Which is the best LLC gate drive transformer?

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cupoftea

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Hi,
The three depicted Gate drive transformers here are for driving hi side LLC FETs when Vin is at 400VDC.
It appears to be clear that these three are the best three single output Gate drive transformer configurations possible.
Which of the three is best? A or B or C?

(LTspice sim and jpeg schem attached)
 

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Hi,
We actually think B is best.......because its fastest and doesnt have leakage inductance overshoot...but the current through R12 when the FET turns off puts a voltage across R12, which in turn, prevents the PNP from turning on fast enough.......so i believe it needs something doing with diodes to prevent this current flow through R12, or divert it somewhere else. Can you think of a way?
 

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