Tips for designing 4 pad feedthrough capacitor in Altium Designer

Question

I'm doing a PCB design in Altium Designer where I would like to include a feedthrough capacitor from Murata (MPN: NFM18CC101R1C3D). This is a special type of capacitor with 4 physical terminals where two of them are internally connected, i.e. 3 logical pins. I have not been able to find the component anywhere and the "IPC Compliant Footprint Wizard" does not include a such footprint.

My question is: What is the best way of making this type of component in AD

• Would you create 4 pads in the PCB editor where two of the pads have the same designator?
• Would you include the 3 recommended through-holes as part of the component or would you just include them as free via's in the board file?
• I would like to have the board produced at Seeedstudio which accepts a minimum via dimension of 12mil (0.305mm) hole and 25mil (0.635mm) diameter. Based on this I don't think the inner through hole will be possible to make. Can I simply skip this without having to worry too much about lost performance?

I'm looking forward to hear you suggestions.

Best Regards, Andreas

I'm new to Altium Designer

Answer 1

Large diameter thru-holes will have less inductance, which is your goal.

Murata's datasheet provides no spec in inductance, in fact not even acknowledging the ESL value.

I'd skip the middle hole, and place 4 large holes right outside the footprint, as shown

^{simulate this circuit – Schematic created using CircuitLab}