I have a question about a safety related issue in an offline flyback converter, I plan to use the TOP267KG.
I am evaluating cases with a singular component failure that may expose a user to dangerous voltage levels at the output of a flyback converter with 24 V output voltage and wide range mains input. In case the secondary diode fails and shorts, the mains voltage divided by -Np/Ns of the transformer is applied on the output pins of the converter during the conduction phase of the primary FET (in my case: -70 V). I want to make this safe by putting a second diode antiparallel to the output capacitor (D58 in attached picture). This diode would get forward biased in above mentioned failure case and limit the output voltage of the circuit to safe levels.
Is this a valid approach, or does the TOP267KG already protect the output from such failures? Similar ICs from e.g. ON (FSQ0565) specifically have protections for these cases (in ON's case: Abnormal Over-Current Protection), but I couldn't read from the TOP267KG's datasheet if it features something similar.
Thanks and regards