Bare Die LTspice model_Tj can not be left floating

StephenLML

Currently, I am working with the LTspice model of Bare Die, such as CPM2-1200-0040B. According to the Wolfspeed SiC MOSFET LTspice Model Quick Start Guide，the Junction Temperature terminal(Tj) can be left floating. However，it can not work with the floating Tj. How can I solve this problem? Because I don't want to keep it constant through an external voltage source.

Thanks!I really appreciate any help you can provide.

Forum_Moderator

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TBhatia

Hello StephenLML,

You can either add a RC network to represent the thermal management system you have in your design for the die to ambient OR you can simply add the ambient temperature as the voltage source and the model will use the inherent junction to ambient thermal impedance Rth,ja.

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.