I continue working on my micro boost effect. After the first take and doing some more research on noise, I decided to go with the 2nd version of the board. I did very small changes to the original circuit, keep on reading for the new schematic and other photos. You can skip straight to the video, this time it’s a short one – I promise.
Improved Schematic
Here’s Version 2 of my schematic:

I used OPA379 (OPA379AIDBVT) op-amp, I also have TLV313 (TLV313IDBVT) but I didn’t use it this time. Both are in tiny SOT23-5 package. The pin-out is interchangeable but make sure to choose SOT23-5 package. For more notes see the previous two posts.
The changes are not huge. Some inspired by my previous post, some, I just did not need such big value capacitors. Also, I changed coin cell battery holder. The biggest change is I went with lower gain of the circuit.
In the video I sing praise to KiCad, but truly it’s a wonderful piece of software. One thing I messed up (KiCad can’t read mind still!), I copy pasted wrong 100n cap, so I ended up with the wrong footprint (I had to use caps that are not the ones I prefer). Well, something to fix for Ver 3 😁.
Some Screenshots
I did a pretty nice board in KiCad:

If you watch the video, the finished board looks pretty much like what you can see in 3D view in KiCad:


I ordered the boards directly from KiCad – friends from PCB Way sent me 5 boards – great quality as always. Thanks fellas!!! And the final result looks pretty much as the screen shots above.
Video
Have a look at the video – I managed to keep it short – yay!!
Btw, if you want me to share the project files, let me know (with ideas how the best to share them ;))
2 replies on “Micro Thunder Boost – Ver2”
If instead of keeping the board soldered to the guitar cables you want to be able to disconnect the effect (and quickly connect the cables) you can use a mix of JST XH and JQ connectors. For the cables, use XH2.54 3 pin male and female, and for the board, 03JQ-ST on one side and S3B-XH-A on the other. Afaik, XH and JQ are inter-connectable, so you can put the board in between the XH connectors. Sadly the JQ don’t come in 2 pin varieties, but a 3 pin is small enough, I think. Just an idea. Cheers!
Thanks for the tip. I used them a long while back. Using them for board-to-board connection sounds interesting. If I remember correctly, assembled cables are available to purchase too. I’ll look into that, last time I tried assembling my cables I hated it 😀