GaN FETs for high-density power conversion in AI data centres, industrial and charging systems

Renesas Electronics Corporation has introduced three new high-voltage 650V GaN FETs for AI data centres and server power supply systems, including the new 800V HVDC architecture, e-mobility charging, UPS battery backup devices, battery energy storage and solar inverters. Designed for multi-kilowatt-class applications, these fourth generation plus (Gen IV Plus) devices combine high-efficiency GaN technology with a silicon-compatible gate drive input, greatly reducing switching power loss while retaining the operating simplicity of silicon FETs. Offered in TOLT, TO-247, and TOLL package options, the devices provide engineers with the flexibility to customise their thermal management and board design for specific power architectures.

The new TP65H030G4PRS, TP65H030G4PWS and TP65H030G4PQS devices utilise the robust SuperGaN platform, a field-proven depletion mode (d-mode) normally-off architecture pioneered by Transphorm, which Renesas acquired in June 2024. Based on low-loss d-mode technology, the devices deliver superior efficiency over silicon, SiC, and other GaN offerings. Moreover, they minimise power loss by reducing gate charge, output capacitance, crossover loss, and dynamic resistance impact, while maintaining a higher 4V threshold voltage, which is not attainable with today's enhancement mode (e-mode) GaN devices.

Built on a die that is 14% smaller than the previous Gen IV platform, the new Gen IV Plus products achieve a lower RDS(on) of 30mΩ, reducing on-resistance by 14% and delivering a 20% improvement in on-resistance output-capacitance-product FoM. The smaller die size reduces system costs and lowers output capacitance, resulting in higher efficiency and power density. These advantages make the devices ideal for cost-conscious, thermally demanding applications where high performance, efficiency and small footprint are critical. They are fully compatible with existing designs, allowing for easy upgrades while preserving existing engineering investments.

Available in compact TOLT, TO-247 and TOLL packages, they deliver one of the broadest packaging options to accommodate thermal performance and layout optimisation for power systems ranging from 1kW to 10kW, and even higher with paralleling. The new surface-mount packages feature bottom-side (TOLL) and top-side (TOLT) thermal conduction paths for cooler case temperatures, enabling easier device paralleling when higher conduction currents are required. Furthermore, the commonly used TO-247 package offers customers higher thermal capability, allowing them to achieve higher power levels.

"The rollout of Gen IV Plus GaN devices marks the first major new product milestone since Renesas' acquisition of Transphorm last year," said Primit Parikh, vice president of the GaN Business Division at Renesas. "Future versions will combine the field-proven SuperGaN technology with our drivers and controllers to deliver complete power solutions. Whether used as standalone FETs or integrated into complete system solution designs with Renesas controllers or drivers, these devices will provide a clear path to designing products with higher power density, reduced footprint and better efficiency at a lower total system cost."

Like previous d-mode GaN products, the company's new devices utilise an integrated low-voltage silicon MOSFET—a unique configuration that achieves seamless normally-off operation while fully capturing the low-loss, high-efficiency switching benefits of high-voltage GaN. As they utilise silicon FETs for the input stage, the SuperGaN FETs are easily driven with standard off-the-shelf gate drivers, rather than the specialised drivers typically needed for e-mode GaN. This compatibility simplifies design and lowers the barrier to GaN adaptation for system developers.

GaN-based switching devices are quickly growing as key technologies for next-generation power semiconductors, fuelled by demand from EVs, inverters, AI data centre servers, renewable energy, and industrial power conversion. Compared to SiC and silicon-based semiconductor switching devices, they provide superior efficiency, higher switching frequency and smaller footprints.