Continue to Site

Welcome to

Welcome to our site! is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

EMC Threshold range for different circuit

Not open for further replies.


Full Member level 1
May 28, 2020
Reaction score
Trophy points
Activity points

I have multiple modules in the product includes PSU and Mother board circuitry which are operating at different frequency.
Mother board is not yet designed yet and will be designed by other Designer.

I am designing PSU for the Same and Product should comply EN61000-6-3 which has Levels for Class B (AV)

0.15MHZ-0.5MHZ range 56dB to 46dB
0.5MHZ-5MHZ range 46dB
5MHZ-30MHZ range 50dB

now what margin i should consider so that both Mother board circuitry and PSU pass independently and When in Integrated.

Mother board circuit is designed by other person and i have to define dB levels for both.

EMC compliance must be achieved for the final product with typical application wiring (power supply, signal and communication cables). I don't understand what you mean by "have to define dB levels for both"?. Conducted emissions are measured at the external power supply lines, possibly also other external cables.

Question is which modules are expected to act as dominant interference sources and which are probably filtering and transmitting the interferences. In case of doubt, a switch mode PSU is able to generate noise over the full conducted 0.15 - 30 MHz range.

Hi FvM,

Thanks for the Answer.

Lets take example, my output is connecting to Mother board circuitry and in dependently it should pass the EN61000-6-3
So i need to give some data to other person that keep this dB value so we could pass both PSU and Microcontroller circuit separately and in Product.

Not open for further replies.

Part and Inventory Search

Welcome to