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    Would ganging IGBTs resolve power and thermal handling demands

    The IGW75N65H5XKSA1 can dissipate 395W & has 0.38 K/W thermal resistance to case (to-247) circuit demands ~500W handling (this is the measured average and with a ~30W margin) surpassing the IGBTs capability and maximum operating temperature. Nominally, for 1 transistor the temp would sky rocket to 215C from 25C baseline, question is if I were to gang 2 or more IGBTs would the resultant temperature for each IGBT in the gang simply be the quotient of 215C and number of parts in gang? Whats a good rule of thumb temperature to keep IGBTs from going into thermal runaway condition?
    Last edited by Zak28; 16th May 2018 at 08:53.

    •   Alt16th May 2018, 08:48

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    Re: Would ganging IGBTs resolve power and thermal handling demands

    Yes you can parallel igbt's - ideally their Von goes up with temp for best paralleling, remember 395W is at Tcase =25C, at 100C case the power handling is de-rated quite a bit (read data sheet carefully) having really good thermal bonding of device to device really helps keep all the dies at the same temp and hence helps keep the currents the same in each device ... you want really good gate drive and very symmetric layout so that one device does not take up all the turn-off or turn-on losses ...


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    •   Alt16th May 2018, 12:17

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  3. #3
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    Re: Would ganging IGBTs resolve power and thermal handling demands

    question is if I were to gang 2 or more IGBTs would the resultant temperature for each IGBT in the gang simply be the quotient of 215C and number of parts in gang?
    Yes, if you fulfill post #2 guidelines. But the real question is, can you keep the case at 25C ? The ambient is likely to be at 25C, not the case.
    Whats a good rule of thumb temperature to keep IGBTs from going into thermal runaway condition?
    That depends on how much margin you want to leave. You are the one to decide.
    You want to have a margin below Tj(max)=175C ... that depends on you and the reliability you want to give to your circuit, economy etc.


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    •   Alt16th May 2018, 12:46

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  4. #4
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    Re: Would ganging IGBTs resolve power and thermal handling demands

    for long life equipment Tj of the igbt < 120 deg C depending on the power being dissipated, this could mean a case temp of < 100C or far lower
    Last edited by Easy peasy; 17th May 2018 at 00:06.


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