Problem EMC with LM5015

Hi

I use the LM5015 to convert the +24V in +6.5V.

The circuit don't pass the EN61000 because the power in the 250kHz-40MHz is too much.

I don't know how to solve this problem.

Have you a solution to reduce the power in the 250kHz-400MHz bandwith?

  • Hi Florian,

    give me more information about : "noise", power source, output power, switching frequency, efficiency on "full load, PCB (size and number of layers)...So fare  (i could not read values on schematic) i have some suggestions:

    -CMC is very effective in EMI reduction, on input and output power line (input filter  can bee smaller) 

    -Remove unused winding from transformer, and add Cu shield grounded on primary side

    -Add RC snubbers  across rectifiers (with scope you can verify reduction in "ringing" and "overshoots" )

    Dragan

  • In reply to dragan svalina:

    Hi Dragan

    Thanks for your answer.

    I already reduce noise by increase decoupling capcity to ground.

    I will test with an other transformer.

    Thanks