LED Constellation Board for Beginners

Build a constellation of LED lights in this introductory circuitry activity. Taught at the beginning of the physical computing class, ATLS 3300, at the University of Colorado, Boulder ATLAS Institute.

• Adafruit Circuit Playground
• ThreadBoard as described here
• 5 or more LED lights
• Stainless steel conductive thread
• 4mm x 3mm magnets as needed
• Power source (battery or USB)

Identify the pads on the Adafruit for the ground (GND) and the source (3.3 V). To make connecting the thread easier later on, place a magnet on top of each of these pads.

Take note of the lengths of the metal legs on the LEDs: the longer leg has positive polarity while the shorter leg has negative polarity. Splay these legs out and place them on the board with the longer leg facing outwards and the shorter leg facing inwards towards the Adafruit.

Lay out threads on the board to act as power and ground busses and allow for parallel connections.

First lay out the ground bus. Connect one end of stainless steel thread to the magnet on the GND pad and circle it around the perimeter of the pad. The shorter legs of the LEDs will connect to this thread, so ensure that the LEDs are positioned above this ground bus.

After this, lay out the power bus. Connect one end of thread to the 3.3 V pad. If the thread crosses over the ground bus, place some fabric or some other non-conductive material over this area to avoid a short circuit from the overlapping ground and power busses. Wrap the power bus around the outer perimeter of the board. The longer legs of the LEDs will connect to this thread, so ensure that the LEDs are positioned below this power bus.

Connect the Adafruit to a power source. Using small pieces of thread, connect the positive legs of the LEDs to the outer power bus and the negative legs to the inner ground bus. If the LED legs and bus threads were aligned correctly, the LEDs should begin to light up with each connection.