Issue link: https://iconnect007.uberflip.com/i/1535183
26 DESIGN007 MAGAZINE I MAY 2025 I've oen been asked, "Can you have a per- fect PCB design?" At first blush, it seems like the answer should be yes. Aer all, if you fol- low all the rules, double-check your work, and use the right tools, it should be perfect. Right? I have oen used the analogy that a PCB design is like a giant complex puzzle, with one caveat: ere is not a single solution but rather an endless number of possible solutions. e truth is, designing a PCB is more than just put- ting together a complex puzzle, because pieces sometimes change shape while you're still working. To make things even worse, a PCB design contains two types of information: static and dynamic. Static information is fixed and doesn't change. On the other hand, dynamic informa- tion is connected to your design and constantly changes. As you have probably guessed, the dynamic data and changes wreak havoc on your design. Although we are looking specifically at the output data in this column, it's important to fully grasp the big- ger picture as well. In a PCB design, there is an interrelationship between every process stage, oen called a parent-child relationship. e library is the parent of the schematic, the schematic is the parent of the PCB design, and the outputs and documents at the end are the children of these. So, a seemingly insignificant error in a PCB design can oen evolve into a significantly larger issue due to the intercon- nected nature of the design process. It is the ultimate "tail-wagging-the-dog" scenario. A few Stephen R. Covey concepts fit nicely into what we are discussing here: the Circle of Control and the Circle of Influence, intro- duced in his classic business textbook e 7 Habits of Highly Effective People. As Covey explains, your Circle of Control includes every- thing you care about or worry about—things that affect your work or life that you can directly control. e other is the Circle of Influence, which is things that are out of our con- trol, but still possi- bly under our influ- ence because of what we can control. As a PCB designer, there are many things that you are fully responsible for and have direct control over. ese fall into your Circle of Control. is includes ensuring that your schematic and layout files are clear and complete. Your bill of materi- als (BOM) must be accurate and current. It's essential to check that all your footprints, pad Elementary, Mr. Watson Feature Column by John Watson, CID Design Data Packages: Circle of Concern or Circle of Influence?