UCC28780: IC application for EMI noise issue

Danny

Thank you for reaching out. Our expert for UCC28780 will reply by the end of this week. In the meantime can you provide more information on your design? Are there any limitations, such as size, for any solution? The more details you can provide the better our feedback can be.

In the meantime, below are some more generic tips and training material we have on EMI filter design. Designing proper EMI filters, especially for high frequency and high density designs, is not a trivial step in the design process.

Component placement: parasitic coupling between components increases as they are placed closer together in high frequency designs. Try moving components farther apart to see how much of an impact their proximity has.

Proper transformer design: Common mode (CM) noise filtering can be greatly improved with proper design of the transformer. Details are in the following PSDS presentation.
Flyback transformer design considerations of efficiency and EMI
Paper: www.ti.com/.../slup338.pdf
Presentation Slides: www.ti.com/.../slup339.pdf
Presentation Video: training.ti.com/flyback-transformer-design-considerations-efficiency-and-emi

Best Regards,
Eric