ATmega UNI - Universal ATmega PCB in Arduino UNO (shield) size

Notes (mostly pictures) about prototyping universal board with ATmega328P micro controller.

Experimenting around an idea that a base microcontroller board could allow for mote then host the microprocessor, but could have couple of more pins and pads for universal usage.

KiCAD schematics+PCB are on GitHub.

1st version

with small rgb led tht pads

2nd version

with normal tht pads

3/4th version

5th version


  • both microcontroller base board and prototyping shield
  • split inner and outer board pins, can be connected by jumpers or soldered using wire somewhere else
  • external or solder-on-board USB serial
  • allows for small size shields
  • parts with SilkS lines on both sides can be soldered on both sides to clear-up space when used as main-board or as a shield
  • Shield can be also attached from below the microprocessor - as the first layer
  • resistors, capacitors, fuse, leds - both smd or tht possible. using smd option leaves the tht pins for custom wiring

BOM for ATmega UNI *

Google Doc Spreadsheet