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Moving From 28 Gbps NRZ to 56 Gbps PAM-4: Is it a Free Lunch?
09/19/2018 | Yuriy Shlepnev, Simberian
Judy Warner: AltiumLive’s Second Year to be Even Better Than First
09/19/2018 | Andy Shaughnessy, Design007
PCB Design Challenges: A Package Designer’s Perspective
09/17/2018 | Bill Acito, Cadence Design Systems
Managing the Challenges of Flex and Rigid-Flex Design
09/12/2018 | Dave Wiens, Mentor, a Siemens Business
Chuck Bauer Discusses the Future of Packaging
09/05/2018 | I-Connect007 Editorial Team
Design :: PCB Industry
Moving From 28 Gbps NRZ to 56 Gbps PAM-4: Is it a Free Lunch?
The usual way of signaling through PCB interconnects is a two-level pulse, an encoding of 1s and 0s or bits, named NRZ (non-return-to-zero) or PAM-2 line code type. Increasing the data rate with the NRZ code type presents some obstacles. For a 28 Gbps NRZ signal, the bit time is about 35.7 ps with the main spectral lobe below 28 GHz. For a 56 Gbps NRZ signal, the bit time is about 17. 86 ps, with the main spectral lobe below 56 GHz. One can feel the problem already: Getting PCB interconnect analysis and measurements up to 56 GHz and beyond is very challenging, to say the least.
In With the New at Cadence
The next generation of PCB designers is coming—slowly, but surely. What will this new group of designers mean for EDA vendors like Cadence Design Systems? Andy Shaughnessy recently interviewed Dan Fernsebner, product marketing group director and a veteran EDA guy, and Bryan LaPointe, lead product engineer and representative of the younger generation. They discussed the next generation of PCB designers, some of the best ways to draw smart young people into this industry, and why the PCB designers of the future may need to have a college degree just to get an interview.
Advanced Stackup Planning with Impedance, Delay and Loss Validation
A typical PCB design usually starts with the material selection and stackup definition—the stackup planning or design exploration stage. How reliable are the data provided by the material vendors and PCB manufacturers? Can we use these data to predict trace width and spacing for the target trace impedance or to calculate delays or evaluate the loss budget?
Susy Webb: Training the New Generation of Designers
For years, I’ve been running into Susy Webb at PCB West, where one of the classes she teaches is PCB design basics. I always ask Susy about the class, especially the attendees’ backgrounds. Over the years, her class has begun drawing more and more degreed engineers, with fewer “traditional” PCB designers attending. I asked Susy to discuss the next generation of PCB designers, some of the trends she’s seeing among new PCB designers, and the need for designers to take charge of their own design training, whether their management agrees or not.
Thermal Management Materials: Easing the Decision-Making Process
There are many different types of thermally conductive materials, and choosing between them will be dictated by production requirements and application design, as well as critical performance factors that must be achieved.
CPCA 2018 Seminar Overview
I had the good fortune to speak at a seminar sponsored by the CPCA and organized by the China Team of I-Connect007 in Shanghai. This full-day seminar was on one of today’s hot topics, “Automation in PCB Manufacturing.”
3D Convergence of Multiboard PCB and IC Packaging Design
A new generation of 3D multiboard product-level design tools offer major improvements by managing multiboard placement in both 2D and 3D, and enabling co-design of the chip, package and board in a single environment. Multiboard design makes it possible to create and validate a design with any combination of system-on-chips (SOCs), packages, and PCBs as a complete system.
Sensible Design: Protecting PCBs from Harsh, Challenging Environments
Think very carefully about the sort of environment your PCB is likely to encounter. It is easy to over-engineer a product so that it will survive the very worst of conditions, but worst conditions may only be fleeting or transient. Therefore, a resin solution with a lower temperature performance specification will often cope. Take temperature extremes, for example. Your application may experience occasional temperature spikes of up to 180°C, which you might feel deserves treatment with a special resin.
Excerpt: The Printed Circuit Designer’s Guide to…Flex and Rigid-Flex Fundamentals
The design process is arguably the most important part of the flex circuit procurement process. The decisions made in the design process will have a lasting impact, for better or worse, throughout the manufacturing cycle. In advance of providing important details about the actual construction of the flex circuit, it is of value to provide some sort of understanding of the expected use environment for the finished product.
Making the Most of PCB Materials for 5G Microwave and mmWave Amps
Ready or not, 5G is coming, and it will require the right circuit materials for many different types of high-frequency circuits, including power amplifiers. 5G represents the latest and greatest in wireless technology, and it will be challenging to design and fabricate, starting with the circuit board materials, because it will operate across many different frequencies, such as 6 GHz and below, as well as at millimeter-wave frequencies (typically 30 GHz and above).
Experts Discussion: What Does 5G Mean to Materials and EDA Tools?
Whether we’re ready for it or not, 5G technology is coming. We decided to speak with John Hendricks, market segment manager for wireless infrastructure at Rogers Corporation, and Ben Jordan, director of product and persona marketing for Altium, about the challenges related to 5G and what this means for PCB designers and fabricators.
The Survey Said: Industry Optimistic After Strong 2017
During recent trade shows and conferences, we spoke with a variety of fabricators and assembly providers. They had one thing in common: Every company achieved strong growth in 2017, and shared a positive outlook about the future. This year, the industry is optimistic, driven by positive economic outlook, growing customer demand, and new technologies and vertical markets, among others.
Geeking Out at Geek-A-Palooza MSP 2018
Kiersten Rohde, I-Connect007 editor, covers Geek-A-Palooza MSP 2018. Geek-A-Palooza "is a different kind of gathering that combines networking with a fun, relaxing atmosphere." This event provided an opportunity for local electronics geeks from every industry segment to gather for a professional social event that included great music, food, drinks, games, raffle prizes, and booths.
EDADOC: A Driving Force in China's Automotive Electronics Design
EDADOC is one of the biggest providers of PCB design and manufacturing services in China, with a long history in automotive electronics design and manufacturing. China Editor Edy Yu recently conducted an email interview with EDADOC R&D Technical Research Manager William Zhou and Brand Planning Specialist Wen Ling, who collaborated on their answers. We discussed the challenges related to designing and fabricating automotive PCBs, the opportunities in this segment, and the trends they see in the market for autonomous and electric vehicles.
Expert Discussion: Dan Feinberg on Automotive Electronics
A fixture at the Consumer Electronics Show, Dan Feinberg has been covering autonomous, hybrid and electric vehicles for years, along with the rapid growth of high-tech electronic gadgetry in traditional vehicles. In this freewheeling expert discussion, Dan spoke with Barry Matties, Patty Goldman, and Happy Holden about the future of auto electronics and what it all means to the PCB industry.
Porsche Engineering…by Design
Thomas Wischnack of Porsche Engineering is currently designing the high-power charging infrastructure that will go inside the next generation of automobiles. Thomas was a keynote speaker at AltiumLive 2017 in Munich, Germany. Barry Matties met with him to learn more about Porsche’s hardware and circuit development and what Porsche does to continually bring new designers into the fold.
Martin Cotton Discusses Ventec’s New Book and Low-Loss Materials
During DesignCon 2018, Andy Shaughnessy sat down for an interview with Martin Cotton, director of OEM projects for Ventec. Martin was a PCB designer for years, so he has experience on both sides of the desk. They discussed Ventec’s reasons for coming to DesignCon, their expansion into low-loss materials, and Ventec’s new I-Connect007 book, The Printed Circuit Designer’s Guide to Thermal Management with Insulated Metal Substrates.
Julie Ellis: TTM’s Interface Between Designer and Fabricator
As a field application engineer for TTM, Julie Ellis sees the problems that can occur between circuit board designers and manufacturers. Barry Matties spoke with Julie at the AltiumLive event in Munich about the age-old problem of throwing designs “over the wall,” the trend towards HDI, and what advice she would give new designers.
South African Electronics Industry Going Strong
EDA Technologies is a South African company that offers PCB design engineering services, mainly for the domestic electronics market, which makes up a surprising 12.5% of South Africa’s GDP. Barry Matties recently spoke to founder Nechan Naicker about the benefits of outsourcing to South Africa, the market segments they service there, and any advice he had to offer from his 20+ years in the industry.
Bridging the Customer-Supplier Gap
For the February issue of Design007 Magazine, we interviewed Nolan Johnson of Sunstone Circuits, and Dan Beaulieu of DB Management—our regular columnist—on the topics of knowing your customers, the challenges in dealing with customers, and providing excellent customer satisfaction.
MakeHarvard 2018: The Super Bowl of Makeathons
The inaugural MakeHarvard event was everything one would expect from the title, and more. Sunstone Circuits’ Nolan Johnson and Dustin Jablonski served as both mentors and competition judges. Sunstone sponsored a prize for the best feats of reverse engineering and documentation. Sunstone’s reverse engineering competition was one of the most hotly contested. Judging was based on creativity, depth, technical difficulty, usability, scalability, and value to society.
RTW IPC APEX EXPO: Polar Instruments Discusses New Engineer, SpeedStack Upgrades
During IPC APEX EXPO 2018, Polar Instruments' Lupita Maurer and Geoffrey Hazelett sat down with Editor Andy Shaughnessy to discuss upgrades to their SpeedStack tool and Lupita's new position with the company.
Barry Katz Discusses SiSoft's DesignCon Papers and Plans for 2018
SiSoft President and CTO Barry Katz sat down with Editor Andy Shaughnessy to share his thoughts on the company's papers presented during DesignCon 2018, as well as SiSoft's latest products and plans for 2018.
Part 2: EIPC’s 2018 Winter Conference in Lyon, Review of Day 1
We continue with the rest of Pete Starkey’s report on Day 1 of the EIPC Winter Conference in Lyon, France. Included in this segment are presentations by Ventec, Ericsson, TTM and others, plus photos of their evening tour of Alstom.
Entering—and Enjoying—the Industry
I was recently given the opportunity to write an article for our publication. Being somewhat new to this industry, I figured it would be a good idea to write an introduction on how I got into electronics—specifically the part most people my age don’t give thought to.
EMA Cloud Lined with Capability
Editor Kelly Dack speaks with EMA Design Automation Marketing Manager Chris Banton about the company's new free cloud-based OrCAD schematic capture tool, OrCAD's design constraint manager, and the Sigrity electrical rule checker.
APCT’s Cartel Acquisition Adds Capacity, Technology and Certifications
APCT recently acquired Cartel Electronics and its affiliate, flex and rigid-flex maker Cirtech. During DesignCon 2018, I spoke with APCT President and CEO Steve Robinson about what this acquisition means for the San Jose-based fabricator.
Nano Dimension’s 3D Printing: Prototypes at the Push of a Button?
SICK AG is a global manufacturer of sensors and sensor solutions for industrial applications, with headquarters located in Waldkirch, Germany. After a demo of Nano Dimension’s new 3D printing machine at productronica, Barry Matties met with SICK’s Danny Wernet to discuss its pros and cons and get his overall impression of the technology. Are 3D prototypes really as simple as feeding in a Gerber file and pushing a button?
PCB Cooling Strategies, Part 2
In many PCB designs, component placement plays a decisive role in PCB cooling. But for some boards with areas of high heat and high current, the designer may have to utilize heat sinks, fans, and/or water cooling technology. There are a variety of cooling and heat dissipation options available now, but thermal management research still has a long way to go.
PCB Cooling Strategies, Part 1
With the development of communication and IT industries and the ever-increasing demand for information analysis, many chip makers have racked their brains trying to provide customers with better technology, such as increased computing power and storage capacity of chips as well as diversifying their product offerings.
Dr. Johannes Adam Gets Hot on Thermal Management
Thermal management expert Johannes Adam, PhD, was kind enough to take the train from his home in Leimen, Germany to meet with me during productronica in Munich. He is the creator of TRM (Thermal Risk Management) software and contributor, with Douglas G. Brooks, of "PCB Trace and Via Currents and Temperatures: The Complete Analysis, 2nd Edition." He’s also working on his own book on thermal management. Johannes sat down for an interview, and I asked him to share his views on the current state of thermal management for PCBs, and what the industry can do to put the spotlight on what’s hot in PCBs.
That’s Hot: Ventec’s Goodwin on Thermal Management
IPC’s fall committee meetings were held in conjunction with SMTA International, as has been the case for several years now. Patty Goldman sat in on some subcommittee meetings, including one on laminates, where she met up with Ventec COO Mark Goodwin for a discussion on thermal management from a laminate supplier’s perspective.
Heat Transfer and Thermal Conductivity: The Facts
In my first two columns, I presented a broad introduction to the subject of thermal management of electronic circuits. This month I’m taking a closer look at thermal interface materials—how they can be applied to achieve efficient heat transfer, and the significance of bulk thermal conductivity in relation to heat transfer and thermal resistance.
HDI PCBs: Make the Right Choice from Design to Volume
Modern electronic products are expected to offer evermore advanced functions, while the products themselves are becoming increasingly smaller. There are two key factors for the successful production of HDI PCBs: first, making the right choices at the design stage, and then carefully choosing the factory that can support the specific technical demands of the project. NCAB Group COO Chris Nutall explains.
Who Really Owns the PCB Layout?
In order to understand the current climate, we have to look at the division of labor that took place in electronic design about 40 years ago. The labor was divided into two processes, with the first being the design itself. This process was (and still is) owned by the electrical engineers. Though circuit design has changed, the methods for representing the circuit have not. Paul Taubman of Nine Dot Connects explains.
Nancy Jaster Brings Manufacturing, Design Background to Designers Council
Nancy Jaster was recently named the head of the IPC Designers Council. At the recent AltiumLive 2017 event, I spoke with Nancy about her unique background in both design and manufacturing, and how she hopes to use that experience and mindset to revitalize the Designers Council going forward, particularly with the International and student chapters. We also discussed her plans to bring more young people, particularly women, into the industry.
Video from productronica 2017: Karel Tavernier on Ucamco's New Communic8tor
European Editor Pete Starkey and Ucamco Managing Director Karel Tavernier discuss Ucamco’s cloud-based Communic8tor platform which facilitates two-way communication between the CAM engineer and the PCB designer, or any other party involved in the manufacturing process. This gives real-time access to image data and annotations, enabling queries to be resolved, changes to be approved, and a full communications history to be maintained.
The PCB Norsemen: Industry 4.0, AI and CircuitData
As automation works its way onto the shop floors, it still struggles to replace humans in the supporting roles, such as designers, purchasers, brokers, and back-office staff. Where automation on the shop floor replaces humans in doing repetitive manual tasks, the supporting roles (at least some of them) require intelligence to understand and utilise information.
AltiumLive Summit—Munich, Germany, Part 2
Pete Starkey continues with his review of the AltiumLive PCB Design Summit held recently in Munich, Germany. The second day commenced with a new product launch. “Working together is hard” it read on the screen. Statistics indicated that 33% of new products were late getting to market, of which 28% were late due to insufficient collaboration, and up to 50% of potential revenue could be lost through being late to market. Then the screen read “NEXUS makes it easy!”
Polar Instruments’ Martyn Gaudion Discusses Tools and Books
Polar Instruments has pretty been busy lately. In the last year, Managing Director Martyn Gaudion has written two books for I-Connect007, and the company has been working to upgrade its tools, especially library functionality. I met with Martyn at PCB West. We discussed Polar’s newest tool updates, Martyn’s new side job as an author of technical books, and the continuing growth of the EDA segment, including among young people.
Altium Designer 18 Introduced at AltiumLive 2017
At the recent AltiumLive 2017 event in San Diego, I sat down for an interview with Dan Fernsebner, Altium’s global head of technical marketing. Dan discussed the upcoming release of Altium Designer 18, as well as the company’s corporate responsibility for giving back to the industry and bringing more young people into EDA. The event featured speakers such as Happy Holden, Dan Beeker, Charles Pfeil, and Tara Dunn, as well as a robot team competition.
Full Coverage of AltiumLive 2017
Altium recently conducted its first-ever users conference, AltiumLive 2017: Annual PCB Design Summit, at the Hilton Resort and Spa in San Diego. Speakers included Dan Beeker of NXP Semiconductors, Max Seeley of 3M Corporate R&D, Tara Dunn of OMNI PCB, Susy Webb of Fairfield Nodal, Charles Pfeil of Altium, and our own Happy Holden. This conference drew hundreds of PCB designers, and included a robot design challenge and battle. If you couldn’t make it, don’t worry. We shot a variety of video and still photos.
Whose Fault is That Bad Board?
Years ago, I held a position in an EMS company where projects were analysed before manufacturing. We found that even some of the best and most innovative circuits could not be manufactured. Why? Because the PCB designer, an electronic engineer, was not acquainted with the fabrication process. He had no idea about technological requirements necessary for electronic production. I know another designer who learned, finally, the importance of the thermal relief pad for heat restriction during reflow for a good soldering. His response? “Oh, was that what they were for? And to think I worked so much to remove them!”
Resins: Cutting Through the Technical Jargon
This month, I’m going to cut through some of the more heavy-going tech-speak, taking a few of my customers’ more frequently asked questions about resins to try to help you refine your selection process. There’s a lot of ground to cover, but for the purposes of this column, let’s concentrate on the PCB’s operating environment, caring for the components that are to be encapsulated, and the special needs of applications like LED lighting and RF systems.
New Challenges Facing Mil/Aero Segment
For this month's issue, we invited a sampling of professionals whose experience centers on the electronics industry in the military and aerospace world, including experts from design, PCB manufacturing, and the assembly arena to sit down with us for a frank discussion. Our discussion centered on the challenges associated with military work, including the new regulatory requirements for cybersecurity, dealing with leaded vs. lead-free components, and the differences and similarities with the commercial world.
Stephen V. Chavez Talks Mil/Aero PCB Design
Stephen V. Chavez, CID+, is the lead PCB designer for the Electronic Systems Center division of UTC Aerospace Systems (UTAS), a military contractor that builds all manner of cutting-edge tools for the American warfigher. He’s been designing military and aerospace PCBs for decades, and he’s a veteran of the United States Marine Corps. I caught up with Steph and asked for his thoughts on designing PCBs for the military and aerospace markets.
Orange Co. Designers Council Meeting Focuses on Embedded Passives
On July 19, the Orange County Chapter of the IPC Designer’s Council hosted a lunch-and-learn meeting in Tustin to discuss the benefits of embedded passives. Approximately 40 people were in attendance, which was lighter turnout than usual, most likely because of summer vacations. But the crowd was an enthusiastic one, as usual. The first speaker was Bruce Mahler of Ohmega Technologies, followed by Jin Hyun-Hwang of Dupont.
Trilogy Circuits: Mil/Aero Demands Technological, Regulatory Expertise
In the 16 years since its founding, Trilogy Circuits has become one of the go-to companies for mil/aero PCB design and manufacturing. I spoke with Charlie Capers, president and founder of the Richardson, Texas firm, about how he keeps ahead of the game. As he explains, succeeding with mil/aero PCB work requires not only mastery of the technological side, but of the regulations and certifications as well.
PCB Designers Notebook: Embedding Components, Part 2
Technology and processes for embedding capacitor and inductor elements rely on several unique methodologies. Regarding providing capacitor functions, IPC-4821 defines two methodologies for forming capacitor elements within the PCB structure: laminate-based (copper-dielectric-copper) or planar process and non-laminate process using deposited dielectric materials.
Performance Evaluation of Thin-Film Embedded Resistors
Thin-film microstrip circuits have been widely applied in microwave communications, electronic countermeasures (ECM), and aerospace applications, etc. When manufacturing thin-film ICs, it is very important to apply deposited thin-film resistor material to fabricate high-accuracy and highly stable thin-film embedded resistors. Thin-film ICs call for thin-film resistors that meet stringent requirements.
Launching a New PCB Design Curriculum in Serbia
Let me share with you an experience that I remember from my college days. When I was a student, I had a professor who was too proud of the fact that she was an academic. “You don’t need to know how to manually solder electrical parts or how to design printed circuit boards,” she lectured. “It is important that you understand the formula for charge carrier currents in a p-n junction.” I started working as an R&D engineer for a Swiss company that developed and manufactured instruments for measuring magnetic fields and electrical currents. And nobody ever asked me about charge carriers in p-n junctions.
Must Work Well on a Team; CID a Bonus
Throughout my decades-long career in PCB design, I have been fortunate. I’ve only had to search for a job out of desperation once. I had no idea my IPC Certified Interconnect Designer credentials would come in handy when I hit the pavement. It also helped that I am known to "work well on a team." It turns out that being able to play well with others is a real plus in the PCB design community.
Sensible Design: Casting a Spotlight on Resin Applications
Over the last few columns, I’ve given readers pointers on virtually every aspect of potting and encapsulation resins, ranging from their formulations and special properties to their applications, benefits and limitations. It’s probably high time, therefore, to take a step back from the do's and don’ts and focus instead on how these resins are bringing very real benefits to practical electronic and electrical engineering applications. A good starting point is to look at the special requirements of an industry that is enjoying explosive growth: LED lighting.
Tom Hausherr Discusses PCB Libraries’ BOM Builder Service
PCB Libraries CEO Tom Hausherr and Editor Kelly Dack discuss PCB Libraries’ new BOM Builder service during IPC APEX EXPO. Equipped with the new LEAP technology, the BOM Builder can potentially save PCB designers days or weeks of time normally spent turning a BOM into a CAD library.
Exciting New Technology: Thermal Risk Management
Two years ago I entered into a collaboration with Dr. Johannes Adam, from Leimen Germany. Johannes has written a software simulation tool called Thermal Risk Management (TRM). We used it to look at the thermal characteristics of PCB traces under a variety of conditions, and it is hard for me to contain my excitement and enthusiasm for what it does and what we learned about traces using it. Our collaboration resulted in the publication of numerous articles and a book. In this article, I’ll talk about some of the capabilities of TRM that really caught my attention.
In Deep: The Art and Science of DFM with Gary Ferrari
When the topic of DFM techniques came up, I knew I had to talk with Gary Ferrari of FTG Corp. Gary has been involved with designing and manufacturing PCBs for decades, and he’s the past co-founder and executive director of the IPC Designers Council. I caught up with Gary between Thanksgiving and Christmas, and we conducted the following interview.
Help Wanted! Our 2017 Industry Hiring Survey
This month we conducted an industry survey on plans for hiring during the year. Included here is a summary of the results. We started by simply asking, “Do you plan to hire additional people this year?” More than half of the respondents answered yes while about a third said no—which we take as an optimistic sign that our industry plans to expand in 2017.
True DFM: Taking Control of Your EDA Tool
We PCB designers are doing some truly great things with our layout tools. But we must remember that these tools are so powerful that they will sometimes allow us to design things that can’t be manufactured! We must collaborate with our fabricator and assembly brethren and embrace the best DFM practices, or face the consequences downstream.
IPC Designers Council San Diego Chapter Meeting: Flex Focus Fills the House
A report from the January meeting of the San Diego chapter of the IPC Designers Council. The meeting was hosted by the PCB design bureau San Diego PCB, with the featured guest speaker John Stine of Summit Interconnect. Stine’s presentation focused on flex and rigid-flex DFM, and he offered a variety of helpful design tips to the full house of 30-40 designers in attendance.
Much Ado About Sales and Marketing
We recently surveyed our readers to get a better idea of what company leaders thought about sales and marketing. We sent this survey to several sales leaders; the results were informative, at times surprising, and even a bit disappointing, especially when participants reported that they had no sales and marketing plan at all. Does your company fall into that category?
Sensible Design: Why are Resin Properties So Important?
Last month, I started this series of columns on resins by going back to basics, questioning the core rationale for potting and encapsulation with resins, their fundamental chemistries and how each resin type differs one from the other—indeed, how their individual properties can be exploited to maximise performance under a wide range of environmental conditions. I hope readers found this useful. Of course, when it comes to the choice and applications of resins, there’s a great deal more to discuss.
Leo Lambert Discusses EPTAC’s Evolving Mission
This month we’ve been dealing with challenges related to being a great manager and a great leader. One of the biggest problems a manager faces is training—getting employees trained, and keeping them current on constantly changing technologies. I asked Leo Lambert, VP and CTO of EPTAC, what his thoughts were on the subject of leadership, and more specifically, what strategies EPTAC embraces with regard to training—both initial and ongoing.
SnapEDA: Inspiring Millennials in the PCB Design Community
Natasha Baker, founder of SnapEDA, is part of the new breed of entrepreneurs. She manages a group of millennials who are not much younger than she is. Natasha discusses what it means to be a manager vs. a leader, what motivates millennial engineers, and some of the changes in the world of EDA that managers have to contend with to succeed.
Sensible Design: The Little Guide to Resins
I would like to start this series of columns by going back to basics, questioning the core rationale for potting and encapsulation with resins, their fundamental chemistries and how each resin type differs one from the other—indeed, how their individual properties can be exploited to maximise performance under a wide range of environmental conditions.
Beyond Design: How to Handle the Dreaded Danglers, Part 2
In Part 1, I deliberated on how dangling via stubs distort signals passing through an interconnect and also decrease the usable bandwidth of the signal. This is due to the via stub acting as a transmission line antenna, which has a resonant frequency determined by the quarter wavelength of the structure. The conventional solution to this problem is to back-drill (or control depth drill) the vias to bore out the via stub barrels, so that the via stubs are reduced in length if not completely removed. This month I will look into all the possible solutions.
Prototron Adding a Variety of Services and Certifications
Editor Judy Warner and Prototron Sales Manager Russ Adams discuss Prototron's new capabilities and certifications. The company recently added via fill and limited flex services, and is ready to pull the trigger on AS9100 once the new rev is finalized.
John Cardone on Designing Flex for Spacecraft
If you watched footage of the Mars rover driving all over the red planet, you’re familiar with some of John Cardone’s handiwork. He’s been designing rigid, flex, and rigid-flex circuitry for spacecraft since he joined JPL in the early ‘80s, and he’s worked on some of the more ground-breaking flex circuits along the way. Now John runs his own design service bureau, JMC Design Services, and he continues to design circuitry for things that blast off. I caught up with John recently and asked him to give us the straight scoop on designing boards for spacecraft.
Transline Technology is Bullish on Design Engineers
At the International Microwave Symposium, I met with Chris Savalia, vice president and co-owner of Transline Technology. We discussed the California-based fabricator’s philosophy, the challenges of the RF and microwave markets, and the need to engage with young design engineers now.
Happy’s Essential Skills: Computer-Aided-Manufacturing, Part 1—Automation Protocols
I have addressed automation planning previously in this series, so I hope by now you realize the difference between ‘automation’ and ‘mechanization.’ In printed circuit fabrication and assembly, most of what is advertised is mechanization. But when you get to assembly test, then you begin to see true automated solutions.
The Many Voices Over the Past Year
In line with our "Voices of the Industry" theme this month, we're publishing this handy index of all of the interviews we've conducted over the past year with the movers and shakers, managers, entrepreneurs, and and rank-and-file designers and design engineers. In case you missed them, here's another bite of the apple, alphabetized by interviewee's last name. Enjoy!
Lightning Speed Laminates: Smaller Circuits--Material Properties and Thermal Issues
Coefficient of thermal expansion (CTE) is typically considered for PCB reliability, but it can also have an impact on circuit performance for applications exposed to varying temperatures. Due to CTE, a circuit will change physical dimensions when the temperature changes. If the circuit has small features or tightly coupled features, the physical change of the circuit dimensions can cause a shift in electrical performance.
The Gerber Guide, Chapters 15 and 16
Before sending your Gerber files off to your fabricator, you are often advised to check them using a reputable Gerber viewer such as GC-Prevue. This is excellent advice. Note that this involves more than just verifying that the viewer displays your intended image: It is important that you check too that the file is valid.
Designing for Profitability: Don’t Over-Materialize
John Bushie, applications engineering manager at American Standard Circuits, spoke with Barry Matties recently about how designers can avoid over-materializing. He also outlined the benefits of designing for profitability.
Making Digital and Analog “Play Nice” at Peavey
Most guitarists have owned a Peavey Electronics amplifier or instrument at some point in their lives. Peavey originally drew accolades for their line-up of high-quality, budget-friendly products. Now the company also develops high-end instruments, amps, and live sound equipment. Peavey was also the last major American musical equipment maker to have product manufactured overseas. I met with Tom Stuckman, an electrical engineer at Peavey, during NAMM and asked him about the technical challenges he faces and what it’s like working at Peavey.
The Importance of Design for Profit (DFP)
In this interview, Interconnect Design Solutions’ Mike Brown and I took a few minutes during the recent Geek-A-Palooza event to discuss the importance of material selection and designing for profitability, how automation affects the design process, and the future of the design community.
Beyond Design: The Case for Artificial Intelligence in EDA Tools
There has been a lot of activity in the field of artificial intelligence recently, with such developments as voice recognition, unmanned autonomous vehicles and data mining to list a few. But how could AI possibly influence the PCB design process? This month, Barry Olney will take a look at the endless possibilities.
Tim’s Takeaways: The Basics of Hybrid Design, Part 3
The world of hybrid design is growing, and we have lots of hybrid-specific functionality built into our software that helps designers meet and conquer the unique hybrid design requirements that they are faced with. And yet many designers out there (and I used to be one of them) have no idea what is meant when people start talking about hybrid design.
Romanian Electronics Industry Celebrates 25th Anniversary of TIE
The high point of the Romanian TIE event was a competition among the students to design and layout a circuit for a specific product meeting to the maximum extent possible a long list of design and product requirements. The students had four hours to deliver a design which was then evaluated by a team comprised of a university instructor and a seasoned industry engineer.
PADS Paper: 10 Things to Know about Thermal Design
As designs get smaller, power densities at all packaging levels increase dramatically. Removing heat is critical to the operation and long-term reliability of electronics, and component temperatures within specification are the universal criteria used to determine the acceptability of a design. This PADS paper discusses 10 things designers need to know about thermal design.
Designers Notebook: Flexible and Rigid-Flex Circuit Design Principles, Part 6
The designer is generally under pressure to release the documentation and get the flexible circuit into production. There is, however, a great deal at risk. Setting up for medium-to-high volume manufacturing requires significant physical and monetary resources. To avoid potential heat from management, the designer must insist on prototyping the product and a thorough design review prior to release.
Cadence Paper: Automating Inter-Layer In-Design Checks in Rigid-Flex PCBs
Flexible PCBs make it possible to create a variety of products that require small, lightweight form factors. As flexible PCB fabrication technology has matured, new design challenges have emerged. This paper discusses some of the key challenges and introduces a new PCB design approach that enhances productivity through in-design inter-layer checks.
The Partnership: Design Engineers and PCB Designers
Randy Faucette is founder, president and director of engineering at Better Boards Inc. in Cary, North Carolina. I asked Randy to talk about some of the occasional tension between PCB designers and design engineers, and what he thinks can be done to help open the lines of communication.
Design Strategies for Success—and Profit
In today’s economic environment, making money on a project is getting more and more challenging. Those years when businesses like mine were practically printing money are long gone. If you are under 30 years old, you probably do not have this point of reference; it’s been one downturn after another for your entire adult life. But for us older folks, times were really good back then. So, what happened? You happened, as well as a million others like you. In other words, the market is a little cramped now and much more competitive, which dilutes our profit per project.
Sunstone Circuits R&D: 3D Printing Great for Prototyping
We’ve been hearing a lot about 3D printing for the past few years. But where does 3D printing fit in with traditional rigid circuit board development? Sunstone Circuits recently completed a project that focused on that very question. Sunstone Product Manager Nolan Johnson explains why 3D printing is a viable option when it comes to jigs and parts of the support infrastructure that are needed when prototyping today’s emerging technologies.
Brooks' Bits: How Many Vias Does It Take To…?
During 2015, I enjoyed a very productive collaboration with Dr. Johannes Adam, from Leimen, Germany. This resulted in several papers, but one in particular is relevant for this column, “Via Currents and Temperatures.” In that paper, we used a simulation tool, thermal risk management, developed by Dr. Adam, to simulate current flowing through a via and then determine the temperature of the via. Read on to find out how our results contradicted conventional wisdom.
Beyond Design: The Need for Speed—Strategies for Design Efficiency
Years of experience with one EDA tool obviously develops efficiency, whether the tool be high-end feature-packed or basic entry-level. And one becomes accustomed to the intricacies of all the good and bad features of their PCB design tool. However, there comes a time when one should really consider a change for the better to incorporate the latest methodologies. This month, I will look at productivity issues that impede the PCB design process.
Designers Notebook: Flexible and Rigid-Flex Circuit Design Principles, Part 5
The outline profile of the flexible circuit is seldom uniform. One of the primary advantages of the flexible design is that the outline can be sculpted to fit into very oblique shapes. This month, Vern Solberg focuses on outline planning, physical reinforcement, and accommodating bends and folds in flexible and rigid-flex circuits.
Tim's Takeaways: The Principles of Hybrid Design, Part 1
What exactly is a hybrid design? We are seeing more and more of our customers exploring the world of hybrid design, and we are getting new customers for whom hybrid design is their sole focus. The world of hybrid design is growing and we have lots of hybrid-specific functionality built into our software that helps designers conquer the unique hybrid design requirements.
The Bare (Board) Truth: The Top 10 Ways Designers Can Increase Profits
So, can you truly increase profitability through PCB design practices? Prototron's Mark Thompson believes you can. And it starts with a philosophy that embraces DFM techniques. Then you must be ready for the initial release to a fabricator by ensuring that you are communicating all of your specifications and needs clearly to the fabrication house so that you get an accurate quote. Let’s dive in, starting with Number 10 and working our way to the most important way a designer can increase company profits.
IPC APEX EXPO: Isola Introduces New Products, Increases R&D
Ed Kelley, VP of global technology, sits down with Guest Editor Dan Beaulieu at IPC APEX EXPO to discuss the company's plans for the future. The company is launching new low-loss laminates and increasing its R&D activities around the globe. He also explains why Isola often works with designers at OEMs.
IPC APEX EXPO: Electrolube to Educate PCB Designers on Coatings
Phil Kinner, technical director of coatings for Electrolube, discusses a paper on condensation testing that he presented at IPC APEX EXPO, and his plans to educate PCB designers about conformal coatings to help them avoid problems during manufacturing.
Designers Notebook: Flexible and Rigid-Flex Circuit Design Principles, Part 4
All of the design rules for the glass reinforced-portion of the board (land pattern geometry for mounting surface mount devices, solder mask and the like) are now well-established. One unique facet of fabricating the rigid-flex product is how the flexible portion of the circuit is incorporated with the rigid portion of the circuit. As a general rule for multilayer PCB design, furnish a balanced structure by building up the circuit layers in pairs (4, 6, 8 and so on).
IPC APEX EXPO: Glenn Oliver on His IPC 'Best Paper' on High-Frequency Materials
Glenn Oliver of DuPont discusses his award-winning paper, “Round Robin of High-Frequency Test Methods by IPC-D24C Task Group." Co-authors include Jonathan Weldon of DuPont, John Andresakis of Park Electrochemical, Chudy Nwachukwu of Isola, John Coonrod of Rogers Corporation, David L. Wynants of Taconic Advanced Dielectric Division, and Don DeGroot of Connected Community Networks. The paper looks at high-frequency offerings from a variety of materials providers.
Beyond Design: Faster than a Speeding Bullet
In optical communications, electrons don’t carry the signal—photons do. And we all know that photons travel at the speed of light. So surely, optical fibers must transmit information much faster than copper wires or traces on a multilayer PCB? Actually, photons and electrons transmit data at the same speed. The limiting factor is the relative permittivity (dielectric constant) of the medium in which the signal propagates.
Enhancing Thermal Performance of CSP Integrated Circuits
In order to meet size and weight requirements, constraints of portable electronic designs often force PCB designers to reduce the size of components and PCB real estate area. To meet these demands, the use of CSP packages to shrink the PCB area needed is a common change in designs. As a result of the reduction of total PCB area, the available options to move heat and route high-power PCB traces is also reduced. Furthermore, the thermal performance cannot be matched when a QFN is compared to an equivalent CSP package.
Designers Notebook: Flex and Rigid-Flex Circuit Design Principles, Part 2
In this installment of "Designers Notebook," Vern Solberg discusses supplier assessment, planning of the flexible circuit outline, and various circuit routing principles. Communication between designer and fabricator is paramount, as well as an understanding of IPC-2223, which sets the specific requirements for the design of flex circuits.
Justifying the Need to Outsource Design Work
Mehul Dave and H.D. Shreenivasa of Entelechy Global discuss the many benefits of outsourcing and why it should not be thought of as a four-letter word. They also talk about the huge gap between design and manufacturing, and how their company can help customers address that issue.
American Standard Circuits: Leading the Way in Medical Electronics
When it comes to innovative fabricators, American Standard Circuits is always at the front of the pack. Naturally, when Editor Andy Shaughnessy asked me to interview a fabricator about PCBs for the medical market, ASC was the one company that immediately came to mind. I spoke with CEO Anaya Vardya about fabricating medical PCBs, the medical electronics market, and the future of this fast-growing segment.
Fabrication Drawings and Electrical Test— Reading the Fine Print
When a new PCB design is born, designers envision what the product will provide when completed. Whether the product is for the consumer, aerospace, military, medical or countless other markets, the designers—or more likely, the customers—expect certain deliverables on the commodity they wish to purchase.
Innovative Circuits Sees Healthy Medical Market
Medical electronics is one of the fastest growing segments of our industry. Alpharetta, Georgia-based Innovative Circuits is at the forefront of fabricating medical PCBs, both flex and rigid. I asked Innovative Business Development Manager Amir Davoud to give us a solid diagnosis of the world of medical PCBs.
Beyond Design: Plane Crazy, Part 2
In my recent four-part series on stackup planning, I described the best configurations for various stackup requirements. But I did not have the opportunity to delve into the use of planar capacitance to reduce AC impedance at frequencies above 1GHz, which is the region wherein bypass and decoupling capacitors dramatically lose their impact. In this column, I will flesh out this topic, and consider the effects of plane resonance on the power distribution network (PDN).
IPC Designers Council Viewpoint: Mike Creeden
When covering the IPC Designers Council, one quickly learns that it’s the volunteers who make the train run on time. San Diego PCB CEO Mike Creeden, CID+, is one such volunteer, and as a member of the Designers Council’s Executive Board, he was a must-have for this issue. I tracked him down and asked him to give us a rundown of his involvement with the DC, and to explain why designers might want to get involved with their local DC chapters.
McCurdy: How to Build a Successful IPC Designers Council Chapter
When Scott McCurdy made his transition from PCB fabrication to a PCB layout focus about 13 years ago, he accepted an invitation to attend our local IPC Designer’s Council. Shortly after, he was recruited to serve on the group’s steering committee. At that time, 20–25 people were regularly attending the meetings. When the chapter president moved, he asked Scott to take his place. Now, Orange County chapter meetings often draw close to 100 attendees.
IPC Designers Council Viewpoint: Rick Hartley
Rick Hartley has been in involved in PCB design and design education for decades, so it’s no surprise that he started working with the IPC Designers Council early on. Now retired from his day job at L-3, Rick still teaches PCB design and shows no sign of slowing down. I asked him to discuss his work with the Designers Council, and what the group means to the design community.
The Shaughnessy Report: Are You Drowning in Data?
Data management was so much simpler during the days of Mylar and Bishop Graphics tape. Data was handwritten. All you had to do was keep track of your paperwork and you were golden. Now, you’re all much more productive, but you have data coming out of your ears; slowly but surely, incrementally, data has become much more complicated. How do designers and engineers wind up managing all of this data? With kluged-together processes and software tools, and the occasional handwritten notes.
DownStream Takes on Data Documentation Management
Most designers will tell you that, as much as they enjoy laying out boards, they dislike the final data documentation step, which often involves various formats, including handwritten notes. Enter DownStream Technologies, a company founded 14 years ago to address the challenges related to post-processing the design. Senior Product Marketing Manager Mark Gallant recently discussed the company’s efforts to take the pain out of data documentation, even as data becomes more complex.
Good in, Good out: Bay Area Circuits Discusses Data Strategies
A lot of companies talk about the importance of good data management, but for some firms, this amounts to little more than lip service. Then there are companies like fabricator Bay Area Circuits. I recently sat down with Bay Area Circuits President Stephen Garcia and COO Brian Paper to discuss how automating and upgrading their data systems has significantly cut down overall process time, as well as their drive to educate young PCB designers and actively promote the industry to the emerging electronics industry workforce.
The Gerber Guide, Chapter 3: The PCB Profile
The profile defines a simple region in the 2D plane. The proper way to do this is to specify a closed contour: The inside of the contour is the PCB, and the outside is not. It is that simple. Note that such a simple region is solid, without holes. By definition then, a profile cannot have holes intentionally placed within it. These are superfluous and represent an unnecessary and complicated duplication given that drill holes are well defined in the drill/rout file. One can view cut-outs in a PCB as still part of the PCB, just as much as the drill holes are.
Beyond Design: Stackup Planning, Part 4
In this final part of the Stackup Planning series, I will look at 10-plus layer counts. The methodology I have set out in previous columns can be used to construct higher layer-count boards. In general, these boards contain more planes and therefore the issues associated with split power planes can usually be avoided. Also, 10-plus layers require very thin dielectrics in order to reduce the total board thickness. This naturally provides tight coupling between adjacent signal and plane layers reducing crosstalk and electromagnetic emissions.
Speeding up the Design Cycle: 10 Things to Remember
Many people understand the value of a PCB, but do not understand the best way to interact with PCB manufacturers. Poor planning and communication with fabricators slows down the design cycle and increases overall costs for your project. In this column, Mark Thompson streamline the design cycle through fabrication. Following my tips will minimize the need for future revisions and ensure you get quality boards on time.
Lightning Speed Laminates: Impact of Final Plated Finish on PCB Loss
A variety of plated finishes are used in the PCB industry. Depending on the circuit construction and other variables, the plated finish can cause an increase in PCB insertion loss. The plated finish used on the outer ground planes of a stripline circuit have minimal or no impact on insertion loss. However, microstrip or grounded coplanar waveguide circuits, which are common on the outer layers of multilayer high-frequency PCBs, can be impacted by the plated finish for increasing the insertion loss.
Accelerating the PCB Design Cycle
An area of communications that is often underappreciated, but has become vitally important to design efficiency, is the dialogue with the PCB fabricator. It’s critical to engage the fabricator very early in the design process to nail down the proper materials and stack-up. With so many options for via structures, it is critical to select the most appropriate structure for the design. Adding blind and/or buried vias as an afterthought can limit their utilization and drive up the printed circuit board cost.
The Material Witness: Nonwoven Aramid Reinforcement is Back
In the 1st century AD, there was significant debate among Jewish theologians as to whether resurrection was possible. PCB designers in the early 21st century have had a similar concern about future availability of 85NT nonwoven aramid laminate and prepreg. The stakes may be somewhat less critical, but the future of a wide variety of programs designed around the properties of Thermount have been hanging in the balance.
Insulectro Hosts Silicon Valley Designers Council Meeting
On October 15, about 25 people gathered for the IPC Designers Council Silicon Valley Chapter meeting at Insulectro's Mountain View facility. Carl Schattke, senior PCB design engineer at Tesla, was the main speaker. His presentation covered a variety of facets of PCB design, from shadowing to the location of component based on weight and surface finishes.
The Shaughnessy Report: Squeezing Seconds Out of the Design Cycle
When you’re designing a board, time is always your enemy. That’s what we learned when we surveyed our readers recently. PCB designers said that time pressure was one of their least favorite parts of the job, and in some cases, they were ready to retire just to avoid design cycle challenges. I imagine that many of you near retirement, and that’s quite a few of you, feel the same way.
The Challenges of Being Competitive in Automotive Electronics Manufacturing
Simple electronics were gradually introduced into automobiles from the earliest times. At first, these were just simple electro-mechanical devices to make cars work without manual effort, such as to start the engine and keep windshields clear. But in this past decade, we have seen the effects of the gradual growth of issues with electronics systems, with recalls caused by safety issues that cost automotive manufacturers millions of dollars. Electronics within an automotive environment today requires a new approach to ensure a higher level of quality perfection.
Top Gear: PADS Professional Road Test
In this column, Barry Olney test drives the newest version of the Mentor Graphics PADS Professional EDA tool. "Based on Xpedition technology, PADS Professional is a major improvement over the previous PADS suite of tools. utilizes xDX Designer as the front-end design entry tool. The latest routing technology is fast, smooth to drive, and hugs the corners well, with all the horsepower you need for the most demanding design."
Leo Lambert on EPTAC's Customized Training Plans
Andy Shaughnessy interviewed Leo Lambert, vice president and technical director of EPTAC, at SMTA International. Leo Lambert, vice president and technical director of EPTAC, explains how the New Hampshire-based company continues to provide customized training and IPC certification offerings, including its IPC Certified Interconnect Designer (CID) and CID+ classes.
The Gerber Guide, Chapter 2
Never mirror or flip layers! All layers must be viewed from the top of the PCB, which means that the text must be readable on the top layer and mirrored on the bottom layer. Alas, sometimes, in a mistaken attempt to be helpful, designers flip layers because they must anyway be mirrored on the photoplotter. This could be helpful in a world where the designer's files are used directly in fabrication, but these data layers are actually input for the CAM system.
Mentor Graphics Helps Bridge Gap Between PCB and RF
Recently, Publisher Barry Matties met with Per Viklund, the director of IC packaging and RF product lines at Mentor Graphics, and Alex Caravajal, business development manager with Mentor. They discussed the challenges facing PCB designers working with RF and microwave technology, and Mentor’s efforts to help reduce the RF design cycle time.
Failure Mode: Hole Wall Pullaway
This column is based on my experience in test reliability of interconnect stress test (IST) coupons. I am addressing HWPA that features moderate to severe outgassing. There may be HWPA due to thermal stressing of the board without any significant outgassing, but this type of HWPA is subtle, and it presents as a dark line between the plating and the dielectric of the hole wall. This type of HWPA is rarely detected.
Beyond Design: Stackup Planning, Part 3
Following on from the first Stackup Planning columns, this month’s Part 3 will look at higher layer-count stackups. The four- and six-layer configurations are not the best choice for high-speed design. In particular, each signal layer should be adjacent to, and closely coupled to, an uninterrupted reference plane, which creates a clear return path and eliminates broadside crosstalk. As the layer count increases, these rules become easier to implement but decisions regarding return current paths become more challenging.
Kelly Dack and Mark Thompson Unite in the War on Failure
There’s been a lot of talk about fighting the war on failure in the PCB industry. But what strategies should our generals follow to prosecute this war? What exactly constitutes a failure in the first place? Is this war even winnable? I recently spoke with longtime designer Kelly Dack and CAM support veteran Mark Thompson of Prototron Circuits about the best battle plans for beating failure, and why designers and manufacturers must team up against this common enemy.
Karel Tavernier: The Gerber Guide
It is possible to fabricate PCBs from the fabrication data sets currently being used—it's being done innumerable times every day. But is it being done in an efficient, reliable, automated and standardized manner? At this moment in time, the honest answer is no, because there is plenty of room for improvement in the way in which PCB fabrication data is currently transferred from design to fabrication.
Supply Chain Challenges and Opportunities
Let’s start by defining exactly what a supply chain is. It’s not a nautical term for an anchor chain, or a dynamic part of a chainsaw that never runs out of chain. No, it’s a key term used in the organization of resources which may form a system between entities. Now this sounds a little closer to something that may be utilized in producing an electronic end-item, in our case, a printed circuit board.
Gary Ferrari Shares His Thoughts on PCB Design and More
Recently, I spoke with Gary Ferrari, director of technical support at Firan Technology Group, about numerous topics related to PCB design. Our conversation ranged from CID training to the need for reaching high school students as a way of introducing more young people to career opportunities in our industry. We also covered strategies for helping customers design and build better product, and keeping designers provided with the most critical part of their supply chain—information.
TTM: Consult Fabricators Early for PCB Designs
Recently, I attended the Designers Council “Lunch and Learn” at Broadcom’s office in Orange County, California. One of the speakers at this event was Julie Ellis, a field applications engineer with TTM Technologies. She sat down with me to discuss her presentation and some of the ways fabricators can assist PCB designers.
A Review of the Opportunities and Processes for Printed Electronics (Part 1)
As microsystems continue to move towards higher speed and microminiaturization, the demands for interconnection are opening up new opportunities for "innovative" interconnects. In the first part of this five-part article series, Happy Holden gives a brief background on printed electronics, as well as presents key technologies that are being employed for PE production.
American Standard Circuits’ Unique Offerings Contribute to Long-term Success
At the recent IMS RF and microwave show in Phoenix, Arizona, Anaya Vardya, CEO of American Standard Circuits, sat down with I-Connect007's Barry Matties to discuss the current market trends, the company's recent equipment investments, and where American Standard Circuits' growth will likely come from.
How to Successfully Purchase PCBs
How do you go about purchasing reliable and durable PCBs at the lowest possible cost? A key success factor is to provide the prospective suppliers with accurate and clear specifications, and to keep a close eye on the quality of the boards once they are in production.
How to Streamline PCB Thermal Design
Thermal issues with a PCB design are mostly determined during the component selection and layout phases. After this point, only remedial actions are possible if components are found to run too hot. John Parry discusses how addressing thermal issues early in PCB design, starting at the system or enclosure level, can help streamline the entire process.
CES 2015: Preview and Predictions
Looking back over the last five years of CES and analyzing predictions and items featured by the large exhibitors, you'd likely assume the 2015 show would feature more advanced 3D TVs, as they were predicted to take over the market...wrong!
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