Infineon Technologies launches 400 V MOSFET series targeting AC/DC power conversion for AI servers

     Due to the growing power demands of Artificial Intelligence (AI) processors, server power supply (PSUs) need to provide increasing amounts of power while still fitting within the specified dimensions of server racks. The increase in energy demand for high-level GPUs is the main driving force behind this trend. It is projected that by the end of the decade, each chip could consume 2 kW or more. Infineon Technologies AG has decided to expand the development of SiC MOSFETs to voltages below 650 V due to the increasing demands of applications and unique client requirements. The business is currently introducing the new CoolSiC™ 400 V MOSFET family, which is built on the second generation (G2) CoolSiC technology that was previously released earlier this year.

     Infineon has created a new MOSFET portfolio specifically for use in the AC/DC stage of AI servers. This portfolio complements Infineon’s recently announced PSU roadmap. The devices are well-suited for solar and energy storage systems (ESS), inverter motor control, industrial and auxiliary power supplies (SMPS), and solid-state circuit breakers for residential structures.

     The new family exhibits significantly reduced conduction and switching losses in comparison to the current 650 V SiC and Si MOSFETs. The AC/DC stage of the AI Server PSU, which is implemented in a multi-level PFC, can achieve a power density of 100 W/in³ and has been demonstrated to achieve an efficiency of 99.5 percent. This solution demonstrates a 0.3 percentage point increase in efficiency compared to solutions utilizing 650 V SiC MOSFETs. Furthermore, the integration of CoolGaN™ transistors in the DC/DC stage finalizes the system solution for AI Server PSUs. By utilizing a blend of high-performance MOSFETs and transistors, the power supply is capable of providing over 8 kW of power, resulting in a power density increase of more than 3 times when compared to existing systems.

     The updated MOSFET collection consists of a total of 10 items. These include five different RDS(on) classes ranging from 11 to 45 mΩ. The MOSFETs are available in Kelvin-source TOLL and D²PAK-7 packages, with .XT package connectivity technology. The drain-source breakdown voltage of 400 V at T vj = 25°C makes these components well-suited for applications in 2- and 3-level converters, as well as for synchronous rectification.

     The components exhibit exceptional durability in challenging switching situations and undergo thorough avalanche testing to ensure their reliability. The advanced and durable CoolSiC technology, along with the .XT connection technology, allows the devices to handle unexpected increases in power and fluctuations produced by abrupt changes in the power needs of the AI processor. Both the connectivity technique and a low and positive RDS(on) temperature coefficient allow for exceptional performance in situations where junction temperatures are elevated.