Other Parts Discussed in Thread: , TPS82130, PMP23278
Hi all,
We have designed a device using the TPS23754 PoE controller. We have followed the TPS23754EVM-383 design as reference. The 12V generated by the fordward converter is then steped down to 4.2V and 5V by two TPS82130 buck regulators. The 4.2V may supply up to 4A and the 5V up to 1A.
The device has been tested in an anechoic chamber to test EMC and we have had some issues:
As it can be see in the images above, there are 3 frequencies out of range or really close to be out (125MHz, 500MHz and 750MHz).
After this test we added a ferrite clamp to the cable (74271221 from Wurth Electronik) and the results were as follow:
The 500MHz peak is still there.
Would somone have a suggestion on how to reduce EMI?
The schematic of the design is attached.
Thank you very much in advance.
