004-2007).

Learning outcomes

After attending this course you will be able to:

  • Effortlessly identify unintentional antennas using pictures of past SILENT projects with EMI problems
  • Easily and simply visualise common-mode current in cables and enclosures
  • Explain the four noise coupling paths and identify near-field coupling in real designs
  • Understand the function of grounds in electronic product design
  • Understand shielding of enclosures and cables, without electromagnetics mathematics
  • Design a "good enough" high frequency shield
  • Design a "good enough" low frequency shield
  • Identify the most common types of grounding and shielding defects
  • Apply the concepts of conductivity, transfer impedance and skin depth to practical designs
  • Estimate the resonant frequencies of enclosures, slots and waveguides
  • Specify shielded connectors and cable assemblies to ensure good system EMC

Application

If you would like to discuss your application or any part of the application process before applying, please click on 'Ask a question' at the top of this page.

Level and demands

This course is intended for mechanical and electrical engineers responsible for the mechanical design and packaging of electronic products, cables and systems. But it is also appropriate for Digital Logic Designers, Analogue Designers, Technicians, EMC Specialists and Applications Engineers. Anyone working with electronic circuits along with conductive enclosures, shielded and unshielded cables who is concerned the control of low and high frequency electrical noise in electronic systems in order to meet functional and regulatory EMI / EMC specifications will enjoy this course.

Accommodation

Although not included in the course fee, accommodation may be available at our on-site Rewley House Residential Centre. All bedrooms are en suite and decorated to a high standard, and come with tea- and coffee-making facilities, free Wi-Fi access and Freeview TV. Guests can take advantage of the excellent dining facilities and common room bar, where they may relax and network with others on the programme.

To check prices, availability and to book rooms please visit the Rewley House Residential Centre website. 

Enrolled students are entitled to discounted accommodation rates for the purpose of study, at Rewley House, and can contact the administration team for the promotional code to use for making online accommodation bookings via the website.

Terms & conditions for applicants and students

Information on financial support