-
- News
- Books
Featured Books
- design007 Magazine
Latest Issues
Current IssueAll About That Route
Most designers favor manual routing, but today's interactive autorouters may be changing designers' minds by allowing users more direct control. In this issue, our expert contributors discuss a variety of manual and autorouting strategies.
Creating the Ideal Data Package
Why is it so difficult to create the ideal data package? Many of these simple errors can be alleviated by paying attention to detail—and knowing what issues to look out for. So, this month, our experts weigh in on the best practices for creating the ideal design data package for your design.
Designing Through the Noise
Our experts discuss the constantly evolving world of RF design, including the many tradeoffs, material considerations, and design tips and techniques that designers and design engineers need to know to succeed in this high-frequency realm.
- Articles
- Columns
- Links
- Media kit
||| MENU - design007 Magazine
Getting Signal Integrity Right by Design
July 27, 2016 | Narayanan TV, ZukenEstimated reading time: 2 minutes
As clock frequencies increase and active devices and interconnect traces shrink and are placed ever closer together, signal integrity (SI) becomes an increasing challenge. Today, SI is typically addressed late in the design process after the PCB layout has been completed by performing complex and time-consuming 3D extractions and simulations for high-speed lines.
But with little attention being paid to SI during the layout process, simulation frequently identifies numerous SI problems. Multiple design and simulation iterations are often required to resolve these issues, in some cases causing delays in bringing the product to market and increasing nonrecurring expenses. An embedded SI checker helps by automatically checking for common mistakes that frequently cause SI problems such as missing shielding, return path discontinuities, ground or power loops, impedance mismatches, etc. Even with this approach, simulations are still required as a final check, but reducing the number of issues that must be addressed at this late stage helps bring the product to market faster and reduces engineering costs.
SI Design Challenges
Increasing data rates, higher IO counts and greater design complexity are leading to greater challenges in meeting SI and electromagnetic interference (EMI) requirements. For instance, 3DIC technology utilizes through-silicon vias (TSVs) to eliminate bond wires and further reduce interconnection distance in stacked chip configurations, providing higher speed performance and lower power consumption at the cost of creating many new opportunities for harmful radiation. Meanwhile, regulatory authorities are tightening electromagnetic compatibility (EMC) requirements by requiring compliance at higher and higher frequencies. The trend towards integrating multiple radios—each of which is an intentional radiator—into electronic products creates further challenges.
But the complexity of today’s designs and the high levels of automation required to complete them in a reasonable time period usually prevent electrical designers from paying more than cursory attention to SI during the design process. Nearly all PCB design tools have built-in design rule checkers (DRCs) but they typically evaluate the design from a manufacturability perspective, rather than from an SI perspective. Simulation is normally performed after the design has been completed, when it becomes possible to model its performance by calculating a 3D solution of Maxwell’s equations, which provides an elegant mathematical representation of electromagnetic interactions. The result, all too often, is that large numbers of SI problems are identified at a point relatively late in the design process when changes are very expensive to make. As a general rule, the cost of design changes generally increases by an order of magnitude or more as the design moves from conceptual to detailed to simulation.
To read this entire article, which appeared in the July 2016 issue of The PCB Design Magazine, click here.
Suggested Items
Facing the Future: Time for Real Talk, Early and Often, Between Design and Fabrication
07/08/2025 | Prashant Patel -- Column: Facing the FutureThere has always been a subtle but significant divide between those who design and those who build printed circuit boards. It’s not a hostile gap, but it is a real one, and in today’s high-speed, high-complexity, high-stakes environment, that gap is costing us more than time and yield. It’s costing us innovation.
DownStream Acquisition Fits Siemens’ ‘Left-Shift’ Model
06/26/2025 | Andy Shaughnessy, I-Connect007I recently spoke to DownStream Technologies founder Joe Clark about the company’s acquisition by Siemens. We were later joined by A.J. Incorvaia, Siemens’ senior VP of electronic board systems. Joe discussed how he, Rick Almeida, and Ken Tepper launched the company in the months after 9/11 and how the acquisition came about. A.J. provides some background on the acquisition and explains why the companies’ tools are complementary.
Elementary Mr. Watson: Retro Routers vs. Modern Boards—The Silent Struggle on Your Screen
06/26/2025 | John Watson -- Column: Elementary, Mr. WatsonThere's a story about a young woman preparing a holiday ham. Before putting it in the pan, she cuts off the ends. When asked why, she shrugs and says, "That's how my mom always did it." She asks her mother, who gives the same answer. Eventually, the question reaches Grandma, who laughs and says, "Oh, I only cut the ends off because my pan was too small." This story is a powerful analogy for how many PCB designers approach routing today.
Connect the Dots: The Future of PCB Design and Manufacturing
07/02/2025 | Matt Stevenson -- Column: Connect the DotsFor some time, I have been discussing the increasing complexity of PCBs and how designers can address the constantly evolving design requirements associated with them. My book, "The Printed Circuit Designer’s Guide to… Designing for Reality," details best practices for creating manufacturable boards in a modern production environment.
Siemens Turbocharges Semiconductor and PCB Design Portfolio with Generative and Agentic AI
06/24/2025 | SiemensAt the 2025 Design Automation Conference, Siemens Digital Industries Software today unveiled its AI-enhanced toolset for the EDA design flow.