Issue link: https://iconnect007.uberflip.com/i/1369942
MAY 2021 I DESIGN007 MAGAZINE 87 he shines a light on factors that may not always be apparent to the typical PCB designer. We know that our readers love lists, and this seven-step primer for designing stackups with SI in mind will not disappoint. Layer Stackup, Short and Sweet As Cherie Litson of Litson1 Consult- ing notes in her article, there are so many ways to do a layer stackup for your PCB, but there are almost too many options available today. Che- rie helps clear away some of the confusion about stackup options, drilling down to what works, what doesn't work, and why. Bonus: Cherie even includes a formula for calculating the number of signal layers for a design. OEMs Must Own the Stackup Who owns the stackup design pro- cess? Is it the OEM's design team, which is familiar with all the electrical requirements of the PCB, or the fabri- cator, who knows far more about the manufacturing process? In this interview, Bill Hargin of Z-zero, a stackup optimization software tool com- pany, explains why he believes many of today's stackup miscues stem from OEMs who refuse to take ownership of the stackup. Don't miss this article. Stackups: Properly Conveying Your Info to the Fabricator Most designers would agree that communication with the fabricator can preclude many of the problems they face. In this column, Mark Thompson of Monsoon Solutions discusses how to create the perfect board stackup, specify what you truly want to convey to the fabricator, and eliminate conflicting information about stackups. Martyn Gaudion on Stackup Design Considerations The I-Connect007 team met with Martyn Gaudion of Polar Instruments to discuss the ins and outs of stackup design, and why designers seem to be getting stackups wrong, especially if a board is going into volume production overseas. He also focuses on the many trade-offs involved in even the simplest stackup design today. In almost every conversation with PCB designers and design engineers about challenges they face— not to mention our reader surveys—stackup design is a recurring theme. The stackup, sometimes described as the "backbone of the PCB," continues to perplex even veteran designers, often due to a lack of communication between OEMs and fabrica- tors. So, this month, we're including links to some of our recent coverage of PCB design stackups. If you missed these pieces before, here's another bite of the apple! TTM's Approach to Stackup Design: Train the Customer In this interview with the I-Connect007 Edi- torial Team, TTM's Julie Ellis and Richard Dang drill down into stackup design. They detail some of the common stackup challenges that their customers face when designing for both prototype and volume levels and offer advice to designers or engineers who are struggling with stackup issues. Stackup Planning: Three Decades of Innovation This column by iCD's Barry Olney is a gift that keeps on giving: He includes a dozen links to his past Design007 columns that focus on stackup design, with an emphasis on signal integrity. Barry also discusses the current best practice for high-speed stackup design, as well as tips on utilizing field solvers and incorporating multiple technologies in a stackup. It's all here. The Magnitude of Stackup Considerations When Michael Creeden of Insulec- tro was asked to write this feature on stackup creation, he paused at the magnitude of the subject. He noted that stackups are similar to the frame- work used to pour concrete—you need to get the framework right because the framework has such a big impact on the final outcome. Seven Tips for Your Next Stackup Design University of Colorado-Boulder instructor Eric Bogatin's feature on stackup design was written from his viewpoint as the Signal Integrity Evangelist, and A Roundup of Stackup Coverage