Golden Arduino
Overview:
The objective of this lab is to design a superior "Golden Arduino" board that outperforms the commercial Arduino board, specifically in terms of signal integrity. We will achieve this by implementing advanced design practices such as utilizing a common ground plane, placing decoupling capacitors as close to the IC as possible, minimizing trace length, reducing trace parasitic inductance, and incorporating effective power filters. These design improvements will contribute to enhanced performance.
The main features of our Arduino board will include the ability to upload code via a USB port, support the Arduino IDE, and ensure full compatibility with most Arduino Uno R3 shields. By combining these features with the aforementioned design enhancements, we will deliver a superior Arduino board that provides exceptional signal integrity and overall performance.
PCB schematic
PCB layout
bare PCB
Back of PCB
first PCB revision second PCB revision
quiet high and quiet low trigered at the falling edge of the golden and commercial arduino
golden arduino commercial arduino
table comparison of the percetage of noise decrement acomplished compared to the commercial arduino
key takeaways:
● Proper layout practices greatly improve switching noise on the power rail and ground
bounce.
● Good or bad layout practices can greatly affect near-field emissions.
● The reset line must receive appropriate power to enable bootloading.
● A 16 MHz crystal must output the desired resonance only after boot loading has
occurred.
● Testing the tvs chip output is clamped to the desired voltage level is always
recommended to ensure successful code upload in this case output of the data lines.
● A 12 MHz crystal must output the correct signal for CH340 correct upload to occur.
● Data D+ and D- lines should be opposite of each other.
● Repercussions of a slammer circuit can be mitigated by good design practices.
● Don't blindly follow a design that may include legacy components that aren't the best
option.
● Tx and Rx lines are easily mistaken, so double-check their placement.
Conclusion
the Golden arduino showed a much better performance in terms of switching noise, quiet signals, power rail noise, and near field emissions compared to a commercial Arduino.
