Because this is relatively new area, education is a key factor, and key seminars have been put online to help designers learn about the new topologies.
“We continue to invest in training, and TI sponsors the University of Florida,” said Lebouses. “It’s a great power school and I work with the faculty but getting students interested in hard core power electronics has been an industry wide challenge so getting 30 years of Unitrode knowledge disseminated on the Web, I think that’s just how people get knowledge these days.
“In addition to continuing with the series of power lectures, which we do every two years, this year we started a lighter version on HV interactive learning about the new topologies in terms of the problems they solve – here’s a real world challenge and a solution for that using the Web bench simulation which came from the National acquisition and now includes transformer simulation,” he said.
“We have also invested heavily in reference designs,” he said. “That [part of the business] acts like a customer and pushes us like customers, challenging us to think about from a customer perspective so some of the really relevant designs come from their customers. What we find is a lot of end equipment makers are trying to move away from third parties to do their own designs so they are having to learn about power supply design.”
“Energy efficiency is central to everything we do,” he said. “We have customers using GaN moving from liquid cooling to air cooling and that’s a huge saving, then there’s the DC-DC devices that have high efficiency so that we can remove the fan for ultrathin systems.”
A Ferrari transmission
Having a high efficiency converter design is not enough though.
“The analogy is you can have a Ferrari engine but if you don’t have a good transmission, ie the gate driver, then you are not going to get the best performance,” said Lebouses. “That’s why we put this business together to provide the whole power chain. Our strategy with the GaN switch is that it has to be integrated to get the full performance, avoiding the trace inductances that come from having it elsewhere on the PCB so we have the gate driver and GaN switch in the same package and that allows us to add over temperature protection and other protection.”
The power supply cannot scale with the power levels of the electronics, so the challenge is getting the higher switching frequencies, new topologies for planar magnetics and using wide bandgap devices.
“Many people, ourselves included, think that higher levels of efficiency provide a much larger usage of electronics with a 10 to 11% reduction in the energy they consume – 98 to 99 is a 50% improvement in what we have today,” he said. “There’s also a lot of devices that haven’t seen the efficiency levels that server and higher power systems have, such as cell phone and TV adaptors, so as a whole there is still room to grow and improve. But with industrial automation and vehicles there is a lot of room to improve.”
The other interesting part is that the vast majority of what used to go through power converters will move to inverters with renewable energy. “It will be over 80% going through inverters by 2030,” he said.
“To do this you need to get to a revolutionary change and there’s a lot to solve, from packaging to thermal performance. Both GaN and SiC are very sensitive – the gate of a GaN transistor is sensitive to overvoltage so you need very precise drive voltages and overvoltage protection,” he said.
For this to be industry wide, there also needs to be standards. “JC70 is the new JEDEC standard for wideband semiconductors, for specification and qualification, and we are pretty excited about that,” he said.