Design and Test, The Third

Filter Testing and Options

IN THEORY

In my previous posts, I'd debugged my power supply, and got my Arduino Leonardo clone up and running.

I'm getting closer to finishing but there's still one functional block that I'd not yet tested and it's my active filter.  Again, a big hat's off to Lior for the inspiration behind my build, but I have done some things my own way.

For example I used a Sallen-Key low pass active filter to get a 1.5kHz Low Pass Filter.

Thanks to the internet, rather than hand crank the numbers, I used this on-line calculator from OKAWA Electric Design. From that design I whipped up this LT-Spice File.

LT-Spice Circuit (Active Filter)

Design and Test, Part Two

Testing Day Two

As mentioned before, I'd tested and debugged my hardware to the point where it's time to start integrating the systems.  Or in other words get the micro talking to the rest of the board.

Notice Something Strange?