EMC papers and articles

This page points you towards various items of interest to EMC engineers. They are provided entirely free as a service to the EMC and wider electronics communities. Papers will be added as they become available.	Mathcad files EMC-specific files in Mathcad format for various calculations and as tutorials can be found here.
	Training videos We are creating a number of short videos on EMC subjects for self-training. Visit our videos page to see.

Papers

Right-click the link and choose "Save As...". Organized into headings:

Designing for EMC
EMC Testing
PLT
Legislation and standards
Others

Designing for EMC

Designing for EMC	296k	Revised in January 2010, a noddy guide to good EMC design practice of electronic circuits.
The water-bed and the leaky bucket	508k	Published in the EMC Journal September 2010, offers an explanation of why mitigation measures for radiated emissions may have the opposite effect from what was intended
On-board shielding: principles and practice	452k	Presented at the SRCG meeting on 29th September 2010 at Tecan, Weymouth, discusses how to apply shielding cans on PCBs
Immunity requirements related to design choices	566k	Published in the September 2009 issue of the EMC Journal, considers what electronic product designers can do to improve the immunity of their designs
The Ground Plane: Lord of the Board	183k	First published in the EMC Journal issue 72, September 2007; discusses the implementation of ground planes on PCBs
Advanced Topics in EMC Design	468k	Presented at NEEDS2006 in May 2006, the IEEE EMCS in December 06 and the SCA in July 07, discusses the issues of split ground planes (don't!), decoupling capacitor selection and placement, and common-to-differential mode conversion in interface filters.
The trouble with wall-warts	28k	Originally published in EMC Journal May 05, this discusses the problems due to conducted RF emissions from wall-wart power supplies.
Shielding effectiveness of a box with a slot	324k (zipped)	PowerPoint 97 presentation showing variation of shielding effectiveness with box size, slot width and measurement position, according to the theory developed by Robinson et al at the University of York. Zip file includes animations derived from Mathcad.
Aspects of I/O filter design	120k	Presented at Newbury in 2004, discusses how you implement an interface filter and looks at its circuit model. Issues of component balance and CM-to-DM conversion are covered in detail.
Controlling resonances in PCB-chassis structures	364k	Presented in Sorrento in 2002, this paper describes the impact of structural resonances for product EMC and discusses how to control them.
Using ferrites for interference suppression	184k	This has been written to try and demystify the subject of ferrite sleeves on cables, in our experience one of the least understood aspects of EMC design. Includes several plots of actual ferrite performance.
Ground planes on low cost boards	180k	Ground planes are widely used in multilayer boards for high-performance digital circuits, but you can use them on cheap analogue-only boards for improved immunity too.
Response of 74XX logic circuits to ESD transients	77k html	Presented at the IEE in 1994, reports the results of some experiments on the ESD susceptibility of various types of flip-flop.
Cost-effective layout of microprocessor circuits	192k html	Presented at the ERA EMC-92 conference, covers some of the issues for microprocessor PCB layout and describes a training aid to help in understanding them.

EMC Testing

Some considerations for ESD testing	323k	Published in the January 2010 issue of the EMC Journal, covers the techniques and issues raised by the IEC 61000-4-2 ESD test
The FFT emission measurement method	644k	The keynote presentation at the EMCTLA FFT seminar in June 2008; introduces the technology and issues raised by the FFT method
Measurement Errors Caused by the Transient Limiter	195k	Presented at EMC Zurich (Munich) 07. Subject as below, but with more detail in the modelling.
The hazard of the transient limiter	90k	First published in the EMC Journal issue 69, discusses the errors that can be caused in the CE test by the transient limiter, and what you can do about them.
Why do I never get the same result twice?	518k	Presented at the SCA meeting on 6th September 05, examines why you may get different results for EMC emissions and immunity tests, even at the same test house on the same day, let alone from different test houses at different times.
Pitfalls and practice of IEC 61000-4-6 conducted immunity testing	1851k	Written with Richard Marshall and published in EMC Journal March 05, discusses best practice in using CDNs, EM Clamp and current probe in conducted RF immunity tests.
Emissions measurements on switch-mode power supplies	206k	Originally written as an application note for Chase EMC and published in ITEM 1993. Now updated, discusses golden product and pre-compliance testing of SMPS using a spectrum analyser, LISN and various accessories.
Measurement techniques and test methods	98k html	Presented at the ERA EMC-94 conference, is a tutorial for companies who want to invest in their own facilities for in-house EMC testing. Revised March 2000
Conducted interference	113k	This paper was written to clarify the mechanisms involved in conducted coupling, both for emissions and immunity. First presented at an IEE Colloquium in London, entitled "The Hows and Whys of EMC Design", on 30th March 1999

PLT

The Ofcom statement on PLT	152k	A discussion of the enforcement implications of the April 2011 Ofcom "supplement" on PLT. Published in the EMC Journal June 2011
Why broadband PLT is bad for EMC (again)	258k	An update of a paper first written in 2005, which remains on this website (further down this list). Published in the EMC Journal January 2009
RF emissions of Powerline Ethernet adaptors	293k	Reports the results of conducted emissions tests on a widely-used powerline modem, and discusses some implications. Published in the EMC Journal May 2009
After the EMC Directive	146k	Discusses the EC's response to complaints about PLT adaptors, and considers what this may mean for enforcement of the EMCD. Published in the EMC Journal July 2009
Why broadband PLT is bad for EMC (first pass)	266k	Written in 2005 and unpublished elsewhere, the title says it all. If you are looking at this site on a broadband connection, read this paper and ponder. A heavily revised version appeared in the EMC Journal, issue 80 January 09. See top of this list
Audio files of PLT interference		To go with the above papers, for interest. Recorded on HF with a pair of Comtrend PG902 adaptors as supplied with BT Vision, in the same room.
6.175MHz-1	MP3 1876k	Starts with a French programme on 6.175MHz, the units are switched on after 0:30 seconds; after 0:60 seconds they are transferring data, and are turned off after 1:40
12MHz-1	MP3 939k	Music programme on 12MHz, the units are switched on after 0:14 seconds
13.7MHz-1a	MP3 931k	Starts in the middle of transferring data, then transfer ends after 0:22 seconds and units are turned off after 0:34 seconds - voice programme reappears
13.7MHz-1b	MP3 931k	Starts with a music programme on 13.7MHz, the units are switched on after 0:23 seconds and stay in standby
13.7MHz-2	MP3 939k	Starts in the middle of transferring data, the transfer ends at 0:23 seconds and the units are turned off after 0:40 - voice programme reappears

Legislation and standards

Using standards under the second edition	139k	Presentation given at the EMCTLA interactive workshop in London on the New EMC Directive, 19th January 2005.
A critique of the EMC Directive	40k html	Presented in Rome in 1996, this paper reviews the operation of the European EMC Directive thus far and makes recommendations for improvements.
EMC and litigation	24k html	Presented at Zurich in 1995, describes a case heard at the High Court in which the fundamental issue was the electromagnetic susceptibility of an electronic system.

DTI-NMSPU Projects

The project on Uncertainties of Immunity Measurements has its own download page.

So does The LISNs and absorbing clamps report - a project sponsored by the UK DTI to give a guidance for best practice in testing with and calibrating the CISPR LISN and ferrite absorbing clamp.

Other papers

These two papers were originally written for Schaffner-Chase EMC (now Teseq) in 1997. They still wear quite well.

What to look for in an EMC amplifier 151kB	A review of the characteristics required for power amplifiers for RF immunity testing, and antennas for both immunity and emissions testing.
What to look for in an EMC antenna 292kB

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