Gallium Nitride (GaN) – the Technology Behind Smaller, Better Chargers

So there seems to be a clear, simple answer to my question regarding why Anker and Aukey’s sub-$20 20W power USB-C power adapters are so much smaller than Apple’s — they use gallium nitride (GaN), and Apple’s apparently does not. Tim Brookes, writing at How-To Geek back in January:

GaN chargers are physically smaller than current chargers. This is because gallium nitride chargers don’t require as many components as silicon chargers. The material is able to conduct far higher voltages over time than silicon.

GaN chargers are not only more efficient at transferring current, but this also means less energy is lost to heat. So, more energy goes to whatever you’re trying to charge. When components are more efficient at passing energy to your devices, you generally require less of them.

So these GaN chargers are much smaller, the same price as Apple’s or cheaper, and more energy efficient. There seemingly is no downside or catch. Until I hear otherwise I’d say there’s no reason anyone should buy Apple’s 20W adapter instead of Anker’s or Aukey’s. (Those are Amazon affiliate links to make me some money.) I’ve ordered both, and will report which I prefer. Aukey’s even comes in black, which gives them the early edge.

The next question, obviously, is why isn’t Apple using GaN for its 20W charger? Perhaps it’s an issue of scale — maybe because GaN is a relatively new technology, Apple can’t make enough of them?

Update: Turns out Anker’s Nano seemingly is not using GaN. When they revised it to go from 18W to 20W, MacRumors ran a story with this note appended:

This article originally stated that the new Anker Nano was a gallium nitride (GaN) adapter, but Anker has since clarified that this is not the case.

And while Anker does call out GaN on the product pages for some of its chargers, it does not for the 20W Nano. In their FAQ, regarding how the Nano can be both faster and smaller, Anker more or less just attributes it to secret sauce:

Anker’s exclusive highly-integrated technology uses a stacked design with custom magnetic components to reduce size, boost efficiency, and improve heat dissipation. This allows Anker Nano to support an 20W max output, while being just as small as a 5W iPhone charger.

And when you search for “Gan” on Aukey’s site, a bunch of their chargers are listed, but not the Omnia 20W Mini. So I don’t think Aukey’s 20W charger is using GaN either. That just makes me all the more curious what their secret sauce is, and why theirs are so much smaller than Apple’s.

Thursday, 29 October 2020