UCC28950: Question about Overcurrent protection on short-circuit test condition

When tested the short-circuit condition for UCC28950, output FET were broken.

I think that overcurrent protection could not response because inlush current is too fast on short-circuit test condition.

Please let me know about two points below for measure the overcurrent protection and short-circuit test condition;

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①Is there countermeasure for FET broken by external component?　

　I think that small Css become fast response for overcurrent protection, is this good idea?

　If there the other idea, please let me know.

②Is there any document for short-circuit test on UCC28950(or UCC28951)?

　⇒For example, application note, reference design, design guideline, etc.

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Customer condition is below;

・Input： 750V

・Output： 140V/10A

・fsw： 100kHz

・Configured overcurrent protection threshold： 16.5A

・Inlush current on short-circuit test： About 50A

・Four output FET are also broken

・FET： IPW90R340C3（Infineon）

　www.farnell.com/.../83257.pdf

・FET Driver： UCC27528

・Switching voltage is clean (no problem for high overshoot and overvoltage)

Best regards,

Satoshi