MegaMini a Success

I have just finished the final version of the MegaMini. My take on the Arduino Mega in a very small form factor. It has all the same features of the Mega, plus a few more I/O pins broken out in under 1"x3". So if you are looking for a small Mega, here it is.

Note that I have changed the orientation of the USB connector in the production version.


That's really impressive! How many layers did it take?

Final retail price?

I was able to do it with only 2 layers. I routed all the traces manually without linking it to a schematic. I think that really helped since I could imagine the layout in my head, just had to get it in the computer. Most of the signal traces are 7mils wide with 7mil spacing.

I did the design in PCB Artist (free from so I don't have any eagle files. I like the functionality of PCB Artist it just sucks that it doesn't output an open format.

Final retail price will be about $60... currently offering pre-orders for $48. Will ship internationally.

Looks very cool. In your link to the product page you have a bullet item: ?Onboard USB programmer

What does that mean, how does it work, what can you do with it?

Also it states: "?Access to all ports of the Atmega1280" Are the 'missing pins" of the official Arduino mega board avalible only via direct port access statements, or have you made a modified core file(s) to be able to access them with digitalRead and digitalWrite statements?


I guess onboard usb programmer is incorrect. What it should say is Onboard USB->serial (FT232) for programming via the bootloader. Sorry for the confusion.

I haven't modified any libraries for access to the additional pins. So direct port access may be the only way to access them. I had to ship out all 22 of my prototype run to a client so I don't have any to test with. If need be I will supply modified libraries to access those ports with native Arduino code.

EDIT: I will probably wait for version 19 of the Arduino IDE before supplying modified libraries for the extra pins. That way I won't have to do it twice. It looks like 19 is supposed to be released in the next day or 2 according to the developers mailing list.

You might consider drawing up and providing a cross reference showing avr1280 port/pin names Vs Arduino pin names.

Already thought of that... will probably have some better docs done in a day or 2 which will include the Arduino pin mapping along with specifics of max voltage on the regulator and such.

19 is out in beta so you could use that to check it.


Awesome work. Will you add screw clearence holes for standoffs?

I wasn't planning on adding any screw holes. The design is meant to be as small as possible. Adding screw holes with enough clearance for everything would greatly increase the size of the board, defeating the main goal. This design was created for a client with specific needs and the form factor was the most important. In the future I may make a version that does have the mounting holes. If you needed to mount it with standoffs I don't see why you couldn't just clamp the 4 corners on a standoff.

The way I envisioned this being used was more like something at the end of a wiring harness and maybe a big piece of heatshrink insulating the board and securing all the wires in a bundle.

I appreciate all the input and will definitely take any suggestions in consideration.

Updated images of the production version here...

Hai Jeff


The holes place where's the ICs didn't located...very impresive.

I'm will thingking that also...for future design. ;)

Regards Jeckson