Hello there Arduino fans!
Christmas is closing up, and i've decided to make some lights for my christmas tree.
The idea is simply to have multiple LEDs in the tree, and be able to make them blink and fade.
I believe i will be using 16 LEDs.
Everything will be controlled with an Arduino uno.
So this is the idea:
Put the LEDs 8 and 8, creating two lines controlled separately.
Make the LEDs blink without relays, as they make that annoying clicking noise.
Make the LEDs fade (another reason not to use relays)
Run it with a standard wall adapter
My problems and solutions:
Should i connect them in series or parallel?
If i connect them in parallel and one LED burns out, will the other LEDs receive higher ampere? - Adding a resistor to each led would prevent this.
You are controlling each one individually?
Wire them to a WS2803, can fade each up & down at will independently.
Two sets of 8, each set performing as one?
Run 5-6 strings of 3 in series from 12V. Use ULN2803 to sink current, with PWM outputs driving the ULN2803 inputs. Need a current limit resistor per string.
Hey!
Thanks for the answer!
Your suggestion with the ULN2803 seems good, though i'd really like to have only one small cable, not many small or one big.
Correct me if i've missunderstood your answer
Use ws2812B leds. You can string all 16 leds (or as many as you like) in a single string with only 3 wires. These leds can not only be controlled individually with no extra chips, but they can fade and change colour! They will make amazing tree lights!
Get a 5V stabilised/switch mode wall-wart power supply with enough current to run all your leds and the Uno too. The rating needs to be around 1A for every 15 ws2812b leds, plus a tiny bit more current for the Uno. The leds are usually sold in tens, so make a 20 long string and use a 1.5A supply.
