Navitas has developed the world's first 8.5kW power supply unit (PSU) for data center applications, which uses GaN and SiC transistors in a three-phase LLC topology to achieve 98% efficiency power for the next generation of AI and hyperscale chips.
The three-phase LLC topology is a common structure in high-efficiency power modules, which is based on a full-bridge inverter circuit and outputs a square wave voltage of a certain frequency. In LLC or LC resonant loops, a fundamental current is generated that lags behind the fundamental voltage. When the power device is turned on, the current flows through its anti-parallel diode, and the voltage clamp at both ends of the power device is zero, so as to realize the zero voltage switch-on, and then realize the soft switching of the DC-DC converter.
In three-phase LLC topologies, GaN and SiC transistors are power devices that can take full advantage of their high breakdown voltage, low on-resistance, and high thermal conductivity to improve the efficiency and reliability of power modules. At the same time, due to the fast switching speed of GaN and SiC transistors, the three-phase LLC topology can also achieve high-frequency operation, effectively reducing the size of inductors, transformers, and capacitors in the circuit, and increasing power density.
First, product features
High efficiency: By employing GaN and SiC transistors, the PSU achieves an efficiency of 98%, which significantly exceeds the efficiency level of conventional power supply units.
High Power Density: The PSU reduces the number of GaN and SiC devices by 25% compared to the closest competing systems, reducing overall cost and achieving a density of 84.6W/in³.
Compliant: The 54V output PSU is compliant with Open Compute Project (OCP) and Open Rack v3 (ORv3) specifications, ensuring compatibility and scalability with existing data centers.
Figure: Navitas unveils next-generation data center power supplies
Second, technical highlights
GaN and SiC Devices: The PSU uses 650V GaNSafe and 650V Gen-3 fast SiC MOSFETs configured in a three-phase interleaved PFC and LLC topology to ensure maximum efficiency and performance while reducing component count.
Three-phase topology: Both the PFC and LLC of the PSU use a three-phase topology (compared to the two-phase topology currently used for 8kW PSUs), which enables the industry's lowest ripple current and EMI.
Protections: Integrated control, drive, sensing, and critical protection functions provide short-circuit protection with a maximum delay of 350ns, 2kV ESD protection on all pins, elimination of negative gate drive, and programmable slope control.
Third, Market prospect and application
Meet AI data center demands: Up to 95% of the world's data centers can't meet the power needs of servers running NVIDIA's latest Blackwell GPUs, and Navitas' 8.5kW power design directly addresses these challenges for AI and hyperscale data centers.
Driving energy efficiency in data centers: As data centers continue to increase their energy efficiency requirements, power supply devices using wide bandgap semiconductor materials such as GaN and SiC will become the future trend. Navitas' PSU not only improves energy efficiency, but also reduces costs, supporting the green transformation of data centers.
In summary, the world's first 8.5kW AI data center power supply unit (PSU) announced by Navitas is powered by GaN and SiC, which has the characteristics of high efficiency, high power density, and compliance with specifications, which will meet the demand for high power and energy efficiency of AI data centers, and promote the improvement of energy efficiency and green transformation of data centers. It is reported that the PSU will be presented for the first time at electronica 2024 in Munich.
