Pcbnew Footprint for EMI Filter

In my project i want to include a EMI Filter. But i cant find Footprint for the same in PcbNew.Please help.

It may help us if you include a link to the manufacturer’s Data Sheet.

My guess is that you will create a footprint for the filter module. It will probably have 5 (or 4, or 6) electrical pads at appropriate locations; a silkscreen outline of the module; and perhaps an unplated mechanical mounting hole or two. Fifteen minute’s worth of work for a user with moderate experience - about twice that for a new user.


1 Like

Thanks for reply.I got it, Component i want to use is Elcom Technologies.Yeah it of 5 pins,very easy to make.Only confusion now remain is,Schematic presently has is, 3 p​ins.Should i have to alter it too.Thanks

You said the schematic symbol has 3 electrical connections, but the physical package has 5 pins.

Are the two “extra” pins electrically connected to any of the three schematic terminals? KiCAD does not handle this situation very well. (Some discussion is in this thread: Multiple pins on the same net for a symbol ) I would place the extra pins on the schematic symbol, and add connections (on the schematic) between the pins that are internally connected.

Are the “extra” pins NOT electrically connected? (They may be on the package to strengthen the mechanical mounting, resist vibration, etc.) I would place them somewhere on the schematic symbol and mark them with KiCAD’s “No Connection” markers.


1 Like

Got it, I will modify existing EMI-Filter to EPCOS’s SIFI-B B84112-B-B110 , 5pin component. I will share it too, Thanks.

The manufacturer part number you listed is a system module in its own right. It is intended to be mounted on a chassis or enclosure, not on a PC board, However, I have seen an instance or two where they were mounted on a board.

Since it is a complete functional module, it would probably appear in a schematic as a rectangular block, with the proper number of pins (in this case, 5) and perhaps a text phrase identifying it as “EMI Filter”, or “Power Input Filter”, etc. The reference designator prefix will probably be either “A” or “U”. A schematic symbol showing the detailed internal circuit would probably NOT be used. After all, you don’t REALLY know how Epcos built it; at best, you can describe how it behaves in a circuit.

The footprint would consist of five pads, sized to accept the connecting wires, plus two NPTH mechanical mounting holes. The mounting holes must, of course, mate with the mounting holes on the EMI filter but you have freedom to place the electrical connecting pads at convenient locations.

(In a rigorous documentation environment, each of the connecting wires would have its own designator - W101, W102, etc. The spade terminals connecting to the filter would be designated W101P1, W102P1, etc. The pads on your PCB would probably be individually labeled as connectors - J1, J2, J3, etc - or perhaps consolidated into a (logical, not necessarily physical) terminal block such as “TB1”, with the individual connections identified as TB1-1, TB1-2, etc.)


1 Like

Thank you for your reply.I will do it as guided.