September 2020 - Why it’s tough to characterise SiC Power MOSFETs
Published on: 11/09/2020
Switching transients and parasitics can combine to thwart the accurate measurement of important MOSFET operating parameters
Silicon carbide (SiC) power MOSFETs get a lot of attention because they can switch fast while maintaining high blocking voltages. But their superior switching qualities also have potential drawbacks. Parasitic inductances caused by less-than-optimal board layouts, along with the SiC MOSFET’s fast dv/dt and di/dt qualities, can create voltage and current overshoot, switching losses, and system instability problems. To head off such difficulties, designers must understand SiC MOSFET switching qualities in depth.
Additionally, the extremely fast switching speeds of SiC MOSFETs also present challenges when characterising the devices. For example, equipment selection can affect test and measurement accuracy. The highly sensitive design and integration schemes of the driving and power stages also play a role in minimising voltage spikes, EMI, and switching losses.
Learn more about the challenges in characterising SiC power MOSFETs, including how to ensure test and measurement accuracy, principles of optimising the loop layout and the purpose of the gate driver design in Littelfuse's article written by Levi Gant, Xuning Zhang, Ph.D from Littelfuse and published by EE World Online, to view the full article click here.
An application note covers the Littelfuse Dynamic Characterisation Platform: https://info.littelfuse.com/littelfuse-dcp-download
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