ATTiny85 Breadboard (TinyGrid85)

We love Arduinos and breadboarding but we often end up with projects which are really too small to waste an entire Arduino. We also wanted some way to breadboard our designs with an ATTiny85 part. Often times we just want one or two boards and find it hard to justify a new board spin.

A big frustration that we have with the Arduino is the lack of proper mounting holes. We think that boards should have mounting holes even if it costs a little extra for the PCB. And the mounting holes should take common hardware like #4-40 or M3 screws. Stuff we can buy at our local hardware store.

So we designed the TinyGrid85.



  • ATMEL ATTiny85 Microprocessor (or compatible 8-pin part)
  • Arduino Compatible (works with Arduino bootloader and Arduino IDE)
  • Prototyping area with power/ground connections
    • Brings out all 5 I/O lines and the reset line to grid columns
    • Laid out like a breadboard with vertically connected traces.
    • Power and Ground horizontal connections though all columns
    • Labeled (with letter numbers) for easy documentation
  • H1 - Jumper to select regulator or remove for ISP +5V
  • H2 - ISP Download Header (ATTiny85-Programming)
  • AP1117 5V Power Regulator with generous area under the regulator for heat dissipation
  • 2.1mm Connector for AC adapter 7-9V input
  • (4) 4-40 or M3 screw holes for solid mounting
  • 49x49 mm board

Technical Documents

Detailed technical documents are here.