Hi I have conducted CE102 Test and the results were not good.
I want to redesign my filter so I can attenuate 20dB at 430 Khz. the switching frequency is 440KHz
Can Anyone help me with the selection of common mode choke and capacitor so I can pass the test
currently I have used 1mH common mode choke and 4.7MFD capacitor.

 

hi Golz,
Check out this video.
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... Was reading the filter design article here:
filter design
What do you estimate the damping factor, ζ, to be?
Could it be a little low?

 

Change the common-mode inductor for one with greater inductance.
Or have two stages of filtering (better).
Also, be very careful with the layout. Keep the input and filter pairs of wires twisted (if wires) or close together (if PCB traces) and separate from each other.
C1, C2, C5, C6 must have low inductance connections to ground without any common impedance. Use a PCB ground plane.

 

Like Marley mentioned, the actual board layout is a very important part of the solution, and one that tends to be overlooked.