Sanan Optoelectronics Uses Low-Resistance SiC Substrates and S²I-ARCP Soft Switching to Redefine the Energy-Efficiency Boundaries of AIDC Power Supplies

AI computing power infrastructure is being built at a rapid pace, and server power supplies have become key to determining data center power usage effectiveness (PUE) and operating costs. Current mainstream power supplies must meet 80 PLUS Titanium (≥96%), and traditional silicon-based devices are approaching their physical limits.

Material breakthrough: low-resistance SiC substrates overcome an industry challenge

Hunan Sanan, a subsidiary of Sanan Optoelectronics, has spent three years tackling the problem and achieved a breakthrough in low-resistance SiC substrates: the average resistivity of silicon carbide substrates has been stabilized at 11 mΩ•cm, half that of the traditional mass-produced 20 mΩ•cm, while indicators such as stacking faults, dislocations, micropipes, and surface morphology are benchmarked against mass-production standards, successfully solving the industry challenge that "low resistance and high quality" cannot be achieved at the same time. For every 1 mΩ•cm reduction in SiC substrate resistance, device on-resistance can drop by 0.2%–0.6%. For server power supplies, this means lower heat generation, smaller heatsinks, and higher switching frequencies, thereby shrinking transformers and capacitors and helping power modules move toward ultra-high efficiency and small size.

System innovation: the S²I-ARCP topology unlocks the value of SiC soft switching

SiC has faster switching characteristics, but high dv/dt amplifies system constraints such as EMI and insulation. To fully realize the value of SiC in AIDC, system-level coordination among devices, topology, and drivers is required. To this end, Sanan Optoelectronics proposes S²I-ARCP (single shared inductor auxiliary resonant commutation pole)—using one shared auxiliary inductor to serve three phases, reducing magnetic components. An 800V/15kW prototype built with Sanan SiC MOSFETs achieves wide-load efficiency exceeding 99.6% and supports natural convection cooling; under the same operating conditions of 30kHz/10kW, device temperature can be greatly reduced by about 50°C, and dv/dt is controllable and set to 6.7kV/µs. It also covers soft-switching optimization of Planar SiC MOSFETs in parameters such as Rg,int, Ciss, and Coss, clarifying the selection trade-off thinking for the Coss×Rdson FOM in high-frequency LLC/CLLC resonant DC/DC for server power supplies, automotive OBCs, and telecom power supplies.

Device matrix: precisely matching mainstream soft-switching topologies for server power supplies

Sanan Optoelectronics has built a complete SiC MOSFET product matrix. Its AIDC solutions cover 2300V/35mΩ, 1200V 14/20/26/32/40mΩ, and 750V 9/14/18/27/35/50mΩ, and offer a variety of package forms such as TOLL, TOLT, X2PAK, and QDPAK, precisely targeting PSU LLC/CLLC resonant DC/DC and SST/HVDC soft-switching scenarios, with both low on-resistance and superior Coss×Rdson (FOM) combined advantages.

At present, in the AIDC field, Sanan's products have been delivered in volume to leading server power supply and data center infrastructure companies at home and abroad, and long-term agreements have been signed with multiple customers. Through the supply chain systems of leading server power supply and infrastructure core partners, the company's products have been successfully applied in the AIDC scenarios of end customers such as NVIDIA, Google, Microsoft, and Amazon, fully covering the world's mainstream AI computing power and cloud infrastructure platforms.

From "faster SiC" to "SiC that better understands systems," underpinned by wide-bandgap innovation, massive computing power becomes more energy-efficient and more efficient.