Microcontroller:

• Design of a custom portable light stick with programmable pattern based on a ATmega328P, programmed by a FTDI chip (You will need to burn the Arduino boot-loader first using the SPI connector J6).
• There is additional input/output connected to the analog pins of the ATmega if you want additional control, like buttons, ...
• On my first version I've added a 0.1uF cap (C4) to ground on the reset pin. It must not be assembled since it messes with the FTDI DTR. I've removed it from the BOM and Centroid files so it shouldn't be assembled.
• You can download the full schematic below

CAD:

• An example of CAD enclosure for the electronics are given in the project but feel free to design your own if you want.
• Additionally, I'm using a 200mm x 10mm x 10mm square aluminum tube to mount the LED.
• For assembly, I've linked the OnShape project link for everyone to view the assembly for help if needed

Wiring:

• To save some space each module board is connected to the others using soldered wires. It's not optimal for debugging and disassembly, which is why I'm working on a V2 with facing connector (like dupond connectors) to get rid of cables.
• Some connections are missing out of the box, it apply for components marked DNP (Do Not Populate) or 0R (0 ohm). It is for debug. For normal use you must add 0 ohm resistors on the 0R footprints and leave empty the DNP.

Other:

• The charge current of the Li-ion battery is set to 500mA to be compatible with standard USB current. I didn't place any fuse in series with the battery. I recommend adding a external 500/750mA fuse for safety. I'll probably add a resettable fuse (like the one on the USB input) on a V2 of this project.

• The buck-boost converter used in this project is design for a maximum output current of 500mA.