LinkSwitch-TN2 not working properly in Buck configuration

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We have designed a 5V buck based on DER-507(https://ac-dc.power.com/sites/default/files/PDFFiles/der507.pdf) using LNK3206D.
But the output is 64V as opposed to 5V.
Circuit diagram attached. The HV+ and HV- is from a 120uF capacitor on a 100W TOP259 Flyback supply. We used ES1J(600V, 1A, 35ns) for both the diodes.
We have already tried swapping out LNK3206D(with that from a different vendor) and replacing 1.2mH general purpose axial inductor with 2mH Ferrite core inductor. All cases behaving in the same manner.
LED D51 not populated.

AttachmentSize
LNK3206_Buck.PDF18.81 KB

Never mind, it worked.

Hi PratyushJayachandran,

Apology for the late reply. Please let us know just in case you have further inquiries.

Thanks and Regards,

PI-Lupin the Third

Is SC1099 equivalent to LNK3206?
My local PI representative told us that SC1099 can be used instead of this but on reading the datasheet I found that SC1099 doesn't have any reference for operation on buck mode.
Is there some other inexpensive Semi Custom part or other series that I can use for Universal to 5V, 300mA, transformer less buck convertor?

Hi PratyushJayachandran

Good Day!

For input 85Vac - 265Vac and 5Vo with 300mA load Buck topology application, LNK3206 is suited for this application. I suggest that you use the standard Power Integration part.

You can register and use the Online PIExpert to compute for the design circuit values.
https://piexpertonline.power.com/site/login

Application note for LNK TN2 is AN70.

Thanks

Regards

PI-Chloe