As AI datacenters scale up massive GPU clusters, power distribution is moving from legacy 48 V architectures to 800 V DC rack systems. Microchip Technology and Navitas Semiconductor have introduced an 800 V DC-to-6 V DC reference design to help engineers adopt this new power architecture faster.
Architecture and key components
The reference platform combines Microchip’s dsPIC33AK Digital Signal Controllers (DSCs) and TA100 CryptoAuthentication security IC with Navitas GaNFast NV6034 GaN FETs.
- dsPIC33AK256MPS306 provides deterministic digital power control for high‑frequency, high‑efficiency DC/DC stages. It features a 200 MHz 32‑bit core with double‑precision FPU, 78 ps high‑resolution PWMs, and multiple 12‑bit ADCs running up to 40 MSPS.
- TA100 establishes a hardware root of trust, enabling secure boot, authentication, and protected firmware updates — essential for connected, OCP‑compliant power systems.
Together, they form the control and security foundation for Open Compute Project (OCP) 800V DC rack power supplies.
Power delivery board and GaN advantages
The power delivery board (PDB) uses 16 × NV6034, 650 V, 17 mΩ GaNFast FETs in a stacked half‑bridge topology on the primary side. The DFN 8×8 dual‑side‑cooled package reduces thermal resistance, allowing higher continuous power while maintaining very high efficiency.
Target performance figures:
- 1 MHz switching frequency
- Up to 96% peak efficiency at full load
- Around 2,100 W/in³ power density
By combining GaNFast power devices with digital control and hardware‑based security, this reference design gives power engineers a practical blueprint for next‑generation AI datacenter rack supplies, aligned with the OCP 800 V DC standard and ready for advanced, secure power delivery applications.
Source: Electronics Weekly
