Video line-up: Gallium nitride semiconductors at APEC 2017

The recently concluded APEC 2017 in Tampa played host to a lot of technological developments involving GaN semiconductors. Here are a few of the demos on the exhibit floor that highlighted what these wide band gap devices can do for power circuits.

In the future, your TV set may not need a power cord if the wireless power technique from the folks at EPC catches on. As explained in this short video with Alex Lidow, a typical TV consumes about 125 W which can easily be handled with the AirFuel wireless charging standard. The secret is to use GaN switching transistors to handle the 6.78 MHz switching involved, a frequency that is too high for silicon devices. GaN switchers are also good at compensating for load changes that would characterize wireless appliance power.

When Texas Instruments put together a reference design for a power supply using GaN power devices, the result was a circuit that took up about a third of the space normally occupied by a silicon-based design. In this video, TI’s Masoud Beheshti describes a three-stage supply that includes an isolated LLC topology.

The old way of creating power modules with gallium-nitride power devices was to just substitute GaN devices for silicon equivalents in the module chassis. The resulting modules just didn’t perform up to their potential. As explained by GaN Systems’ Jim Witham in this short video, new module designs pay better attention to heat transfer and internal inductance to boost module performance.

Chargers for appliances such as cell phones get a lot smaller when they make use of GaN power transistors. In this short demo, Bob Card and Souhib Harb of ON Semiconductor show an example of what’s possible through use of a GaN power controller IC that employs a new active-clamp topology.

Charge pads can now juice up multiple wireless devices simultaneously thanks to gallium-nitre FETs. This short demo by GaN Systems’ Jim Witham reveals a 70-W charging pad built to the AirFuel standard that has a two-inch throw, a feat possible only through the use of GaN semiconductors able to switch at AirFuel’s 6.78 MHz frequency standard.

Gallium-nitride transistors are still considered exotic technology in some circles, but they are up to their fifth commercial generation. EPC’s Alex Lidow goes through a quick demo to show, among other things, the 3x improvement in power density these devices bring compared to comparable silicon MOSFETs.