LMR54406: parasitic capacitance and inductance value

Hi team,

My customer is using LMR54406 (Buck Converter).

And they tested a -1.8V negative voltage at SW pin when the high side MOS closed. And it  last about about 60ns from -1.8V to 0.

The test method is as recommended.

So I think it because the output inductor drives the current through the circuit of low-side MOSFET during switching operation. And the parasitic inductance and capacitance related with MOSFET will cause oscillation while loading current increases.

I want to calculate this voltage and last time for analysis.

So would you please provide the Coss or Cds of the internal MOSFET and the parasitic inductance for me?

(If the real number is confidential, would you please tell me a typical number?)

Thanks and Best Regards,

Brian Li