“Bogatin’s Practical Guide to Transmission Line Design and Characterization for Signal Integrity Applications” – A Review

Everything you ever wanted to know about PCB transmission lines – and more – in a digestible format with just the right amount of math to back up the illuminating practical illustrations.


Ed.: Martyn Gaudion is managing director of Polar Instruments Ltd. He began his career at Tektronix in test engineering on high-bandwidth portable oscilloscopes. He joined Polar in 1990, where he was responsible for the design and development of the Toneohm 950, Polar’s multilayer PCB short circuit locator. He became CEO in 2010. He also develops tailored content for the Polar YouTube channel. He reviewed this book for PCD&F.

Hot off the virtual press – a copy of Dr. Eric Bogatin’s new guide to transmission line design appeared in my Artech eBook account.

Do we really need another transmission line book? That’s what Dr. Bogatin asks right at the outset. After reading this new tome from virtual cover to cover, yes we do. This is a thoroughly practical book an peppered with links to Bogatins’s brief informative video explanations which expand and add dynamic content in a way that printed matter alone cannot.

Whether you are a recent graduate who wants a more practical insight to the behavior of transmission lines after doing all the hard work of the pure math side of study, or an experienced electrical engineer moving into the high speed arena – or even a PCB technologist or fabricator wanting an insight into all the mysterious terminology that surrounds the subject – this is a resource book for you. It is equally valuable whether you are dipping into chapters of specific interest, or taking a deep breath and reading from (virtual) cover to cover.

In my day job I spend most of my time helping customers who are new to transmission lines ensure that they document and design them correctly for fabrication, and I confess over the years much is taken as given. By reading Bogatin’s new book I have gained insight into transmission line behavior that is very familiar but I didn’t know the why – and the why makes everything make more sense. 

It is staggering that the electrical behavior of a simple pair of copper traces with a sandwich of dielectric material can generate a book running to 600 pages without loss of interest, but this is exactly what Bogatin does with the subject. Along the way you will find out why you should always think of signal and return paths and not in terms of signal and ground. You will find that while the RF and digital design spaces may run at similar frequencies, the design considerations for both are poles apart. (No pun intended.) You will also discover that simulators and field solvers don’t design circuits – you do – and you best have an idea of what you intend to happen and the expected outcome before reaching for the simulator. Words are important, and Bogatin stresses that though digital and RF and EMC specialists all deal with high-speed signals – and a lot of the jargon is similar – there are often situations where technical terms overlap while their meanings don’t. Bogatin takes an important stance in defining and understanding the terminology to ensure you are understood when working across disciplines.

On measurement – there are many precision tools for measuring high speed signals and time and frequency domain information, all with accuracy beyond your dreams – but as with simulation – Bogatin cautions that unless you understand what you are measuring and how to design your test vehicle, any or all of that expensive equipment can lead you to the wrong answer. Time spent in the measurement section of the book is well invested and will enable you to extract the best possible measurements from whatever TDR/sampling oscilloscope/vector network analyzer you have to hand.

I personally like the examples where Bogatin mixes electronic timescales in nanoseconds with human relatable timescales (days) to bring tangible meaning to his explanations. I also like his informative section on why intuition in the frequency domain does not translate easily (at all?) to the time domain, and that while both are valid and useful you need to work with a degree of selective schizophrenia while working in these domains.

Last but not least, alongside the video links and examples are links to both evaluation versions of commercial tools and useful no cost utilities so you can run the simulations and experiment for yourself.

Martyn Gaudion, June 2020

Bogatin’s Practical Guide to Transmission Line Design and Characterization for Signal Integrity Applications

by Dr. Eric Bogatin

Available from Artech House

Chatting Away

We had a great premiere of PCB Chat last week. Eric Bogatin, the signal integrity guru, hosted the nearly two hour session, answering more than 20 questions.

The transcript can be seen here (you must be signed in to Printed Circuit University to view it; registration is free).

The next chat will be Feb. 7 with SMT process consultant Phil Zarrow. Note that you don’t need to make the live session in order to ask a question: questions may be submitted in advance.

If you have recommendations for future moderators, drop me a line or post in the comments. Thanks!

PCB Chat Premieres

We had a great premiere of PCB Chat yesterday. Eric Bogatin, the signal integrity guru, hosted the nearly two hour session, answering more than 20 questions.

The transcript can be seen here (you must be signed in to Printed Circuit University to view it; registration is free).

The next chat will be Feb. 7 with SMT process consultant Phil Zarrow. Note that you don’t need to make the live session in order to ask a question: questions may be submitted in advance.

If you have recommendations for future moderators, drop me a line or post in the comments. Thanks!

Bogatin ‘Signals’ Chat Intent

UP Media Group Inc. today announced Dr. Eric Bogatin will moderate the industry’s first “chat,” an open question/answer session using pioneering new software developed by UPMG.

The premiere event will be held Jan. 26, from 2 to 4 p.m. Eastern time, at Printed Circuit University. The second chat will feature SMT consultant Phil Zarrow and takes place Feb. 2 from 2 to 4 p.m. Eastern.

“Chats” refer to moderated question/answer sessions between an expert on a particular topic and any number of parties interested in the subject. Chats are conducted online, and attendees can submit questions privately via email in advance of the chat, or while the chat is live.

Moderators review the questions and choose which will be answered. As questions are answered, they appear online in sequential fashion. After each chat session is over, the transcript is made available for on-demand viewing. Transcripts are also searchable.

PCB Chat is an environment that emulates and captures the essence of online shared group communication without all the chaos of a free-form chat room. A chat operates more like the end of a presentation, where the audience asks questions of the speaker. It is controlled and systematic, and the moderator has full control over which questions or comments to address, ensuring the chat stays on topic.”

UPMG has invested several months of development work to realize the new software platform for PCB Chat.

Dr. Bogatin is perhaps the leading expert on printed circuit board signal integrity and transmission lines. He has a bachelor’s in physics from MIT, and master’s and Ph.D. degrees in physics from the University of Arizona. He has held senior engineering and management positions at Bell Labs, Raychem, Sun Microsystems, Ansoft and Interconnect Devices. A prolific author, Dr. Bogatin has written six books on signal integrity and interconnect design and over 200 papers, including a regular column in PCD&F. He also has taught over 6,000 engineers over the past 20 years.

PRINTED CIRCUIT DESIGN & FAB and CIRCUITS ASSEMBLY magazines are media partners for the event.

December Issue Now Online

The December issue of PCD&F is now available.

Our cover story is a study of a novel halogen-free, phosphorus-free laminate said to be
effective for lead-free processing but without the cost penalty typically associated with such materials.

Other highlights include:

And our commentary on the recent Productronica trade show.

Check it out here!

PCU Goes Live!

As “Dean Pete” (I think Professor Pete sounds better) intimated earlier today, we have just gone live with Printed Circuit University, the industry’s first online e-learning and training resource for professionals involved in the engineering and design of printed circuit boards and related technologies.

Printed Circuit University is built on the robust, established and time-proven beTheSignal e-learning platform, and features instruction by SI guru Dr. Eric Bogatin.

Pete and VP of Sales and Marketing Frances Stewart are demonstrating Printed Circuit University this week at DesignCon in the Santa Clara. Be sure to stop by and take a look at what promises to be the future of printed circuit board design education and training.

DesignCon Day 2

Yesterday was the typical busy day for media types like yours truly. A quick breakfast with a couple of the exhibitors and then some editorial meetings. It has been several years since I wore the editorial hat at a trade show and I’d forgotten how distracting it can be to have a business conversation in an open space. Especially when people I hadn’t seen in 8 years or so would walk by and wave. The only thing that saved me was the fact that this is such a small and incestuous industry that the same thing was happening to the person I was interviewing.

I was reminded in one of the sessions Tuesday that the whole EDA market — boards, chips everything EDA, is smaller than Wal-Mart. Just an fyi to put things into perspective.

A couple of notes on the tech conference. DesignCon is trying to address the PCB side of the design world. They’ve put most of the emphasis on signal integrity, bringing in heavy-hitters like Bruce Archambeault, Lee Ritchey and Eric Bogatin. I also saw Rick Hartley on the show floor but don’t think he is speaking this week.

Some things I learned Tuesday. Rogers, the laminate supplier known for RF and microwave applications, is committing considerable resources to the digital market with its Theda products. I want to specifically thank Sean Mirshafiel, a market development manager at Rogers, for a conversation that educated me to some of the finer points of of copper laminate. Sean provided me with the seeds of several articles topics that we’ll talk about in PCDF soon.

Bhavesh Mistry and Vince Accardi of National Instruments brought me up-to-date on release 11 of the Multisim simulator for both academia and the commercial marketplace. Multisim is integrated with National’s NI Ultiboard layout software and its NI LabVIEW measurement software.

Today I have a couple of test drives with some EDA people and I’m looking forward to getting my hands dirty.