Tool/software:
Hi Team,
As we are proceeding with the UCC28704 Flyback converter, we identified that the Zenner Diode placed in the return current part of primary transformer. Which is only available in SLU603B - Design tool calculator schematics, and it EVM board schematics or the TI- Webbench schematics. could you please let me know what exactly function of the Diode and should we need to mount in out project or not ?
Thanks,
Sakthivel
Hello,
That diode is part of the TVS clamp that is needed to protect the FET from and over voltage, it clamps/dissipated the leakage energy. So, it is needed.
Please note that I would recommend you use and RCD clamp instead of a TVS clamp. In the bottom schematic this is formed by CA, RA, DA and RC. Diode Dz is added for safety. The following link will bring you to an application note and there is a section on how to setup the RCD clamp. https://www.ti.com/lit/an/sluaac5/sluaac5.pdf
Regards,
