Reading time ( words)
I remember the first time my boss asked me to design a PCB for some in-house testing. It was wintertime and we were in a meeting room with a few other co-workers. Someone suggested we design our own PCBs for testing to mitigate issues from the set-up with development kits. My boss agreed, and everyone turned to me, an electrical engineer.
Immediately, anxiety started spreading through my entire body. I could feel my palms sweating and my heart rate increase as reality hit me; I had never designed an entire board by myself before. Until then, I had read books, blogs, magazine articles, and Altium support pages on how to use their tools. I had watched countless YouTube videos, done some of the sample projects on my own, and retouched some of the existing designs. However, I had never designed an entire PCB on my own from start to finish.
I felt like there was still so much I needed to learn, and I was terrified I wouldn’t be able to deliver. Despite the panic setting in and my legs shaking from anxiety, I blurted out, “No problem. I can do it.” Everyone in the room nodded at me and we moved on to the next topic.
I barely remember what was discussed during the remainder of that meeting. All I could think was, “How am I going to pull this off? What in the world am I going to do?” I was trying to calculate in my head how many hours it would take for me to thoroughly read the 1,500-page Printed Circuits Handbook by Happy Holden and Clyde F. Coombs. In that moment, it didn’t matter how small or straightforward the PCB was supposed to be, I felt like I wasn’t prepared enough to do this on my own. But there is a reason why some parents effectively teach their kids to swim by throwing them into the deep end of the pool and letting them figure it out on their own.
When I calmed down a little bit from the initial shock (of being asked to do my job), I remembered that I had designed circuits and complex electronic systems before. I realized that I had the knowledge and the resources to complete this task, and all I needed to do was implement it into a new application. I started by reading the main IC’s datasheet and I found a reference design for the part, as well as design suggestions and additional part recommendations. Most (if not all) ICs have reference designs in their datasheets, and they are a great starting point for designers. I created a schematic, ran my design rule check and surprisingly, everything passed.
I moved on to layout. Once I got started, the whole process was flowing. At that point, I couldn’t remember why I was initially so stressed out about it. I had some doubts and worries along the way, but I was hoping if I had followed all the rules and design specifications that the board would work. After a nerve-wracking two weeks for fabrication and assembly, the boards came back fully functional, and we still use them to this day.
Looking back, I realize that experience played a big part in my PCB design education; everyone has to start somewhere. As I was designing more boards and working on more complex designs, I got comfortable using the tool and more confident about my skill. Even as I was gaining more experience, I still had ups and downs along the way.
There was a time I sent out boards for fabrication and heard back from the manufacturer that my design was not manufacturable. I’ve had to modify designs quickly in order to meet deadlines and schedules, and I’ve made hand alterations when I have accidentally missed something in the design. All of it—the good and bad—was the best thing that could have ever happened to me. Being under pressure to deliver functioning boards, on time, made me aware of what could go wrong, and it forced me to employ a systematic approach to every design I work on. I started keeping notes of the tricks I learned along the way and because of that, I ensured that I wouldn’t make the same mistakes again.
Here are some of the design practices that I’ve been following while designing boards.
1. Understand your manufacturer’s capabilities.
Altium Designer allows designers to set rules to anything you want: trace width, spacing, impedance control, via size, etc. But it is important to be aware that once you are done with your design, you need to send it to a fabricator to bring it to life. Unfortunately, designers sometimes create designs that are not feasible in real life. I’ve found that it is best to speak to your fabricators first and understand their design limitations and capabilities. There are industry standards that can be followed, but for more complicated designs that are constrained with space and rules, it is always best to start with getting all the information you need to deliver the best design.
2. Understand your design requirements.
I always spend a significant amount of time understanding what needs to be done and familiarizing myself with the parts. Reading the datasheet and application notes thoroughly can considerably decrease the amount of time you spend on the design. In addition, I like to validate my designs before I send them out for fabrication. By simulating and testing the design beforehand with software, development kits, and breadboard components, I ensure design functionality and have the freedom to test multiple configurations of the design before I hand off the data package. It also makes me more confident about my design.
3. Set the rules.
Make sure to set all your rules before you start working on layout. This can make your life exponentially easier, and it helps prevent mistakes along the way.
4. Note the lessons learned.
After you are done with a design and you are ready to work on the next revision, always review what you did, what went wrong (if anything), and identify areas for improvement. Mistakes happen, but if you hold yourself accountable for what you created, you’re going to see that there is always something you can do to improve your designs.
5. Never stop learning.
Finally, always continue your design education. You can’t rest for too long, because technology is constantly evolving. When I am working on something new, I always try to get my hands on as many resources as I can. Maybe I haven’t thought of an idea that someone else already encountered and I can learn something new. It’s always good to try to expand your knowledge; you never know when a tip or technique will come in handy.
As with most things, I believe experience plays a big part in PCB design, so I try to practice as much as I can on my own. I feel like I still have so much to learn, but I am excited to try out some new techniques I’ve read about, and I hope that one day, if I keep this up, I can become a great designer.
Tamara Jovanovic is an electrical engineer at Happiest Baby Inc., a developer of smart baby beds based in Los Angeles, California.
This article originally appeared in the August 2021 issue of Design007 Magazine.