RSGC ACES PCB Tips

Recommendations for ACES Learning EAGLE

  1. For all but the simplest breakout boards, invest the time to assemble a working prototype first (don't guess, no matter how confident you might be)
  2. All complex software applications are quirky, EAGLE is no exception. Accept it.
  3. Finding the EXACT part you require can be a real challenge. To this end I actively maintain two EAGLE Parts libraries (Through Hole and Surface Mount) containing the parts most often used by ACES (ACES_THT.lbr, ACES_SMT.lbr). You'll also find these links at the top of your respective course pages.
  4. Always design for 3mm mounting holes (3.2mm). You never know when you might need the PCB to fit inside a case that includes heat set inserts.
  5. Include your name in the top silk screening (and the ACES logo if our budget is participating :)\
  6. When selecting a font (vector, proportional, or fixed) vector is the preferred choice as it remains size-stable.
  7. The ACESTHTLegacy.cam file has been designed to fit well with the components found in the ACES_THT.lbr and ACES_SMT.lbr libraries. Please use this one to created the Gerber files from your .brd design.

UNO Appliances

  1. The term 'appliance', as it relates to a PCB that inserts directly into the female headers of a UNO, is a term I simply made up.
  2. The male headers of an appliance can by straight (the appliance would lay flat) or right-angled (the appliance would stand vertically)
  3. The issue of the facing direction for me comes down to balance. A tall design, with THT components that are relatively large compared to their SMT counterparts, can lead to stability issues. An inward-facing orientation is less 'tippy'.
  4. Access to additional supply and/or analog input pins is enhanced with an inward-facing design.
  5. You have to consider the total power draw of your appliance in your design. Digital pins can only source a maximum of 40 mA. For more than that, your appliance must access a 5V pin. From what I can tell, there are three accessible 5V pins on the UNO: one female 5V pin on the Analog side, and two male 5V pins on each of the two ISP headers.
  6. If you feel the need for your PCB to span both sides of the UNO, you may consider using the open-source UNO Rev3 Shiled as a starting point. EAGLE files for a varitey of designs canbe found. Here's one offering from Adafruit: https://github.com/adafruit/Adafruit-Proto-Shield-PCB

Breadboard Appliances

  1. Know the dimensions of the breadboard perfectly before you begin to lay out your board.
  2. For breakout boards, especially for the 8-pin DIPs, try to restrict beaking out the pins on ONE side, if possible.
  3. If you have to break out on two sides, make sure the header spacing is a multiple of 0.1"
  4. Two-sided breakout are tricky and can make it difficult to wire.