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Snubber for LT3958 inverter

I implemented the inverter per data sheets guidance and it worked pretty well, but during emissions tests we found an emission peak centered around 420MHz and after further investigation, we found it was caused by ringing on the anode of the schottky diode of the inverter.

After a search for guidelines in AD site and the Internet I found a document "RC Snubber Design in EZBUCK Circuit". Based on the document, I estimated the CT of the diode (B240A-13-F) ito be 110pF and the leakage inductance to be 1.3nF. So the value of the RC snubber was Cs=330pF and Rs=6.9 Ohms. I used 10 Ohms as it was the value at hand. After the change, I got

And the emission around 420MHz basically vanished.

Below, a simplified version of the circuit with the snubber (different diode though).

Is this approach OK? Is there something that I may be missing with this solution? Maybe a better approach?


Thanks in advance.