German researchers just blew the doors off what we thought was possible with GaN power chips. Fraunhofer IAF has cooked up a monolithic bidirectional switch that handles 1200 volts—and it comes with integrated free-wheeling diodes baked right in. That’s a big deal for anyone betting on the next generation of electric vehicles and grid-tied power systems.
The 1200V Leap
Most EVs today run on 400V architectures, with 800V systems slowly gaining traction. But the industry is already eyeing 1200V as the sweet spot for serious long-distance driving and electric trucking. Higher voltage means lower resistance, which translates to faster charging and less energy wasted as heat. Fraunhofer’s new switch, built on their proprietary GaN-on-insulator technology, uses highly insulating substrates like silicon carbide or sapphire to boost breakdown voltage while keeping the chip compact.
The monolithic design blocks and conducts current in both directions, saving precious die space and cutting conduction losses. That’s because there’s only one split depletion region to worry about—a neat trick that simplifies the whole power stage.
Simplifying the Stack
On the low-voltage side, Fraunhofer also showed off a clever hack: using a single-gate GaN HEMT as a bidirectional switch in a 3-level T-type converter. Normally, you’d need two gates for bidirectional control, but this approach cuts complexity while keeping everything space-efficient. It’s a reminder that sometimes the smartest innovations aren’t about raw specs—they’re about making the system easier to control.
What’s Next
Fraunhofer isn’t stopping at 1200V. They’re already working on components for the 1700V class, and their PCIM booth is stacked with 8-inch GaN wafers, half-bridge modules, and integrated power ICs. The message is clear: GaN isn’t just a niche material anymore—it’s the backbone of tomorrow’s power electronics. And with bidirectional switches like this, the road to faster, more efficient EVs just got a whole lot shorter.
