There is two options for powering this device via the mains or from a battery source. I have designed it so both can be used if the other isn’t available. However I would recommend using the mains as batteries need to be replaced regularly. Since the Arduino and LED lights need a constant 5V supply once the batteries have drained to roughly 3.5V the lights start to fade and do not operate as designed. Also we used 4 cheap AA 1.5V which totals to 6V, meaning a voltage regulator is needed to protect the circuit. This regulator can get hot after sustained use, I believe this is due to the lights drawing 1.5 Amps. However for a small demonstration this is sufficient.

Therefor a more permanent and reliable source would be the mains. Taking a regular phone charger which safely steps the voltage down to 5V we have a power source for the Arduino to use. I would not recommend building your own. Usually there is live (Vdd), ground (GND), and two data lines (-D, +D) the latter two are not necessary for our application. Due to there voltage rating shown in Figure 1.0 (2.76V, 2.06V). Therefor these wires can be either trimmed shorter than Vdd and GND or taped up, to avoid a short circuit. For the example shown; red is power, black is ground, and the white and green wires are the data lines, however I would recommend confirming this is correct by checking the voltage from Vdd, D+ or D- to ground.

Figure 1.0; Schematic of a standard USB cable.

Figure 1.1: Above is 4 exposed wires. Red is power, black is ground, and the white and green wires are the data lines.

Figure 1.2: Schematic demonstrating how to power the Arduino and the LED's