Reference design of CRD-30DD12N-K: SiC MOSFET C3M0040120K vs. C3M0075120K

gkim

Hello,

With respect to the reference design of CRD-30DD12N-K, I have a question on the SiC MOSFET on the main board.

The SiC MOSFET of C3M0040120K is employed for the rated power of 30kW for this reference design.

I wonder if the other SiC MOSFET instead of C3M0040120K might be able to be used when the rated power is less than 30kW for this reference design.

For instance, let us suppose that the rated power is 10kW.

Then may the SiC MOSFET of C3M0075120K be able to be used in place of C3M0040120K on the main board for this reference design?

Also, if C3M0075120K can be used on the main board, what would be the rated power for this reference design?

Thank you for your consideration.

With regards,

GKIM

TBhatia

Hello GKIM,

For evaluations like these you can use simulations platforms like PLECs that can help you with thermal and power loss analysis. Wolfspeed supports PLECS and LTspice simulation models for our discrete devices. For device selection, you can also use Speedfit Design Simulator (https://www.wolfspeed.com/tools-and-support/power/speedfit/) by choosing the topology, system specifications and use any of our device models to do your analysis.

Currently, we are in the process of incorporating the 3 Phase Interleaved LLC model into Speedfit. In the meantime, a member of our technical team is looking into your questions and we will respond shortly.

TBhatia

Hello GKIM,

Please find attached the summary of the maximum power rating, power loss and junction temperatures. using C3M0075120K instead of C3M0040120K. It is crucial to monitor the junction temperature if you are going to replace the device with C3M0075120K at all input and output conditions. The analysis was done for a typical Rds(on) of 75mO but the Rds(on) max at 25C for C3M0075120K is 90mO so please consider a power derating based on your temperature monitoring of C3M0075120K.

Thank you!

TBhatia

Hi, I hope that this answered your question. I will close this discussion for now but if you have a follow up question, please "Start a New Discussion" and we would be glad to support you further.