NVIDIA, Navitas collaborate on 800 V HVDC architecture

NVIDIA’s next generation of 800V DC architecture aims to establish high-efficiency, scalable power delivery for next-generation AI workloads, to ensure greater reliability, efficiency, and reduced infrastructure complexity.

Today’s existing data center architecture uses traditional 54 V in-rack power distribution and is limited to a few hundred kilowatts (kW). Bulky copper busbars are required to transfer this low-voltage electricity from the rack-mounted power shelves to the compute trays.

As power increases above 200 kW, this architecture runs into physical limits due to power density, copper requirements, and reduced system efficiency.

Modern AI data centres require gigawatts (GW) of power for the increasing demand for AI computation. Nvidia’s approach is to directly convert the 13.8 kV AC grid power to 800 V HVDC at the data centre perimeter using solid state transformers (SST) and industrial-grade rectifiers, eliminating several AC/DC and DC/DC conversion steps, maximizing efficiency and reliability.

Due to the higher voltage level of 800 V HVDC, the thickness of copper wires can be reduced by up to 45%, due to I²R losses, where the same amount of power can be delivered with increased voltage and lower current. Using a traditional 54V DC system, over 200 kg of copper would be needed to power a 1MW rack, which is not sustainable for next-generation AI data centres with GW power demand.

The 800V HVDC directly powers the IT racks (eliminating the need for additional AC-DC converters) and is converted by DC-DC converters to lower voltages, which will drive GPUs, such as the Rubin Ultra.

Navitas is an established leader in AI data centre solutions enabled by GaN and SiC technology. The high-power GaNSafe power ICs integrate control, drive, sensing, and critical protection features, enabling unprecedented reliability and robustness.

Navitas says that GaNSafe is the world’s safest GaN with short-circuit protection (350ns max latency), 2kV ESD protection on all pins, elimination of negative gate drive, and programmable slew rate control. All these features are controlled with 4-pins, allowing the package to be treated like a discrete GaN FET, requiring no V_CC pin.

Additionally, Navitas offers a family of medium voltage (80-120V) GaN devices, which have been optimized for secondary side DC-DC conversion, delivering high-speed, high efficiency, and small footprint, for AI data centers PSUs with outputs of 48V-54V.

Offering the industry’s broadest voltage range – stretching from 650 V to ultra-high voltages of 2.3 kV to 6.5 kV, the SiC technology has been implemented in multiple projects for MW energy storage and grid-tied inverters with the Department of Energy (DoE).