Infineon Technologies has released a 24kW SiC-based battery backup unit (BBU) DC-DC reference design for high-voltage DC power architectures in AI data centers.

Infineon Technologies Korea announced on the 15th that it has unveiled a 24kW BBU reference design for AI data centers based on a high-voltage DC bus. This design was developed to support direct operation between the battery stack and the 800V DC bus by applying 650V and 1200V silicon carbide (SiC) technology.

This reference design is based on a multi-level, multi-phase non-isolated structure. It features a combination of stacked, interleaved, and coupled boost and buck stages to reduce the volume of magnetic components and simplifies system configuration by integrating charging and discharging paths. Infineon explained that this structure enables zero-voltage switching (ZVS) across the entire operating range, contributing to reduced current ripple and fast transient response.

The module size is 112×88×118mm, and it integrates a 24kW main power stage and a 2.4kW auxiliary power. The charger and discharge blocks are designed to share EMI filters, capacitors, and protection MOSFETs to reduce the number of components. 650V CoolSiC MOSFETs are used in the power conversion stage, aiming for an efficiency of over 99% and a power density of 450W/in³.

As the proliferation of AI servers rapidly increases power requirements per data center rack, power distribution structures are also changing. The industry is considering high-voltage architectures based on 800V DC or ±400V DC to reduce the current burden and wiring losses associated with existing low-voltage distribution methods. In this structure, the BBU is considered a key device that maintains server power in response to power outages, generator switching, and grid anomalies.

Infineon stated that this design enables support for high-voltage DC buses in a form factor similar to existing low-voltage BBUs, contributing to improved space efficiency and thermal management in data center power infrastructure. The related SiC JFET products, IGK048B041S and IGK120B041S, are currently available.