Elementary, Mr. Watson: Eating the Elephants of Your PCB Design

After being in the PCB industry for 20 years, I have had the opportunity to work with some of the best PCB designers and engineers in the field. I have seen that there are some common traits between the good ones vs. the great ones. How they handle the PCB design process, especially when problems arise, is impressive to watch. Fortunately, these traits are not something that someone is born with but rather skills they learn. No matter where you are in your career, you can learn new, better abilities to move forward.

One of the most significant traits I have seen is the ability of PCB designers to compartmentalize the PCB design process. There is a riddle that goes, “How do you eat an elephant?” The reply is, “One bite at a time.” The ability to deal with the next few steps in from of you and work through those issues is vital in the PCB design process. The moral of the story, as they say, is to work through things one step at a time.

In this column, I will share some of the other traits PCB designers need, and how you can implement them into your design process to become a great designer.

Find the Root Cause of Issues

PCB design is not a static situation but rather a very dynamic one. Many times, problems will occur during the design process. The ability to find and analyze the root cause of a problem is vital. If we only look at the cosmetic, surface challenges without digging into the problem to determine the root cause, we may never find the true cause of our problem.

An excellent way to analyze and determine any root cause is to go through a line of questioning called “the five whys.” When you the question “why,” it gets down to the real motivation of an issue. That line of questioning can go further, but five iterations of asking “why” are generally sufficient to get to a root cause. Let’s look at an example of using “the five whys.” 

In this example, the problem is the room lights do not turn on.

  1. First Why: You blew a fuse in the panel.
  2. Second Why: There’s a short across a circuit.
  3. Third Why: There’s shorted house electrical wiring.
  4. Fourth Why: The house wiring was far beyond its service life and not replaced.
  5. Fifth Why/Root Cause: The house wiring was not kept up to code.

When solving these issues, you begin with the root cause and work your way back to the problem.

I can say a lot about this because it is a vast area. I would highly recommend for you to study and start using it.

Change Is Good

No one seems to like change. Even when you have problems and issues in your process, it is never analyzed with “the five whys” and fixed. The common practice is to bury your head in the sand and hope it all just goes away. The truth is that PCB designers are responsible for identifying issues and knowing how to fix them.

Know What the Component Library Represents

How you begin to look at what your library represents is a philosophical change. The library is the most critical piece of your PCB design process, by far. I have always found that the librarian is one of those individuals who hold an essential position in the company.

Once you realize the importance of the library, know that the library represents a vast resource to the company. That initial data is the foundation in which you will build every PCB design. The library embodies money to the company—either a profit or a loss.

Set Gatekeeping Items in Your Process

One of the significant changes I saw in our procedures was allowing the data to drive the process. An excellent example of this was that when we created a new component. We were allowed to use that component in a particular design, but we had a gatekeeping item of not allowing the PCB to be released for fabrication until that single component was verified and released.

In this way, we protected ourselves from introducing unnecessary risks to our design. You will begin to see that throughout the design process, you must have these gatekeeping items. When you stop everything, look at where you are and make sure you still are headed in the right direction.


In the classic 1967 film “Cool Hand Luke,” starring Paul Newman and George Kennedy, there is the famous tagline of, “What we’ve got here is a failure to communicate.” That can be a significant problem in the PCB design process if you let it. As PCB data management has become more of our focus, there has been a massive increase in communication with various roles involved. This has moved the entire design process from being a single activity done by a sole person instead of being a team sport.

That was a direct result of focusing on the specific data used by certain individuals at particular points in the process. For example, as the project would move from out of component placement on the PCB, it would walk it over to the mechanical engineer to check the product mechanicals. We saw an increase in communication at key points in the design, which significantly improved the entire workflow of the design.

Tailoring (Constantly Improving)

PCB data management did not end once we got the PCB design over to the fabrication house; that was only the starting point. Because of the dynamic aspects of the data we used, we needed to improve continuously on the information we use. We found we focused much more on the backend of the process than the beginning. We allowed what we produced, and several specific reports from a PCB build, to go back to our component library.

Using excellent root-cause analysis, we determined if any problems we experienced were a result of a defective component in our library. In other words, the process is not a straight line but a circle that feeds back unto itself. It’s a never-ending process.


The specific changes that may occur with your situation most likely will be different; however, you must be willing to walk through and find the root causes of issues. Allow the solutions you find to change your process. That is where I have seen a significant change. Nothing with your process should you set in stone. Always look to make improvements, which takes courage because it is challenging to see what mistakes you made.

Be proactive regarding changes. Make changes when you can rather than when they become an emergency, and money and time have been lost on a PCB build. It’s much easier to think through the problem when it is not an emergency for you.

John Watson, CID, is a senior PCB engineer at Legrand Corporation.



Elementary, Mr. Watson: Eating the Elephants of Your PCB Design


After being in the PCB industry for 20 years, John Watson, CID, has had the opportunity to work with some of the best PCB designers and engineers in the field. He shares some of the traits PCB designers need, and how you can implement them into your design process to become a great designer.

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Elementary, Mr. Watson: Rebuilding Trust When Things Go Wrong


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Elementary, Mr. Watson: What You Need to Know About a PCB Design Career


Never stop learning. Why? Because the industry never stops changing. Those that continuously stay in that state of learning are the ones who succeed. The old saying “Knowledge is power,” often attributed to Sir Francis Bacon, has never been truer. Fortunately, there is never a lack of things to learn. Don’t ever become apathetic about learning. Make a point of keeping a running list of ideas or subjects that you want to research, and then purposely set aside time in your week strictly to study and learn about these things anywhere you can.

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