LNK623: compatible with TSD-1017 transformer?

Posted by: sighinolfi on 09/08/2011

Hi,

i have just update a circuit by introducing the link-switch LNK623 instead of an old TOP209. In my circuit a TSD-1017 transformer is used. Now, with LNK623 mounted, the transformer emits a buzz, a whistle, that i couldn't hear before. Perhaps the LNK623 is not completely compatible with that transformer? Is there some precautions i should have to perform my circuit? I would like to mantain the TSD-1017 transformer if possible.

Thanks in advance,

Andrea.

Comments

I am not sue about the exact operating conditions. What is the amount of load which was there on the output when you here the buzz. If possible can you capture the drain to source voltage waveform with both the parts.

Could you please share the schematic and board layout as well.

Regards,

PI-NANO

Hi,
thank you for your reply; here is the schematic related with the component and the transformer, and a caption of the drain to source waveform..
Thanks in advance,
Andrea

Hi,

Thank you for sharing Drain to source voltage waveform and schematic. The drain to source voltage waveform seems to be something unusual. I could not understand why the relaxation ring was increasing again. I wonder if there was some noise getting coupled into the feedback pin. Can you share the following things?

1. Electrical Specifications of your design

2. Complete schematics

3. PCB Layout

So that I can have better understanding what’s going on.

Regards,
NANO