Project Summary

Objective -

• Simplify the Arduino schematic and modify the layout to decrease the switching noise of a commercial Arduino.

• Learn from and analyze professionally created circuit schematics.

Strategy -

• To decrease switching noise, decoupling capacitors were placed in as close proximity as possible to Vcc leads of ATMEGA328.

• To decrease switching noise, large Gaps in ground plane were minimized (Continuous ground plane).

• To decrease switching noise, all return paths should be routed to seperate ground vias.

• Use Indicator LEDs and Switches to make debugging circuit easier.

Conclusion -

• Switching noise was decreased, sometimes by up to 15% on most rise/fall signals.

• Switching noise in some rising signals was similar to commercial Arduino. This was attributed to the fact that the rise time was slow enough to not make much of a voltage drop when the trace was acting as an inductor.

• To improve the design, I would improve the trace routing to result in less cross unders. I would also reduce the trace length of the clocks to the ATMEGA328 and CH340G.