T-Board Microcontroller Breakout – v0.2 A Two-layer PCB

A Two-Layer Breakout

We were happy with our one-sided self-etched board as a proof of concept, and were now ready to move onto something that would approach a final product.  We made a number of changes to the design, which meant we needed to move to a two-layer PCB:

  • Power: We made the power more accessible.  Instead of presenting VCC and GND as separate female pins on the board, we chose to drive them straight into the breadboard
  • ICSP Header: it’s great to be able to program using an FTDI chip, but it’s harder to burn bootloaders and set the fuses on the chip, so we included an ICSP header
  • Silkscreen: Of course we can’t have a cool looking silkscreen on our self-etched board.
  • SMD Components: If you’re playing with microcontrollers on breadboards, you’re probably adept enough at soldering to handle a few larger SMD components – we therefore included a few 1206 resistors and capacitors, as well as a LED.  They’re fun…

Building a professional prototype PCB

After a load of research, and hearing of them on a few respected posdcasts, we uploaded our EagleCAD .brd files to OSHPark.  They are extremely competitive, turnaround times are good for our purposes, and it’s great to support a small company.  The render of our board is shown in this post.

OSHPark kept us in the loop, and the boards were shipped.  The wait was nearly over – we couldn’t wait to get a purple PCB in our hands!

Next: The boards arrive… and a lesson learned.