Interview with Jeff Smoot

Featured Engineer

Jeff Smoot

Jeff Smoot - Vice President of Engineering at CUI Inc

How did you get into electronics/engineering and when did you start?

I kind of got into electronics by accident. I went to Montana State University and got a B.S. in mechanical engineering, so I started my career as a mechanical engineer.

Growing up, I went to what I like to call Engineering Nerd Camp during high school. It involved going to the University of Wyoming where they take you in and expose you to a bunch of different projects and disciplines over the course of about a month. I definitely liked the mechanical side. Any time I touched electrical engineering, whether it was during the camp or during the classes I had to take for my degree, my thoughts were always, “I’m so glad I’m not going to be doing anything with electronics and I’m going to be away from that industry!” When I got done with my circuits class I was like, “Hallelujah! I can sell my book back for 45 dollars and never use or touch it again.” Lo and behold, five or six years later, after working on the mechanical engineering and manufacturing engineering side, an opportunity opened up here at CUI which I worked into, and now I do electrical engineering on a daily basis.

What are some of your favorite hardware and software tools that you use?

Definitely one of my favorite hardware tools, and this is probably due to my mechanical engineering prowess, is the thermal imaging camera. I love using it to take images, because especially with power supplies and electronics in general, you can have a great product and a great design, but so often it comes down to heat and how you get rid of it.

I’m also a pretty big fan of using the Tektronix oscilloscopes we have here in the lab for looking at the waveforms or the voltage levels.

Can you tell us a little bit about CUI and the products it offers?

We have our core business, which includes our components. These are things like speakers, connectors and buzzers. Supplying components like these 22 years ago is where CUI got its start.

We also have our encoder line consisting of optical encoders and our proprietary AMT encoders which use capacitive technology for rotary encoder applications. It’s based on the same building blocks as what’s in digital calipers. We’ve been able to take that and adapt it into rotary sensing.

And we have our power line, which consists of a broad range of standard dc-dc converters, open- frame ac-dc power supplies, and external power adapters.

One of the main focuses for us with the Novum line—specifically our digital point of loads—is really driving interoperability within digital power systems.

Those three areas are currently our primary business areas, but where my team and I have been focusing is on our Novum® Advanced Power line. It targets the Intermediate Bus Architecture, and right now the products are primarily dc-to-dc converters from the Intermediate Bus converter all the way down to the point of load. CUI has been one of the first companies out there with a fully digital point-of-load module. We’ve also been working on some pretty exciting stuff with our Solus™ Power Topology, which is a new switching topology that allows us to get higher efficiency and greater power density for dc-dc conversion. It’s also very applicable on the ac-dc side.

What are some of the advantages of using the capacitive encoder technology over a standard optical encoder?

Optical definitely has the lion’s share of the market; it’s the known go-to technology. But some of the difficulties of optical are that you have to be very precise and very careful with the mounting of it. If you get a thumb print or something on the code wheel, you’re done. It’s very sensitive to dirty environments, which can lead to improper readings or functioning issues. Optical is also very susceptible to vibration because it usually includes a glass disk.

With capacitive encoders, because we’re not worried about optics, we can ignore the susceptibilities that exist with optical because they are not sensitive to those types of environments. We have one customer who has had a capacitive encoder mounted on a motor submerged in oil, and it’s still working. So they can work in a variety of environments that optical can’t.

And with regard to the performance, optical and capacitive encoders are the same. So it’s a nice alternative even if there aren’t environmental concerns.

What are the general applications for the Novum technologies you’re working on?

One of the main focuses for us with the Novum line—specifically our digital point of loads—is really driving interoperability within digital power systems. Digital offers the industry a great tool that provides a range of diagnostics and reporting information that hasn’t been readily accessible. The data that digital power offers would involve things like temperature feedback and current feedback so that someone can look remotely and see that, for example, a board is running hot or running a little bit more current. They can then schedule someone to perform maintenance.

Another goal is to be able to adjust the entire Bus to a particular voltage for the application to perform at its optimal efficiency.

The main issue with addressing these goals is the problem of interoperability. A power system is comprised of many different converters that must all be able to work together. In today’s systems, there is a high likelihood that these converters will be a mixed solution of POL modules and discrete board level designs. In the digital space, this presents a challenge because each controller and module manufacturer have slightly different protocols for the SMBus/I2C and proprietary serial buses. CUI is working to provide customers with digital power implementation options, whether a systems requires a mixed discrete/POL module or a full POL module solution.

Do you have development boards or other supplies for embedded solutions?

Yeah, we have development boards of our point-of-load modules and our Solus quarter brick, which we’ve recently announced. It is 445 watts per cubic inch, and an industry-leading 720 watts in the quarter brick package.

Can you tell us more about the Solus Power Topology?

It is a SEPIC-fed buck converter. So essentially what we did was we took a single-ended primary-inductor converter (SEPIC) and combined it with a buck converter for a new technology that provides the best advantages of both converters.

What the topology does by branching both the voltages and currents down multiple paths is it allows us to drastically reduce the switching losses in a buck converter. One of the best aspects that the Solus Topology offers is a 75 percent switching turn-on loss reduction. With that, we can get higher efficiency and higher power density because we’re not running as much voltage or current across any one component. It virtually eliminates the turn-off losses.

Because of some of the unique properties, we’re able to handle transients much faster than the typical Bus converter. Also, because we’ve significantly reduced the switching losses, it opens the door to some higher frequency converters. The options are almost endless with where we can go with the topology.

Do you have any tricks up your sleeve, such as a special way of analyzing problems?

I wouldn’t say I have any major tricks. I definitely like to break problems down into the basics or fundamental elements of the particular issue.

One key element that people should keep in mind with regard to power system design, in addition to thermals, is grounding. Pay special attention to how grounding is done on the board and in the design. I’ve found that this will save you a lot of headaches down the road.

Do you have any note-worthy engineering experiences?

I’ve caught multiple things in the lab on fire over the years! But other than that, nothing really note-worthy outside of the fact that I’ve had the pleasure of working side-by-side with a lot of really great engineers here at CUI and it’s been a lot of fun developing the company into a great, industry-leading technology company.

What is the culture like at CUI Inc?

While we are a highly-energized company focused on bringing innovative products and business practices to the marketplace, we are also a company that has a great family atmosphere and sense of community. We definitely think that what we have and what we’ve been able to do is a gift and a blessing, and now we’re trying to give back. We were recently able to take an afternoon and close down the department and go visit a Habitat for Humanity job site to donate our time. CUI does things like that at various times throughout the year, and is our way of giving back to the community. It’s one of the nicest aspects of working here. CUI truly is a company that cares a lot about giving back, and it’s great to be a part of it.