POWER CIRCUIT BOARDS Fraunhofer IAF embeds GaN power ICs as half-bridge in PCBs
Researchers at the Fraunhofer Institute for Applied Solid State Physics IAF (Fraunhaufer IAF) have integrated their GaN power ICs using PCB embedding technology to create an extremely compact and efficient voltage converter.
Energy-efficient power electronics for conversion and transmission applications are becoming extremely important. This is because technologies of the future, including sustainable energy concepts, depend on them. Now, researchers at Fraunhofer IAF in Germany have developed what they call a user-friendly, highly integrated gallium nitride (GaN) voltage converter in a compact package that is both resource-efficient and can be used modularly.
Enabling a compact system design
For several years now, power semiconductors have been used in voltage converters to meet the demands on energy supply and usage. It is not only the semiconductor materials themselves that play an important role, but the packaging and design of the components too. This is because the smaller and more compact the package is, the more efficiently they work.
However, a compact design is often difficult to reconcile with the discrete standard components that currently dominate the GaN power electronics industry. As such, the critical conductor loops between transistors and power supply have to be designed individually and wired as circuits from discreet components.
This is where the so-called user-friendly alternative developed at Fraunhofer IAF comes in.
Here, a research team has embedded their innovative GaN-based power ICs as a half bridge in a printed circuit board (PCB) which features all the critical wiring within the package. The result, it is claimed, is an extremely compact and efficient voltage converter that is suited for all 600 V applications and enables a reliable and modular system design.
DC-DC efficiencies of over 98.8 percent at 350 V
The high integration density of Fraunhofer’s GaN Power ICs enables a higher performance density, higher reliability, and higher compactness in contrast to other circuits due to the integrated sensor technology. With their GaN Power ICs in a half-bridge circuit, the researchers have managed to achieve DC-DC efficiencies of over 98.8% at 350 V.
“GaN-on-Si technology allows monolithically integrated circuits for half bridge converters but does not solve the wiring problem to external capacitors. However, these critical connections to gate drivers and DC link capacitors are essential for clean and efficient switching behavior. With our goal of a perfect voltage converter in mind, we were looking to find the optimal highly integrated packaging technology for our GaN Power ICs”, says Stefan Mönch, a researcher at Fraunhofer IAF.
Fraunhofer IAF presented its latest GaN power electronics at PCIM Europe digital days on July 7-8 2020.