SMPS > 150KHz = bad for EMC?

[eem2am]

Hello,

Is it true that it is always best , if possible, to keep the switching frequency of an SMPS below 150KHz because that is the lowest tested frequency declared by the EMC regulatory bodies?

 

[FvM]

If you only expect interferences from your SMPS fundamental, yes. In practice, you have to use considerably lower switching
frequencies to count on this feature, e.g 25 to 30 kHz, and avoid any fast switching components. It seems to me, that some low cost
designs are trying this way.