Integrated Power and Precision Cooling for 800 VDC Architecture

Author: Simon Ong, General Manager, Power Rack Business Division, Liteon Technology (Cloud Infrastructure Platform and Solutions) Collection: 2025 OCP Global Summit - Expo Hall Sessions

Summary

Liteon Technology presents its integrated solution for ultra-dense AI clusters powered by 800 VDC (0 to 800V, not +/-400V) architecture, addressing the jump from 120 kW racks at 48V to 1-1.2 MW racks requiring fundamentally different power distribution. The core argument is that 48V distribution at megawatt scale is physically impractical: bus bars would grow 8x in size with unmanageable copper losses and cooling requirements. By moving to 800 VDC, current transmission is reduced 16x, enabling dramatically thinner bus bars, lower transmission losses, and higher efficiency.

The Liteon total solution includes: a high-efficiency 800 VDC 1 MW power rack with 4-to-3 redundancy and front-panel maintenance, an ultra-durable IT rack supporting 3,500 kg payload (300% increase over previous generation), and a 2.1 MW thermal management direct liquid cooling solution with 3+1 independent hot-swappable pumps. The presentation identifies four key challenges for 800 VDC: safety protocols for high-voltage DC distribution, new semiconductor converter devices, complexity of thermal management at 1 MW per rack, and scaling/burn-in testing logistics for megawatt-class power racks. The 800 VDC architecture delivers higher efficiency, lower copper loss, lower carbon emissions, and better sustainability compared to 48V distribution. Q&A confirmed the system uses 0 to 800V (not bipolar +/-400V).