Warner: Welcome back, Rick. The first time we met, we were ranting about how we both wished more designers would spend some time visiting their board suppliers and learn more about how boards are manufactured. What other pieces of advice would you give to an engineer or PCB designer today?
Hartley: It's interesting you say that. Back in the '77-’78 time frame, when I first became a printed circuit designer, one of the fabricators that our company used sat me and the other printed circuit designer in the company down and said, "We understand that the engineers in the company love you guys because you're both engineers who chose to become printed circuit designers,” and we smiled and nodded knowingly like, "Yes, we're wonderful people, we know that.” Then they looked at us and said, "You guys may understand circuits and may understand how they work, but you know nothing about manufacturing. You people are so clueless, it's amazing. Everything you design is impossible for us to build." My ego fell through the floor. It didn't fall to the floor, it went into the floor! It literally took me a week to recover from that. But once I thought about it, I realized, they're right. I don't know anything about manufacturing. We made a conscious decision as a company to hire Norm Einarson. Anybody reading this interview who is an old-timer will recognize the name and they're smiling right now as they're reading, because Norm was a PCB god back in the day. He was a manufacturer who understood design. He came to our company for a week. Attendance was mandatory for everybody in engineering, EEs included, to sit through this entire week of training. He taught us how we affect manufacturing and how manufacturing affects us.
Warner: What a great and unique opportunity for all of you!
Hartley: It was the best week of training I've ever had in my life. Ever since then, I've subscribed to multiple manufacturing magazines because I want to know what the manufacturing world is doing differently than they did last year, what's new, what's coming. I can't design circuit boards correctly unless I design to the processes they're using.
Warner: I know a lot of fabricators that wish more designers took that proactive approach. It makes perfect sense.
Hartley: It does, doesn't it? And that's one of the things I would say, if you're an EE or a printed circuit designer; if you're involved in any way in the decisions that go into designing the printed circuit boards, you need to understand the manufacturing processes. You need to understand board fabrication, board assembly, and testing, and what impact you have on all three disciplines.
Warner: I couldn't agree more. It resonates with me because I come from the manufacturing and assembly side of the electronics industry. I consistently experienced issues and delays that could have been so easily avoided if we would have just had a conversation before things became problematic.
Hartley: Another suggestion would be for PCB designers and EEs who work together to get closer. Get to know what each other does. Engineers need to understand how complex board design really is because I don't think a lot of them do. They both need to understand each other’s disciplines deeply enough to function well together. If they don’t, then they're in a toss-it-over-the-wall environment where the engineer says, “Here's your schematic, go do your thing.” That doesn't work well-- I learned that years ago. Most of the engineers I worked with at L-3 and in the telecom world, and even going back into the late seventies and eighties, worked well with me and I tried to always work well with them. I guarantee if any of them read this article when it's published, they will be nodding and saying, "Yes, we did work well together." That’s because we understood each other. And that's important.
Warner: Which appears to be rare these days. When they don't work together, does it create some tension between those two disciplines?
Hartley: Of course, it does. It becomes an ‘us and them’ environment, and that's never healthy.
Warner: Absolutely not. So, a third piece of advice, Rick?
Hartley: Don't do anything in the way of printed circuit layout that's stated on an IC application note.
Warner: You said that at IPC APEX this year, which made me laugh!
Hartley: It's true. I start every class I teach with a quote from Lee Ritchey, a quote he made in his class in 1993. When he said it, I giggled, as I thought I was the only one in the world who had that attitude. I was so glad to hear a really knowledgeable guy make that statement. Lee’s quote was, “IC App Notes should be Assumed Wrong until Proven Right.” He is not saying they are wrong, rather that enough of them are wrong that you are wise to NOT assume they are correct. Dan Beeker, a friend and an app engineer at NXP / QualComm, believes that deeply. He tells people in his classes, "When you read a piece of circuit advice in an app note, it’s probably right. But app Engineers typically don't understand board design, and they make statements in app notes that are not based in solid physics, like, split the ground plane into little pieces and put one piece here, another here and one of them over there. Put decoupling in places where it absolutely makes no sense. Don’t use 90 degree corners. They make these statements that are just not based in solid physics. And I'm not saying all app engineers are wrong, I'm saying that many of the app notes that are out there are just very poorly done with regard to circuit board layout advice. Be cautious about what you believe!
Warner: That's funny. I remember you put that quote up at your class and I chuckled. It seems very counterintuitive since we all rely on data sheets.
Hartley: Well, the information in data sheets is generally correct because they give you timing figures, they give you max current draw, and these sorts of things. Those are generally good pieces of data. One thing I wish data sheets would publish is rise and fall time. One of the most important things engineers and designers need to know to make intelligent circuit decisions is the rise and fall time. Truth is, the clock frequency, the frequency at which the clock is driven in a circuit, has very little, if anything, to do with the frequencies where things go wrong. It has almost nothing to do with EMI problems and little to do with signal integrity problems. Signal integrity and EMI problems are related much more to rise and fall time. The problem is, rise and fall time are a bit nebulous. They're not easy to pin down. But if they would at least publish the min and max rise and fall times, the worst-case conditions, so engineers and designers would know what to expect from any given IC when they're doing a layout, when they're designing the circuit and the PC board, and planning for what frequencies are important.
Warner: Why do you think they don’t publish it on data sheets?
Hartley: Because it is hard to pin down.
Warner: Is that due to environmental impacts, or what makes it nebulous?
Hartley: Temperature changes impact rise and fall time, as do loading and other factors. It will either speed up or slow down, depending on conditions. Loss factors in the board also impact rise and fall time. The information is available in IBIS and SPICE models. Models are in ASCII format, easily readable. When you use the model in a simulation tool, like Hyperlynx, for example, that model has to have rise and fall time to accurately determine how transmission lines will behave. So, it's in there, you just have to look for it.
Warner: That's interesting. I didn't know that. Okay, next question: what do you wish EDA tool companies would do differently? Or, what do they do now that either helps or hinders PCB designers today?
Hartley: That's a good question. I think all the EDA tools I've ever used, once I learned them, were fairly powerful. Many years ago, I used a tool called ‘Theda’ from a company named Incases. I found it to be horrendously non-user-friendly. It was also a horrible tool to learn, but once I figured it out, it was quite powerful. I found that to be true of Mentor Board Station as well, hard to learn but powerful.
I found original P-CAD (Master Designer) to be powerful, especially since it was the first PC-based tool, but to me it was not user-friendly. Pads PCB came out in 1985. I found it to be a very user-friendly tool right from the get go. All of these tools, once I learned them, were powerful. The problem, they all have vastly different learning curves and user interfaces. Some of them were designed by people who truly understand what printed circuit designers do, some were designed by programmers who know nothing about printed circuit design. The ones that were designed by programmers typically aren't user-friendly because they simply do not grasp what we need. I just wish they would all step back and ask themselves, "Okay, what could we do to improve the user interface and ease of use of our tool?"
In the 1990's Tango purchased P-CAD, restructured the tool entirely and renamed it Accel. When they were done it functioned more like PADS PCB than like P-CAD Master Designer. It was so user-friendly, the redesign was masterful. When I went to the telecom world, they had Accel. Having never used it, I sat down with the manual and in three days became completely proficient. Eventually, the tool was renamed P-CAD 2001 and later 2003, etc. Many of the features from that tool are in Altium today.
Accel was ridiculously easy to learn. Pads I found to be almost equally that easy. Board Station took me six months and I was still scratching my head. Now Board Station's gone, it has been folded into Xpedition under Mentor's domain. They've done a good job. I like the Mentor tools, I like Altium's tools, I like a lot of the tools that exist today but I wish they would all work on their ease of learning and ease of use. I have never used Cadence tools, so cannot comment.
Warner: Makes a lot of sense. What do you think about licensing models or did that ever impact you since you were working for large OEMs who managed tool acquisition?
Hartley: At L-3, the IT guys took care of all the licensing issues. Before that, I took care of my own licensing. Some of the tools were very easy to fire up and use and their license was very easy to install, but some tools were an absolute nightmare. That's another thing that I think many of them need to work on. I know they're trying to protect their proprietary material. I understand that need. But some of these companies have figured out how to do this with easy to use license structures and others have very complex, hard to use licenses and I just wish those companies would think about it a bit more.
Warner: Good advice. Lastly, I know you have been on the executive board of the IPC Designers Council Committee, so would you talk a little bit about how and when you got involved? Will you also please comment on the value and challenges you see for regional designers councils going forward?
Hartley: Sure. I've been on the IPC DC board since 1996 or ‘97, about 20 years. Gary Ferrari recruited me. Gary and I met in '93 at PCB West and we just hit it off. When they were starting the designer council, I was curious about it and I asked him what it would take to start one in our region and he helped me with the information as did other people from IPC. He was very heavily involved back then and was very helpful. Pete Waddell of UP media (Printed Circuit Design, Fab and Assembly magazine) was also very helpful. Pete offered to send out our initial letter for recruitment of members to everybody within a 100 or so mile radius of Columbus, OH, basically to all the readers he had in that area.
Warner: Doesn’t Pete have a design background?
Hartley: Pete was a designer, yes. The original Designers Council was located in Atlanta. Pete was part of that, so he understood the value and the need. Anyhow, I've been involved for a long time. We had a designer chapter in central and southwest Ohio, starting in about the '93-’94 timeframe. Right around the time, the whole thing was taking off. Our designer council was strong for about 12 years. Our model was different than the ones you guys have in San Diego and in Orange County, we basically learned from each other. We had about 30 to 40 regular members. We met every month for about 12 years. Two of those meetings every year were parties, the other ten meetings of the year were educational, we basically taught each other what we knew. We had people in the group who were manufacturers, EEs, and designers, people from all walks of the business.
For one to two meetings each year we would invite an outside speaker to do a one-day seminar. We charged our members a nominal fee, for that matter, anybody could attend. Non-members paid twice as much. Basically, we would charge everybody some small amount so we could pay the speaker a stipend for their expertise and time. After about 12 years, we just ran out of things to tell each other. Our designer council basically fell to the way side and hasn't been in existence since about 2005.
The advantage of a regional designer council is the chance for people to learn. The chance for people who can't afford to go to PCB West, who can't afford or have the time to go to IPC APEX or go out and buy 100 books like I've done. To be able to go to a meeting once every month or two and learn something that might be valuable to them in their ongoing strife in life as an engineer or as a board designer is the real value of a regional designer council. The education is invaluable.
Warner: I have found the networking to be invaluable over the years as well.
Hartley: To me networking is absolutely essential, it is the key to success. There are a lot of people who want to see more online training. I like online training, don't get me wrong, but I don't think there's any substitute for standing in front of a room and letting them see you and you seeing them. And then comes the networking during and after the training. You are right, the value of networking is massive. My career has benefitted so much from the face-to-face contacts I’ve made, it’s hard to measure the value.
Warner: There is no substitute for face-to-face interaction at industry events. Which, by the way, is how I had the good fortune to meet you, Rick!
Hartley: Exactly--and look where we are today.
Warner: Well, I feel very fortunate to know you and I can’t thank you enough for taking the time to share your illustrious history in PCB design and electrical engineering, as well as your hard-won wisdom on a very complex subject.
Hartley: My pleasure, Judy, happy to do it.
About the Author
My role is to serve as a neutral set of eyes and ears for the design community--and above all to listen intently. As a result, I hope to amplify and empower the voices of today's PCB designer so that what they say will continually shape PCB design software and equip them with the best tools on the planet.More Content by Judy Warner