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Estimated reading time: 7 minutes
Tim’s Takeaways: What More Do We Need to Know?
Although it’s been more years than I care to admit, I still remember very clearly the class on careers I was required to take in junior high school. On a table in the front of the class were several boxes filled with all sorts of different job cards that a student would search through to learn about different professions. Each card listed the schooling and experience required for that particular job, its expected responsibilities and duties, and an estimated salary. Our assignment was to choose a handful of these cards that interested us, study them, and then list the reasons why we would or wouldn’t pursue those jobs as a career.
As you might have guessed, I blew the assignment.
To be fair, the concept of preparing for a career simply wasn’t real for me at that point in my life, and I certainly didn’t have any goals in mind for my future. Looking back on it now, I realize that this class was intended for students like me who needed to discover what the future held for them, but I missed its intentions entirely. Instead, my focus in those days was band class, biking all over town with my friends, and girls—and not necessarily in that order. So, if I remember correctly, to pull at least a passing grade I gave the careers assignment a half-hearted attempt and pulled cards for an airline pilot, astronaut, and an actor. Things that sounded fun but were not very realistic.
I really wish now that I had pulled the job cards for a profession in design, electronics, or engineering. If so, then perhaps I might have chosen a path to PCB design much earlier than I did. However, I would be willing to bet that if I could go back in time and look through those boxes once again, that I would never find a specific card on PCB layout and design. Even though most people today are familiar with a circuit board, it is rare to find anyone outside our industry who understands their complex process of conception, creation, and manufacturing. And (way) back when I was in school, that entire process would have been even more of a mystery.
When I eventually started laying out circuit boards, many of the designers at the time came from a wide variety of career paths within our industry. Some came with a background in electrical engineering, while others started out as technicians, graphic artists, and even one goofy kid who started out in a PCB photography lab. (That was me in case you didn’t realize it.) PCB layout CAD systems were just coming into their own, which gave me an advantage due to my comfort level with computers.
At that time, many designers were still working on drafting boards, or taping out their layouts on a light table. Eventually those methods were completely replaced by CAD systems, which have had their own rapid growth as evolving design requirements require continual enhancements and upgrades. Now, except for legacy designs that are still built from film stored in a vault, tape-up designing is relegated to the hobbyist. But design tools and methods aren’t the only aspects of our industry which have changed over the years.
It has become essential for PCB designers to have a solid foundation of education and training to be successful in the industry. Entry-level designers today typically have a much better understanding of electronics than what we had when I first started, and those requirements are always growing.
It isn’t enough anymore to simply understand how to arrange the circuitry so that it works; it is also important to understand why that circuitry works the way that it does, along with the many conditions that can change that. In this edition of Design007 Magazine, you will see a lot of discussion about the need for designers to not only understand electronics, but also the underlying physics that is involved in the performance of circuitry. This issue would make for some interesting reading and researching for a middle-scholar studying a career card.
There is a lot to be said about the physics of electronic circuitry, but I’m going to leave that discussion to the experts in this magazine. However, it raises a question: How many other disciplines should layout designers explore to enhance their skill sets for success in our industry? Here are some areas that come to mind:
- Fabrication
- Assembly
- Component engineering
- Supply chain
- Marketing
Fabrication
Most of us who lay out circuit boards probably have a good understanding of how a PCB is fabricated. But as with any subject, there is always more that can be learned to help design a better board. Do you understand the capabilities and limitations of your fabricator(s)? Do you understand the nature and characteristics of the materials being used and how these will affect your design, especially in high-speed applications? Is it better to increase the layer count of the board for greater signal integrity, or reduce the count to minimize the cost? Understanding these various points may well end up making the difference between success or failure in your design.
Assembly
As with fabrication, there is a lot more to understand about PCB assembly than simply maintaining the correct distance between components. Most designers have a firm grasp of the basics of design for manufacturability (DFM), but do you go deeper into these subjects by applying the correct DFT, DFA, DFF, and other DFX rules? Do you know that the DFM rules will change depending on what soldering method is used to build the board? Have you placed your parts to also allow for easy access of cables, switches, and other human interfacing parts during system assembly? Many boards are laid out with adequate part spacing but fail because a connector was rotated incorrectly for its mating cable.
Component Engineering
When you begin a new circuit board layout, do you jump right in, or do you verify that the parts being used are correct? There are many factors that can affect a part, including its availability and cost, to say nothing of its electrical performance. Often a design will come through with parts that are out of date because the schematic was built using copied sheets from an older design. PCB designers need to check for all these potential problems and understand how to resolve any that they find.
Supply Chain
Speaking of component price and availability, do you keep your finger on the pulse of what parts should or shouldn’t be used on a board? A circuit board job can come to a screeching stop during assembly because the parts they rely on are no longer available. PCB designers should at least have resources, like their manufacturing partners, that they can use to verify the parts before they finalize the design.
Marketing
Do you know the purpose of your design, where it will be used, and how? These details can impact the operation of the board which could change how it should be designed. Also, simply understanding the product’s schedule and requirements could help you to plan for and hit design benchmarks that will help marketing to be more successful.
But Wait, There’s More
These are only a small sampling of the topics that today’s designers should include in their repertoire of knowledge, and there are many more that we haven’t even touched on. For instance, a designer should be fluent in the CAD tools being used and have a solid understanding of how they interreact with other systems and third-party tools. This can greatly enhance your design productivity and ultimately the success of the project you are working on.
All these additional topics may seem like a lot for a designer to grasp, but one of the defining characteristics of our industry is the need to continually grow in our knowledge and skills. PCB designers must stay on the forefront of new ideas and technology, and in that regard, I believe the ability of designers to learn and adapt is no different now than when I first started.
Sure, the specific knowledge base and skill sets required now are much more advanced than they were 40 years ago. After all, we were just coming up to speed on PCB CAD systems and surface mount components. Today’s concerns about the physics that affect high-speed design performance were not ideas that most designers would have even considered let alone designed for. But just as we triumphed over the new requirements confronting us back then, it is my firm belief and expectation that today’s designers will expertly adapt and grow with the new responsibilities facing them.
It is a genuine pleasure to see the changes that are spreading throughout our industry, and the growth that is occurring. It really is exciting to see where the next great steps in our industry will take us. Until next time, keep on designing.
This column originally appeared in the November 2022 issue of Design007 Magazine.
More Columns from Tim's Takeaways
Tim’s Takeaways: One for the ArchivesTim’s Takeaways: The Art of Technical Instruction
Tim’s Takeaways: PCB Design and Manufacturing—Let’s Work Together
Tim’s Takeaways: Take It From Scotty, Simple Really is Better
Tim’s Takeaways: Human Ingenuity and the Rigid-flex PCB
Tim’s Takeaways: How I Learned Advanced Design Strategies
Tim’s Takeaways: Batter Up—Stepping Up to the Substrate
Tim’s Takeaways: Tribal Knowledge—Not the Villain You Thought