New Tools Mean More Designer Control for High-Speed PCBs

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In the last hour of the electronica exhibition in Munich, Pete Starkey finally got the opportunity to sit down with Martyn Gaudion, Managing Director of Polar Instruments. They discussed the changing state of PCB design, and how the newest software tools allow PCB designers and engineers to have  more control when designing high-speed PCBs.


Pete Starkey: Martyn, we have tried to get to speak to you several times during the last three days, but your stand has always been under siege from interested visitors. Maybe you could give us some idea of the sort of people who have been coming to see you this week.

Martyn Gaudion: Yes, certainly, Pete. It's good to be back here, and it's good to take a breath from all the visitors we've been seeing this week. Electronica has been very busy. One thing I'd say is that the visitors we have seen this week have often been designers or PCB technologists who are looking to get better control of the specification of their circuit boards.

I think more and more what we'd like to see, or what they would like to see, is the ability to specify PCBs from one, two, or three different suppliers and actually be comfortable that they will get the same PCB back that will meet their specification for each one. In fact, we've met some PCB technologists who've ordered the same PCB twice from the same supplier and has actually received two different products back. So the tools we've been developing help them to get the specifications right.

Starkey: It's interesting you talk about designers, because during my time in PCB manufacturing the designer knew what his layout was, the designer knew what signal carrying characteristics he wanted to achieve, but he then passed that down to the PCB fabricator and the PCB fabricator would use your tools to determine his own stack-up. He would use materials which fitted into his requirements, etc. Effectively he was using the right tools, but he was using them in isolation and doing his own thing. What you're saying now is it's gone up a level.

Gaudion: It has.

Starkey: It's the designer that wants to use the tools to specify the details of the stack-up and the details and the material characteristics before it ever gets to see the PCB fabricator.

Gaudion: Yes, and some designers work in the way you were saying for less critical boards, and that's fine because it keeps the cost down and gives the PCB fabricator maximum flexibility. Other designers who want to have absolute consistency now start to work and specify materials, and we're now having to teach designers about glass styles, resin contents, and get concerned about the things that they could previously completely ignore. We get a superb degree of help from all the material suppliers that are here in force, and we work very closely. We have libraries of all their materials, and those material suppliers work hand-in-hand with Polar to make it easier for OEM designers to specify their PCBs. In fact, when I talk about designers it's often PCB technologists. These guys are often designing the layer stack-up before they have even got to a CAD system. So, what they will do is design a stack-up for PCB for a particular type of technology, and then use our tools to export the stack-up direct into the all the major CAD packages.

Starkey: So they've actually built the board before they lay out the interconnect.

Gaudion: Yes.

Starkey: That’s a very significant step forward.

Gaudion: It is, yes. We've been talking with Karel Tavernier of Ucamco, and Karel was saying to us that some of the formats don't carry the full amount of data needed for the designer to transfer the information to the fabricator. So we're working closely with people who control the formats of data to ensure the stack-up data is good enough to transfer this information.

Starkey: That's really interesting to know. As you say, it's really giving the designer more opportunity to control what the product is going to be, whoever makes it. Provided the buyer places the job with a competent and professional PCB fabricator, the fabricator simply provides a manufacturing service, working to a stack-up and material specification set by the customer. And the customer gets a uniform product wherever it’s sourced.

Gaudion: Exactly.

Starkey: Specifically, Martyn, what sort of technologies are people interested in designing these days?

Gaudion: We've seen a lot of interest in flex-rigid, also called rigid-flex. People are doing more complex things with rigid-flex. In our tools we have certain rules as to how you can and can't design the stack-up, and we have to keep changing this because PCB fabricators are so innovative that things that you couldn't do two years ago you can do now. So we suddenly find out and say, "Well, this is not a very good idea." They say, "Well actually, that's what we're doing now." So we constantly have to update our tools to reflect that people are doing quite different things and putting different materials in places that they didn't used to appear before. We're having to look at making the stack-up design tools more flexible to reflect how people are putting PCBs together.

Starkey: I was going to say, back in the day if it was a design with controlled signal transmission characteristics, we tended to think of it as a rigid board design with conventional and recognizable dielectrics. The flex element throws in a whole new spectrum of material properties and characteristics that you've got to take into account.

Gaudion: It does, and we're seeing some incredible changes there, especially with automotive, where every technology is being thrown in. Take a supposedly simple thing like a car headlamp. We're accustomed to seeing the design incorporate metal-back PCBs for heat dissipation, but now we've got headlamp manufacturers using high-speed design tools, because there's a camera in the headlamp which controls the headlamp pattern, and they've got high speed signalling going on. So instead of it being "this is a board which needs good heat conduction," what they actually need is a combination of good heat conduction, high-speed performance, flex, and low-cost. So everything is thrown into automotive, which means it's very, very challenging from every angle.

Starkey: As you say, not that long ago there wasn't much in the way of electronics in a motorcar. Now the motorcar is built around the electronics. I think a lot of the requirements of the automotive industry are driving the whole of the PCB technology forwards.

Gaudion: We've seen companies that are doing Android apps for detecting children moving around inside cars and all sorts of technology like that, which, as you said, five years ago was unheard of. There's a massive amount of electronics, not only in the self-driving and autonomous cars, but just the general extra information that's involved in driving a car now.

Starkey: Particularly exhibiting here in Germany, you're really at the heart of it.

Gaudion: There's an enormous number of automotive people here, so we're seeing all the European automotive people. But I was at PCB West just a few weeks ago and we were seeing automotive people there as well. Automotive is beginning to be resurgent in the U.S., and also the next generation of communication in vehicles is going up a level in speed, so suddenly there are transmission line challenges on interconnect in the cars as well. That's really quite an interesting area to be working in at the moment.

Starkey: Martyn, already you've mentioned the relationships that you're building with material suppliers and the cooperation you're getting from them, such that they can understand what you're trying to do, and you can understand the characteristics of their materials, so that you can get involved at the very early stages. How are these relationships building?

Gaudion: They're fantastic. Every year they get better and better. As we add more material suppliers into our libraries, they're all coming to us for help and advice. We can learn a lot from them as well, because we're electronics people. We're not chemists, we're not process people. We have a fantastic relationship. Many times we'll visit potential customers together with a material supplier, because the material suppliers are working very hard to help the OEMs to specify the materials into the designs. That's been very rewarding.



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