Technology: You’ve probably seen many USB chargers labeled as incorporating GaN or gallium nitride technology. But what is it, and do you need it?
Over the past year, you may have noticed that many companies that make USB chargers are talking about GaN, or gallium nitride, technology.
But what is this technology? What are the benefits of GaN? And do you need to upgrade all your chargers today?
To answer these questions, we need to take a little journey, one that gently touches on chemistry, physics and electronics.
What’s behind gallium nitride?
Gallium nitride (whose chemical formula is GaN) is a crystal-like semiconductor material with special properties. GaN has been used in electronics for decades, starting with LEDs in the 1990s, where it was used to emit light to illuminate televisions and computer monitors, before later finding its way into solar panels to convert light into electricity.
Today, GaN has found its way into transistors, replacing the industry’s former favorite semiconductor material, silicon.
What is a transistor, and why is GaN better?
A transistor is a tiny electronic switch that opens and closes very quickly. GaN has several advantages over silicon when used in transistors. Not only are GaN transistors smaller than silicon transistors, but they can carry more power, switch faster (about 40 million times per second, or about four times faster than silicon transistors), and are more energy efficient.
While silicon transistors have an energy efficiency of about 87%, GaN transistors increase this efficiency to over 95%.
What are the concrete advantages of GaN technology?
The reduction in transistor size means that new GaN USB chargers can be smaller than older chargers that work with silicon. And while it’s nice to have smaller chargers, it’s the increased efficiency that is the most important factor when it comes to USB chargers, because the more efficient an electronic component is, the less waste heat it generates.
In fact, the more efficient an electronic component is, the less waste heat it generates. And the less waste heat, the less chance of overheating and the less cooling the charger needs to operate safely.
Consumers are understandably concerned when chargers are hot to the touch. While it is common for chargers using silicon transistors to become almost too hot to touch, it is rare for a charger using GaN technology to be slightly warm
The faster switching also means that a GaN transistor inside a charger can have better control over the load and respond to events such as overheating or overvoltage much faster than older transistors.
This greater efficiency and faster switching is essential for modern USB-C chargers, as they support these increasingly large loads, with 100W loads now common and 240W chargers soon to be a reality.
Should you switch to this technology now?
Certainly, GaN chargers have many advantages. Does that mean you should throw out your old chargers and upgrade?
If you’re happy with your current chargers, keep them until you feel the need to upgrade, then choose a new GaN USB charger that meets your needs. If your chargers are trouble-free and do what you want, it would be a shame to scrap them.
However, if you need a smaller, cooler USB charger today, then choosing a GaN charger is recommended because you get all the benefits of modern technology for a minimal additional cost.