48x LED (12x 4 clusters) for audio visual lighting. Advice please!

Projects General Guidance
1

Hi there, first post.

Been playing around with simple Arduino LED circuits for a few weeks, starting from basically no knowledge moving towards building a circuit for a lighting display project I am making. Just looking for some general advice/okay about the planned circuit.

Project details:

  • Total of 48x 3w LED's, externally powered and divided into 12x (4x LED in series), connected through 2 ULN2803's to 12 outputs on Arduino.

  • Digital input will be 12 frequency bands coming from Ableton live, triggering each set of 4 Led's at a certain volume.

Like I said, total amateur at electronics in general, but been making little ardunio led circuits in reality, plus some slightly more accurate ones in Tinkercad, which has got me to the stage of ordering what I think are all the necessary parts off the internet...

So I plan it to be very similar to the attachment, just with a 2x ULN2803's instead of individual transistors. And the voltage/resistors etc will of course be different, but this takes some figuring out as a novice so any advice on power supply size etc for this but with 3w led bulbs would be great!

Any help greatly appreciated as this will be going on show in a few weeks!

Will

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2

I'm missing specific questions.

Depending on the kind of your analog inputs it may be possible to connect them directly to the ULN2803 drivers.

A current limiting resistor is required for each series of LEDs. Again no more specific answer without LED data sheets. I'd guess that a 12V 20A power supply might be sufficient for the 3W LEDs.

3

3W LEDs need current controlled driver. They heat up, draw more current, and then burn out if the current isn't controlled. Simple resistor won't cut it.

This one might have enough current for your needs. If not, Digikey sells other that do.