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  1. #1
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    LTspice Wolfspeed mosfet model doesn't seem to be working

    Hi,

    I've set up a simple circuit in LTspice using a model of Wolfspeed's C3M0075120K. I'm feeding the gate a square wave but I'm only seeing tiny current spikes at rise and fall going through the mosfet.

    This probably isn't the ideal way to drive a mosfet, but it's just a simple test I set up after discovering the problem while trying to drive a half-bridge using a model of the UCC21520 isolated gate driver (it worked fine until I swapped the existing mosfets for these ones).

    Am I doing something wrong or should I contact Wolfspeed?

    Datasheet: C3M0075120K

    Circuit: files.zip

    Click image for larger version. 

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  2. #2
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    Re: LTspice Wolfspeed mosfet model doesn't seem to be working

    Connect disconnected pins too (Tj Tc). Don't let them floating. I see 2.4A if they are grounded.
    "Try SCE to AUX." /John Aaron/


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  3. #3
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    Re: LTspice Wolfspeed mosfet model doesn't seem to be working

    Hi,

    try to connect V1 Minus directely to GND instead of KS.

    Klaus
    Please don´t contact me via PM, because there is no time to respond to them. No friend requests. Thank you.



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  4. #4
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    Re: LTspice Wolfspeed mosfet model doesn't seem to be working

    Thanks for your replies.

    Connecting Tj and Tc to ground fixed my issue. I thought I could leave them floating because when searching the internet for a fix, I came across this manual. On page 7, it says Tj can be left floating, and it says Tc can be left floating, but I failed to read the highlighted note which says one of them should be connected to a voltage source.



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