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TechGirl
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5 questions asked First question asked
Hey guys, I'm trying to parallel SiC MOSFETS, is that possible? And what about dynamic imbalances?
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Harmon
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First question asked Welcome! 5 replies posted
Yes, SiC MOSFETs has a positive temperature coefficient on relevant parameters like RDSon and Etot enabling static current sharing during parallel operation.
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Abhilash_P
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50 likes received 500 replies posted 250 solutions authored

Hi,

     Despite their fast switching speeds, SiC MOSFETs have some advantages compared for hard paralleling. SiC MOSFETs typically have a higher Rdson positive temperature coefficient PTC. This PTC acts as negative feedback during static current sharing. If one chip is taking more current that chip gets hotter, increasing the Rdson value and hence reducing the current as negative feedback, so reducing the possibility of thermal runaway. 

    SiC MOSFETs show a very small increase in switching losses with temperature greatly reducing this factor. In addition, SiC MOSFETs have a softer transconductance curve meaning that small changes in gate voltage in the gate threshold region have a smaller effect on drain current. This aids in dynamic current sharing.

 

Regards,
Abhilash P

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