News: Microelectronics
26 June 2026
Infineon expands CoolSiC JFET portfolio with normally-off variants for AI data centers and industrial applications
In response to growing demand from AI data centers and the shift towards solid-state power protection, Infineon Technologies AG of Munich, Germany is expanding its CoolSiC JFET portfolio with new devices, package options and configurations, aiming to support high-performance power distribution and protection systems.
The first 750V and 1200V CoolSiC JFET devices in Q-DPAK packages, introduced last year, are now entering mass production. At the recent PCIM Europe 2026 (Power Electronics, Intelligent Motion, Renewable Energy and Energy Management) Expo & Conference in Nuremberg, Germany (9–11 June), Infineon presented additional package options and normally-off variants, further strengthening its discrete portfolio for applications such as solid-state circuit breakers (SSCBs), battery disconnect switches and power distribution architectures in AI data centers, including power supply units (PSUs), power backup units (PBUs) and intermediate bus converter (IBC) hot-swap and eFuse designs.
In these applications, power semiconductors operate predominantly in the on-state, while fault events are brief and infrequent. As a result, conduction losses, linear mode robustness, and avalanche capability are key design parameters. To address these requirements, Infineon is introducing a CoolSiC JFET 1200V in the widely used TO-247-4 package. With on-resistance (RDS(on)) starting at 5.0mΩ, it enables drop-in replacement in existing SiC MOSFET designs that use standard through-hole packages, without requiring PCB redesign. The portfolio is further extended by normally-off CoolSiC JFET configurations, combining a CoolSiC JFET with an Infineon OptiMOS low-voltage silicon MOSFET in a single package:
- The Dual Drive configuration provides separate access to both the SiC JFET and Si MOSFET gates, enabling full control and design flexibility at the PCB level. It also supports overdrive operation at VGS = 2V, reducing RDS(on) by around 10%. The 750V version is available in TOLL and Q-DPAK packages, while the 1200V version is available in Q-DPAK.
- The Cascode configuration integrates the SiC JFET gate internally and exposes only the MOSFET gate. This allows simple, plug-and-play operation with standard gate drivers and no need for specialized circuitry. It is suited for applications where both switching and conduction losses are relevant. The 750V version is available in a TOLL package.
The production-released CoolSiC JFET in Q-DPAK delivers RDS(on) values as low as 1.6mΩ (750V) and 2.3mΩ (1200V), which are reckoned to be among the lowest available in SiC at these voltage classes.
Picture: The 750V and 1200V CoolSiC JFET devices in Q-DPAK packages are now entering mass production, while Infineon is introducing a CoolSiC JFET 1200V in the TO-247-4 package.
All devices are based on Infineon’s .XT interconnection technology with diffusion soldering, improving thermal performance and robustness under pulsed and cyclic loads. They are qualified under real-world operating conditions to enable reliable performance during overload and fault events. Solid-state protection based on CoolSiC JFET enables switching speeds orders-of-magnitude faster than electro-mechanical systems, reducing damage risk, minimizing downtime, and extending system lifetime. In AI data centers, this fault isolation helps to protect high-value compute and memory assets while supporting higher power density and uptime. In industrial applications such as SSCBs, relays and battery management systems, the devices enable long-term conduction reliability combined with rapid fault isolation.
Picture: Infineon’s CoolSiC JFET portfolio is extended by normally-off configurations, combining a CoolSiC JFET with an Infineon OptiMOS low-voltage Si MOSFET in a single package.
With Q-DPAK, TO-247-4 and TOLL packages as well as normally-on, Dual Drive, and Cascode options, Infineon now offers a broad CoolSiC JFET discrete portfolio cover ing a wide range of RDS(on) ratings, gate drive concepts and assembly requirements with the valued reliability of its CoolSiC products.
The CoolSiC JFET 750V and 1200V in Q-DPAK will enter mass production in 2026. Engineering samples of additional variants, including TO-247-4, Dual Drive, and Cascode configurations, are now available and will also enter mass production in 2026.
