A few years ago, I found myself in a friendly disagreement with Wurth Elektronik. I’ve always been a big fan of their whitepapers and products, and their EMC department has some incredibly knowledgeable people. Naturally, when I needed to design a mains EMC filter, I turned to WE for guidance.

About three years ago, I purchased their design kit and successfully built my first working mains filters. However, when it came time to refill the PCBs in my kit, I hit a snag. WE wouldn’t provide free refills, nor would they allow me to share the Gerber or Altium files to order new boards myself.

That was unfortunate, but it sparked an idea.

I decided to create my own Mains Filter PCBA. This design is freely available, including the Gerber files, so you can order the PCBAs or build your own EMC mains filter at no cost (aside from the PCB itself). The design is specifically tailored for WE components—which, by the way, you can sample for free!

You get an empty PCB! You need to samples your parts to your needs for free at Wurth Elektronik!