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    thermal impedeance junctoin to case

    This transistor does not have max junction temperature listed but has derate value 267mW/C and power dissipation 20W. Is there any way to obtain its thermal resistance junction from case from listed parameters?


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    Re: thermal impedeance junctoin to case

    Yes, the derating number is equal to thermal impedance. It's by the way referring to Tj,max of 100°C.


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    Re: thermal impedeance junctoin to case

    Quote Originally Posted by FvM View Post
    Yes, the derating number is equal to thermal impedance. It's by the way referring to Tj,max of 100°C.
    Thereby 20watts / 0.267derate = 74.906367 this is over 25c ambient which makes permissible junction temperature at 99.906367C. This is what you were referring to as 100c max?



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    Re: thermal impedeance junctoin to case

    That's how it works.


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    Re: thermal impedeance junctoin to case

    This particular part doesn't appear to be computable as no derate or junction temperatures are listed however its quite a large transit frequency for such a part, these are typically slow. Can max junction temperature be obtained from only listed parameters?




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