How to quickly determine whether or not a SiC module (e.g. CAS325M12HM2) is damaged ?

C1Ron

We are using three CAS325M12HM2 SiC modules for our three-phase motor drive. Suspecting that one of the modules are damaged, we measure the resistance across each module, while still mounted to respective PCBs that hold banks of capacitors. When measuring the resistance across the the modules, the value fluctuates but we get values in tens of mega-ohms (~30 MOhms). However, when measuring one of the modules, the resistance settles rapidly to ~20 kOhms. Can we conclude that the module is damaged or should we carry out further testing ? Are there application notes for how to carry out such tests ?

Forum_Moderator

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TBhatia

Hi C1Ron,

It does sound like it could be damaged. The easiest way to check is with a multimeter. You can also check the resistance from gate to source of the suspect position without anything else connected to the gate/source. It should measure very high impedance if not damaged. Another check with the multimeter would be to look at the diode forward voltage to see if it's still reasonable.

This is the best thing to do short of fully characterizing the module on a curve tracer to see if it still falls within datasheet specifications.

Thanks

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.