Several years ago I had ordered five MSGEQ7 to eventually build a graphic equalizer. During my first attempts at it, I didn’t use any capacitors and couldn’t get it to work, so I gave up.
Fast forward to earlier this year when I decide I’m going to do something with these chips (project to be shown later) and tonight I finally break them out and give it a go.
The datasheet provides a working example of how to properly use the chip and I built up that example circuit; however, that didn’t work.
Next, I new Sparkfun had an Arduino Shield for the chip and they give both code examples and their schematics. So, I built that up, modified their code and….nothing. Garbage output.
I look for a third source and find this blog post. So I build it up and still garbage output.
At this point, I’m loosing my patience. Now I have cheap Chinese breadboads and sometimes they aren’t the best and since the circuit was so simple, I just pulled out a sheet of perfboard and made it. Still, nothing on the output.
Really upset now, I go to my drawer where I have extras and I pull them out and start popping them into the circuit and observing the output. The second one gives different garbage output, same with the third and fourth.
Finally, on my last one, I get some useful output. It isn’t perfect and one of the channels is garbage, but it is something.
So, with a somewhat working chip, I start to resort the defective chips to make sure I gave them a fair shake. As I put them back in and looked at the serial monitor, I still got garbage back. 🙁
I’m none too happy at the moment with this chip. I think I’d recommend people to get premade breakout boards. Yeah, they cost over $10, but it’s easier and faster to check for defects.
In the meantime, I have my own breakout board so if I ever feel like ordering more, then I’ve got something to test them with.