onsemi has expanded its power semiconductor portfolio with the launch of the GaNEXUS family, a series of gallium nitride (GaN) transistors ranging from 40 V to 650 V. Designed for AI data centers and industrial automation, the line aims to increase power density by up to two times while reducing magnetic component size by 60%.
Engineering the Shift from Silicon to Gallium Nitride
The semiconductor industry is currently navigating a fundamental transition in power electronics, moving away from traditional silicon MOSFETs toward wide-bandgap materials like gallium nitride (GaN) and silicon carbide (SiC). As of July 2026, the thermal and switching speed limitations of silicon have become a primary bottleneck for high-density AI server racks and energy infrastructure.
onsemi’s GaNEXUS platform targets these specific inefficiencies. By utilizing GaN’s superior electron mobility, the transistors achieve significantly faster switching speeds than legacy silicon alternatives. This reduction in switching loss is critical for the 48V power architectures increasingly common in AI data centers, where energy conversion efficiency directly impacts operational costs and cooling requirements.
According to onsemi, the GaNEXUS Smart 650 V models integrate protection features directly into the transistor package. This design choice aims to simplify the system-level design process, reducing the need for external supervisory circuits that often complicate board layouts and introduce points of failure.
Performance Metrics and System Integration
The technical advantages of GaNEXUS are most pronounced in applications requiring high power density. In high-voltage environments—such as DC-DC converters and power factor correction (PFC) stages—the company reports a 0.5% to 1% efficiency gain and a 60% reduction in the physical footprint of magnetic components like inductors and transformers.
Integration with the company’s existing Treo platform provides a unified approach to power management. Treo acts as the control and sensing layer, meaning developers can theoretically move from prototyping to production more rapidly by relying on a validated ecosystem rather than stitching together disparate third-party components.
- GaNEXUS FET Range: 40 V to 650 V
- Power Density Improvement: 1.5x to 2x increase
- Magnetic Component Reduction: Up to 60% smaller footprint
- Efficiency Gains: Up to 2% improvement in low/medium voltage applications
- Packaging: Optimized for cooling (TOLL, TOLT, and dual-side cooling)
Market Context: The Power War in AI Data Centers
The introduction of GaNEXUS comes as AI hardware demand continues to strain existing power infrastructure. As compute clusters for Large Language Models (LLMs) scale, the power delivery network (PDN) has become as vital as the GPU architecture itself. Industry analysts at IEEE Spectrum have noted that the move to 48V bus architectures is a necessity to manage the massive current loads required by modern AI accelerators, a trend that directly favors the adoption of GaN-based power stages.
This move places onsemi in direct competition with other power-semiconductor leaders like Infineon and EPC (Efficient Power Conversion). While Infineon has historically leveraged its broad portfolio of CoolGaN products, onsemi is attempting to differentiate by offering a “total system” approach through the Treo platform. This strategy mirrors a broader industry trend toward platform lock-in, where vendors provide the full stack—from the controller IC to the power FET—to ensure compatibility and thermal reliability.
The 30-Second Verdict for Infrastructure Architects
For engineers tasked with designing high-density power supplies for AI hardware, the GaNEXUS rollout represents a shift toward more integrated, pre-protected components. The primary benefit is not just the raw efficiency gain, but the reduction in board space and cooling complexity. By shrinking magnetic components by over half, designers can increase the power-to-volume ratio, allowing for denser server configurations without hitting thermal throttling limits.
However, the transition to GaN remains a design challenge due to the high-frequency gate drive requirements. Developers should consult the onsemi design documentation to evaluate the gate drive constraints when integrating these FETs into existing architectures. As the industry moves toward more aggressive power density targets, the ability to maintain stability at these higher switching speeds will determine the long-term viability of the GaNEXUS ecosystem.
For further technical specifications and development kits, engineers can access the documentation via the official onsemi GitHub repositories or their developer portal. The success of this rollout will likely depend on how effectively the company supports the transition for teams currently optimized for legacy silicon MOSFETs.
