Elementary, Mr. Watson: Rein in Your Design Constraints
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Showing Some Constraint: Design007 Magazine July 2025
July 10, 2025 | I-Connect007 Editorial TeamEstimated reading time: Less than a minute
Constraints shape the entire PCB industry, and every design decision introduces trade-offs, often leading to more trade-offs. Nearly every element on the board can become a constraint depending on the end product: component and drill sizes, trace widths and spacing, material choices, microvias, testing requirements, signal and power integrity, thermal demands, fabricator limitations, and supply chain risks. The list doesn't stop there. It can also include compliance with FCC, FDA, UL, and ITAR regulations.
Building a smart constraint strategy that balances electrical and manufacturing needs takes deep experience, often years in the making. Fortunately, our expert contributors, many of whom are also educators, bring exactly that level of insight. This month, we explore design constraints: the essential requirements, common challenges, and proven best practices for getting them right.
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Elementary, Mr. Watson: Rein in Your Design Constraints
07/10/2025 | John Watson -- Column: Elementary, Mr. WatsonI remember the long hours spent at the light table, carefully laying down black tape to shape each trace, cutting and aligning pads with surgical precision on sheets of Mylar. I often went home with nicks on my fingers from the X-Acto knives and bits of tape all over me. It was as much an art form as it was an engineering task—tactile and methodical, requiring the patience of a sculptor. A lot has changed in PCB design over the years.
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