Onsemi Showcases 20kW AI Data Center Power Prototype Using Vertical GaN
Onsemi displayed a prototype intermediate bus converter using its proprietary 1200V vertical GaN technology to directly step down 800V DC to 6V for AI data centers.
At the electronica 2026 trade show in Munich, Germany, semiconductor company Onsemi showcased a prototype 20kW-class intermediate bus converter (IBC). The device uses Onsemi's proprietary 1200V-rated vertical gallium nitride (GaN) power devices to directly convert an 800V DC input to a 6V output, targeting the shift toward high-voltage DC power distribution in AI data centers.
As computing power increases in AI servers, traditional 48V or 52V distribution schemes require higher currents that increase transmission losses and cable size. Moving to 800V DC distribution reduces these losses but requires stepping down the voltage near the processors. By converting directly from 800V to 6V, the system eliminates intermediate conversion stages like 48V or 12V buses.
Onsemi's approach relies on its vertical GaN architecture, where current flows through the thickness of the chip rather than across its surface. This structure allows for higher voltage ratings and current density compared to conventional lateral GaN devices. The company claims this design can reduce chip size by approximately one-third compared to commercial lateral GaN products. The prototype utilizes an LLC resonant conversion topology with MHz-band switching frequencies to shrink magnetic components like transformers. According to the display panel at the event, the prototype achieved a conversion efficiency of 96.5%.
Onsemi representatives noted that the 1200V rating avoids the need to series-connect two 650V lateral GaN devices, simplifying the circuit. They also highlighted that GaN's lack of reverse recovery charge benefits electromagnetic interference (EMI) performance. However, they cautioned that GaN devices are sensitive to gate-source voltage control and require careful layout and thermal management due to their small chip size. This demonstration positions Onsemi against competitors such as Renesas Electronics, Texas Instruments, Navitas Semiconductor, STMicroelectronics, and Infineon Technologies, who have also announced developments in 800V-to-6V power systems for AI infrastructure.