Electronic Dice
My freshman year was the first time that I ever had a circuit board fabbed.​ It was a simple design but taught me important lessons about PCB design and attention to detail.
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At that point, I hadn't realized each resistor needed its own footprint, an obvious mistake looking back. I thought that the limiting resistors could simply fit in the same holes as the IC pins that they connected to. Since I had also connected traces between the pins, the resistors were shorted and the LED's burnt out on my first board.
This PCB also taught me that a single component, such as a MOSFET, might have multiple packages. Package MOSFET-A might have a different pinout than MOSFET-B leading to incorrect PCB schematics.
 Step 1 The first circuit board that I ever had fabbed... When originally making the circuit design, I breadboarded the circuit to test functionality. |  Step 2 After confirming the breadboard design, I used OrCAD Capture to create a circuit schematic. This is the top of the blank circuit board that I had fabbed. |  Step 3 The underside of the same circuit board. |
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 Step 4 My first working PCB! |
The final design has three buttons...
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Roll: Activates the 555 Timer which continuously activates the 7490 decade counter. The decade counter BCD value is converted to 7-segment display using the 7447 IC.
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Light test: Used to test that all 7 segments light up by activating the "Display Test" pin the 7447 IC.
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Hide Roll: Activates the "Blank Output" pin on the 7447 IC to make sure that a user doesn't try to predict the roll.