IN Brief:
- Infineon and NVIDIA are expanding joint work on intermediate bus conversion within 800 VDC AI rack architectures.
- GaN converter designs support 800 V to 50 V, 12 V, or 6 V conversion with switching frequencies up to 1 MHz.
- Power-path protection and hot-swap functions remain separate requirements within the wider high-voltage rack programme.
Infineon Technologies is extending its collaboration with NVIDIA on gallium nitride power conversion for 800 VDC AI computing racks, concentrating on the intermediate bus converters that reduce distribution voltage before power reaches processors and other server components.
The latest work, presented alongside NVIDIA’s GTC Berlin conference, concerns the high-voltage conversion stage rather than a new rack deployment. Infineon identifies conversion from 800 V to 50 V, 12 V, or 6 V as configurations supported by its GaN portfolio, allowing power architects to consider different arrangements between rack distribution and the final processor supply rails.
Intermediate bus conversion addresses a growing electrical challenge in AI servers. As accelerator power demand increases, delivering large currents through conductors and circuit boards produces resistive losses and creates substantial demands on connectors, copper area, and cooling. Raising distribution voltage reduces current at a given power level, although the electrical system must then manage higher insulation requirements, fault protection, and efficient voltage reduction close to the load.
At 800 V, a high-voltage intermediate bus converter provides the link to lower voltage distribution inside the server. Additional point-of-load stages supply the tightly regulated voltages required by accelerator silicon and memory. The number and placement of conversion stages affect both overall efficiency and the physical space needed for power components.
Infineon is emphasising GaN switches because their switching characteristics can support operation at frequencies up to 1 MHz in suitable intermediate bus designs. Higher frequency can reduce the dimensions of transformers, inductors, and some other passive components, helping converters fit into restricted board height and area. Smaller passive components do not automatically guarantee greater system efficiency: magnetic losses, thermal management, gate drive behaviour, and circuit layout also influence the result.
Rapid semiconductor transitions introduce demanding design conditions. Parasitic inductance in current paths can produce voltage overshoot, while high rates of voltage change create electromagnetic interference and may affect adjacent circuits. Converter designers must therefore balance switching speed against electrical stress, filtering requirements, and the temperatures experienced by the power stage.
The GaN converter is only one element of the overall electrical system. Infineon is combining its power switches with PSoC Control C3 control devices and EiceDRIVER gate drivers, drawing on the control and drive circuitry needed to regulate switching and operate the converter under changing load conditions. The company also supplies silicon and silicon carbide technologies for other conversion and protection requirements, rather than describing GaN as suitable for every stage.
Choosing between 50 V, 12 V, and 6 V outputs has consequences beyond the nominal voltage ratio. Delivering equal power at a lower voltage requires proportionately more current, increasing losses and the size of conductors needed downstream. A higher intermediate voltage can reduce those currents but requires another conversion stage nearer the processor. The preferred arrangement depends on where electrical losses, heat, and available space can be accommodated.
These trade-offs become sharper as racks approach megawatt-class power levels. Converters must respond to changes in accelerator load without allowing voltage excursions to exceed the limits of downstream electronics. Infineon presents the combination of high switching frequency and reduced conduction and switching losses as a means of supporting higher power density, but has not supplied a new independently measured efficiency figure for the systems covered by this October collaboration.
The programme follows earlier work between Infineon and NVIDIA on serviceable 800 VDC server designs, first outlined in 2025. That work also covers power-path protection, including hot-swap controller functions used to manage startup, connection, and fault conditions. Such protection is distinct from the intermediate bus converter: an efficient converter does not by itself make a high-voltage rack safe to service.
Infineon chief executive Jochen Hanebeck described GaN-based system solutions as an important part of the companies’ approach to AI power infrastructure. The current expansion draws together semiconductor devices, control technology, and converter architecture, while the associated protection functions remain essential to serviceability.
Neither company has disclosed a new production commitment, conversion efficiency benchmark, or installation timetable specific to this work. The October work concentrates on GaN intermediate bus conversion within the existing 800 VDC programme; efficiency, fault response, and serviceability will still have to be demonstrated together in complete rack implementations.
