Flexible Thinking: Designing Flex Circuits for Dynamic Reliability
Global PCB Connections: Rigid-flex and Flexible PCBs—The Backbone of Modern Electronics
Happy’s Tech Talk #29: Bend-to-Install Semi-flex FR-4
Setting Design Constraints Effectively
July 31, 2025 | Stephen V. Chavez, Siemens EDAEstimated reading time: 2 minutes
PCB design requires controlling energy within the medium of a PCB. The manner in which we control the chaos of energy is by implementing and utilizing physical and electrical rules, known as constraints, along with a specific structure and material(s) that make up what is known as the foundation of the design. These rules govern everything within the PCB structure and generally fall into two camps: performance and manufacturability. Setting this foundation correctly is extremely important and the key to success.
At times, especially with very complex designs, it’s no easy task to make sense of these rules while creating and implementing these design constraints. It can be daunting and time-consuming. How many times during the initial phase of the design process have we heard project management ask, “What is taking so long? Why haven’t you started placing components and routing? Why do you even need constraints?”
I’m sure many can relate to such questions. The goal for any PCB design is to be “correct by construction,” where you have the highest potential for first-pass success. This means that revision 1 works with no respins required, and there are no interruptions in the process of getting the product to market as fast as possible. This is accomplished by implementing and utilizing design constraints along with industry best practices, which are vital toward achieving PCB design success.
Design constraints are typically derived from customer requirements. Depending on the intended function of the end product, how it needs to function and under what conditions it needs to operate are the keys to deriving the specific details of the actual constraints to be implemented in your design. Make sure you work closely with your manufacturers (both fabrication and assembly) from the very beginning of the project and throughout the design process. I cannot stress enough that close collaboration with your manufacturers, also known as your external stakeholders, is key to downstream success.
To continue reading this article, which originally appeared in the July 2025 issue of Design007 Magazine, click here.
Share on:
Testimonial
"We’re proud to call I-Connect007 a trusted partner. Their innovative approach and industry insight made our podcast collaboration a success by connecting us with the right audience and delivering real results."
Julia McCaffrey - NCAB GroupSuggested Items
New Book Explores How UV Technology Is Transforming Electronics Protection, Efficiency, and Sustainability
05/14/2026 | I-Connect007I-Connect007 proudly announces the recent release of The Printed Circuit Designer’s Guide to…™ UV Curable Conformal Coatings. Authored by respected industry technologists Brian Chislea and Cody Schoener, PhD, of Dow, Inc., this new volume offers a comprehensive exploration of UV-curable conformal coatings and their expanding role in improving the protection, performance, and sustainability of electronic assemblies.
Siemens Expands EDA Software Access Through EuroCDP Project
05/14/2026 | SiemensSiemens has become the first software provider to sign a strategic framework agreement with the European Chips Joint Undertaking (Chips JU) which aims to bolster Europe's semiconductor industry by fostering collaboration between the EU, member states and the private sector, through the European Chips Design Platform (EuroCDP) project.
Rethinking Stackup, Materials, and Tolerances in Modern Designs
05/14/2026 | Kristin Moyer, Global Electronics AssociationThe simple rectangular rigid PCB is becoming increasingly infrequent. This reality necessitates designing with concepts well outside traditional rigid PCB methodologies. For example, the designer of wearable electronics may need to implement conductive fibers integrated into the textile material. Heads-up displays, like those in VR/AR headsets and glasses, require transparent circuitry etched into the display glass. The process of designing without a rule book usually starts with something other than the traditional board design process.
New Courses: Advance Your Electronics Expertise in June and July
05/14/2026 | Global Electronics AssociationStay current with design, manufacturing, and quality standards by enrolling in one of these online instructor-led courses starting in June and July from ElectronicsU at the Global Electronics Association, designed to help professionals at every level sharpen their skills and advance their careers. These live, expert-led sessions combine flexibility with real-time interaction, allowing participants to learn directly from seasoned industry professionals while collaborating with peers worldwide. Access to all applicable IPC standards is included in the courses.
Road to Reliability: Engineering High Uptime EV Charging Infrastructure
05/13/2026 | Stanton Rak, SF Rak CompanyThe transition to EVs is no longer constrained solely by vehicle capability. Instead, it is increasingly defined by a simpler, but more unforgiving question: Will the charger work when I arrive? This high uptime does not happen by accident. As EV technology has matured, limitations in battery range, power electronics, and thermal management are no longer the primary barriers to adoption.