Check out this amazing little chip: It’s a full microprocessor with 4 ins and outs and I’d really like to use it in a future design, but that opens up a can of worms. You see, the moment I put digital stuff in a pedal I need to to EMC testing to get a CE mark to sell in Europe, and that is exactly as confusing, expensive and wildly ambiguous as you might expect.
Now, a CE mark is a self-certified promise you’ve stuck to the rules and done all the safety tests, and on an analogue, low voltage pedal that’s all very easy and trivial. The difficulty kicks in with digital, where you need that EMC test.
However, as far as I can tell so far, there is no actual need to spend £1000’s on tests if you can show you did them yourself. And for the purposes of these chips we are only clocking in the low Megahertz and so I am confident I can build a shielded chamber, antenna and spectrum analyser and plot a reliable emissions graph covering clock frequencies and their harmonics with high accuracy and confidence.
What’s really interesting is that this is something I have wanted to do for a while anyway. Our parent company (SM Robotics Ltd.) has an interest in rugged testing of electronics for use in hardened environments such as space and nuclear and so I’ve been developing some serious test gear for that for some time. EMC testing falls perfectly within that remit.