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LM5008A: Component blows up (from dv/dt?)

Part Number: LM5008A
Other Parts Discussed in Thread: LM5008


WIthout pre-charge before connecting, the component blows up above above a certain input voltage (the input pin burns up, and/or top cover burns up close to input pin). Output voltage instantly spikes to >20V. Normally in this circuit, output voltage has a rise time of 1-2 ms to final value 12 V, after an initial delay of ~1 ms.

This appears consistently at approximately 75 V, and only if a small enough fuse (high enough resistance) is used on the input (70 mohm - no issue, 30 mohm - LM5008 blows), which is the only damping in the input circuit (consisting of 3x22uF ceramic caps in parallel).

R_CL is currently at 470 kohm. Load is 22uF in series with 4.7 ohm resistor, nothing else. C_BST is 100 nF (recommended value 10 nF).

What would be the best way to mitigate this? Preferably without damping. It must be possible to hot swap 84 V supplies. Zener on secondary side?