Ultrasmall Arduino with 328P-MU QFN32

Hi there,

I'm in the process of evaluating the feasibility of creating an Arduino compatible board based on the 328P-MU which is the same uC of the UNO or Duemilanove but it came in a 5x5 mm QFN 32 package, suitable for ultra small applications.

Anyone ever worked on this? Advices? Tought?



Smaller than an Arduino Nano?

Yeah, using small package SMT capacitors, the ATMEGA 328 in QFN32 package and 0.05" spaced pins and possibly using a 4 layer PCB is actually possible to reduce the size considerably.

The goal would be to design a board at least 1/2 the size of the Nano.

The goal would be to design a board at least 1/2 the size of the Nano.

The Duemilanove is at least half the size of the Nano. :wink:

Perhaps you meant “at most”.

Yep, sorry… I’m Italian and sometime I get confused with language…

X = size of the Pro Mini
Y = size of an arduino compatible board based on QFN32

It should be possible to reach:
Y <= X/2

Connectors have been the usual problem. If you're willing to do 1.27mm connectors on four sides, you can get a lot smaller. But it will also be a lot harder to use. How about offset 2.54mm connectors on top and bottom? Either set could still plug into a breadboard.

Hi westfw, thanks for your suggestion.

I actually thought about that as a possibility.. It could work, I should do some designs as tests to check for it's feasibility..

Anyway, I don't think that breadboard compatibility is actually important as I imagine this board to be used in very specific applications. Eg, It could be a good thing to have for people already having PCB designing experience and they could just as a building block in size constrained applications when they would need to add Arduino intelligence to their designs..

I think that's a cool idea. I've been thinking about a shield for high altitude balloon/rocket tracking, and having a much smaller Arduino available would be cool for some variants.

I think this SIP version is pretty cool. I am going to try this and the ardweeny when I finish my supply or promini's.

Development started.

See: http://www.varesano.net/blog/fabio/femtoduino-designing-ultrasmall-arduino-compatible-board-atmega-328p-qfnmlf32 http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1293672993/0