Dramatic frequency boost for SiC power MOSFETs
Cette publication existe aussi en Français
US startup NoMIS Power has significantly improved the short-circuit withstand time (SCWT) of SiC MOSFETs without increasing the on resistance.
This tackles one of the key challenges limiting the widespread adoption of SiC technology in high-power applications and allows for a higher frequency operation. This allows smaller magnetics for smaller, lighter power systems.
Rather than a SCWT of 2 to 3us, the latest 1.2kV, 80 mΩ MOSFET has a time of 5 µs. This improves the reliability of devices. Packaging improvements that impact junction-to-case thermal capacitance, alongside novel thermal management techniques with high heat transfer coefficients also increase the overall SCWT to up to 4x that of current devices.
This was achieved by tuning the trade-off between the specific on resistance (Ron,sp) and SCWT using a proprietary SiC MOSFET fabrication design and process flow and can be managed depending on the specific application. Complete optimization of SiC MOSFETs with long SCWT using this approach will allow NoMIS Power to further extend the SCWT while maintaining negligible impact on the Ron. The university spinout, based in Albany, New York, had shown significant device improvements at the IEDM conference last year.
The SiC devices are screened for latent defects and offer easier gate driver desaturation (dSat) design for high di/dt and dv/dt, enabling faster switching frequencies of up to hundreds of kHz. A longer short-circuit withstand time ensures rugged and reliable performance in critical applications, reinforcing the robustness of SiC-based power systems.
Applications sensitive to electromagnetic inference that cannot solely rely on digital control and sensing schemes to detect and act upon short-circuit events will now be able to effectively use SiC MOSFETs.
“At NoMIS Power, we have focused extensively on device architecture engineering, leading to a significant advancement in SiC short-circuit withstand time,” said Woongje Sung, CTO at NoMIS Power. “We believe this achievement provides valuable advantages to the power electronics community, helping engineers integrate SiC solutions with greater confidence in applications where robustness is critical.”
The devices will be shown at APEC 2025 this week in Atlanta, GA.
If you enjoyed this article, you will like the following ones: don't miss them by subscribing to :
