My own ATMEGA328-PU micro-controller.

Hey guys,

Been working on something for a few days now.
It's a micro-controller what looks a bit similar to the Arduino UNO.
I used the EAGLE 6.5 for the designs of both the schematic and the board itself.
I am also updating a topic on EEVblog for this, getting a bit of feedback there.
I hope you guys can help me make it better as well.
First I used a ferrite-bead, this is now a proper inductor.

//NOTICE: I will update this first post whenever there is a change and leave a comment to notify the people, it'll keep this post much cleaner. I will make some sort of change log.

{24-03-2015 Post 2}
Changed quite a bit.
Here is a summary and three images.

A few quick changes:
* I changed the power LED parallel 1K resistors to a single 500 Ohm in a fitting 0603 package.
* All LED's are a 0603 package now.
* R3 & R4 are closer to U1 and are now a 0603 packages.
* R7 & R8 are now also 0603 packages, they are also re-routed.
* C8 & C10 & C11 are now fat-caps (Panasonic D types) instead of nice and tiny smd's, suggested due to stability/standardization(?).
* C2 & C3 are now 22 pF instead of 20, due to recommendations from an external source.
* Added the 100 nF cap as suggested.
* Did some re-routing all over the board.
* Added more ground via's.
* Changed the tDocum to tName to actually have the info on the solder mask.
* IC4 has a bigger copper slab to hug with now, it helps with keeping IC4 a bit cooler.

Also, I am thinking about inserting a 28-pin ZIF socket on the board instead of a dip socket.
Would be more user friendly in the case of the wish to change chips.








{24-03-2015 Post 1}
//EDIT: Seems that I can't add pictures as attachments, here are two url images instead.

Ah, got some issues during a wiring check, pin 18 & 19 are shorted by pin 17's trace and some little trace angle errors, plus IC4 needed a little more copper slab to hug with, going to change more, maybe take the auto-reset out, unless I find a way to make it more reliable.
Ideas are always welcome.
Also, here is the link to the EEVBlog topic: http://www.eevblog.com/forum/projects/my-first-try-at-a-micro-controller-based-on-the-arduino-uno-firmware/

I am working on it, one of my datacom teachers actually has an ATMEGA328P-PU running as a private internet of things server, it's struggling but doing it's thing.
I will soon look into the schematics for Ethernet and try to implement his driver for the 328-PU, the only downside is that the 328(P)-PU only has 32Kbytes of flash, that's a bugger, but if you run in on a low-profile without too much force it could run as a geiger counter that has on-board Ethernet..
Here a little reference:
But I am still working on this beastie, I first aim on getting the basics on a strong level..

Oh and I really need a cheap supplier for a small quantity of PCB's.
I will get the components via GE, I think, I prefer quality components throughout testing and manufacturing.
Eventually GE will get the full production run, but for now their PCB's are too expansive. (Darn optimizer lab guys, nibbling from the funds whilst re-routing a trace or two at max)

Oh and Dan, I think you will receive a complete one, I could use a third tester.
I am planning on making it Arduino UNO IDE compatible(It i right now) so that debugging and programming the flash is a piece of cake.
Plus you know a bunch about electronics, so yeah, quite valuable during this process.
As I do lack expertise on this stuff, I only had a very basic schooling on electronics, most is self-thought.

Hence I also ask for help.

Got a bit of an update now.
Re-made the full board, a bit more clearly now.
Also swapped 4 resistors into a single res-array.
Shuffled some most of the components on the board and the NCP1117ST50T3G now has a double sided pad for heat dissipation, coupled by 8 via's with a 0.508 mm hole. (0.2 inch?)

Will have to do some work still on the soldermask documentation, but it's OK for now.
The board is now 106.68 x 78.74 mm in size and fits well within the euro-boards, might even fit twice.
After this one I might continue on a smarter one, maybe a hub, switch or a router?
Don't know, will see.

Or would there be something that anyone on here would enjoy?
It's a good point to learn from for me, plus I still need to learn a ton about designing a board, even though my current board is rather small, it could be smaller.
I enjoy using the 1206's a bit too much.
Smaller components could be an idea, though.
As long as the polarized caps stay their sizes.
Learned that the hard way today. >.> One blew up on me, an smd type, whilst having it on the 5v rail from the power plug, a test of the power circuit at school, so not a full board.

Let me know what you think.
It's open source hardware, so feel free to edit it and sending a revised version back.

//EDIT: These Eagle files contain the fixed messyness at T1, whoops.
Eagle 6.5.0 files:


Images: