Reference design CRD-22AD12N: SiC MOSFET C3M0032120K vs. C3M0040120K

gkim

Hello,

With respect to the reference design of CRD-22AD12N, I have a question on the SiC MOSFET for the main board.

The SiC MOSFET of C3M0032120K is employed for this reference design.

May I replace the device of C3M0032120K with the C3M0040120K for this refrence design without any influence on its performance?

The only difference between them is the Rds(on). It is 32mohm for C3M0032120K whereas 40mohm for C3M0040120K.

Thank you for your consideration.

With regards,

GKIM

TBhatia

Hello, thank you for your message. A member of our technical team is looking into your questions and we will respond shortly. 

TBhatia

Hello GKIM,

Replacing C3M0032120K with C3M0040120K will impact the performance of converter.

The Rds(on) is higher for C3M0040120K therefore the conduction losses will be higher. The switching losses are lower for C3M0040120K compared to C3M0032120K.

You can run a quick simulation https://www.wolfspeed.com/tools-and-support/power/speedfit/ comparing these 2 devices in the AFE topology with the system specifications to know the actual impact on the conduction losses, switching losses and junction temperature.

You should make sure, the junction temperature of the device does not exceed 135degC when you replace C3M0032120K to C3M0040120K.