How to control 3 or more 12v LED RGB light strips?


First of all this forum is AWESOME! I managed to get 2 RCG light ropes to operate independently thanks to this wonderful forum but like any guy... we always want more. :smiley:

So how do I approach this? I'm thinking 4 or 5 RGB light ropes and all flashing different times with different colours. Do I use a expansion board like shield to gain more inputs?

Here is my 2 LED Light rope set up. (Thanks to this forum) Neon Light Project 2019 - YouTube

I couldn't find any info on how to approach this due to my lack of knowledge of where to begin finding clues.
Thanks for the help in advance!


Do I use a expansion board like shield to gain more inputs?

Why do you need more inputs? If anything you need more outputs.

More specifically I would have thought you need more PWM capable outputs. You could turn your ordinary outputs into PWM capable outputs using a soft PWM library.

You don't need pwm pins if all you want to do is switch the lights on/off, which is all I could see happening in your vid. Any Arduino pin can do that.

You don't need pwm pins if all you want to do is switch the lights on/off, which is all I could see happening in your vid. Any Arduino pin can do that.

To expand on this, the analog pins can be used as digital outputs, or you can use a shift register to provide additional outputs. If you are going to he producing several of these, a nano or pro mini is usually preferred over an uno because of the size, and the ease of mounting to a custom pcb.

Hi folks,

Yes Grumpy, that's what I meant. bad.

Paul, this is where my knowledge is limited and I don't know how to approach this but you are right. I just wish to turn lights stips on and off like a old neon sign.

David, this sounds interesting! So how I'm approaching this is too cumbersome. You by any chance have some links to samples I can see?

Thanks for the waterfall of help as usual!!

So how I'm approaching this is too cumbersome.

We have no idea how you are approaching this, you have not told us very much.

Post a link to the strip(s) you want to use. Read the forum guide in the sticky post so you know how to post a link correctly this time.

Explain further what you want to achieve with these strips. You mentioned RGB, and I said you can use ordinary (non-pwm) pins to control them, which is true if you only want red, green, blue, yellow, cyan, magenta or white. If you want to mix any other colours, or dim them down from full brightness, then you will need pwm pins. Unless you are using leds with controller chips built-in such as ws2811/2812.

Hi Paul,

Right on that, I guess I did fail to provide enough info. So I'm using a weather proof WS2812B 5050 LED strip like this:

What I wish to achieve is alternate the individual light rope timing and colours to simulate animation. Kind of like an old school Las Vegas neon sign.

What I did in the past was use (Arduino UNO) digital pwm 4,5,6 and 12,13 & 14 to control RGB/timing to 2 light ropes. But I'm out of outputs to add more light ropes. If I need to start all over and approach this differently then I'm all open to that.


OK so my answer was right assuming you were just going to add an extra strip the same as you had before.

But now you want to use a totally different system. You drive those differently, to see how then read this page and the others linked to it.

Hi John, why do you refuse to read the forum guide so that you know how to post links? Look what Mike did. That is a link. You can click it. Mike was kind to you. Can you be kind in return?
Hi Paul,

Just figured it out LOL. I'm not trying to be rude and practice poor forum etiquette.

Hi Mike!

Back onto the topic.... thanks again for the tip! You've been such a great help in the past and keep up the great work brother!



John, thanks for that link. With this type of strip, one ordinary Arduino pin can control many strips, so your concern about Arduino pins is over. However, this type of strip needs a 5V supply with many Amps, depending on the number of LEDs in each strip. The PSU needs 1A for every 30 LEDs. Wiring them can also be tricky, because of the high currents. You must use good quality thick wires, possibly connecting the wires at both ends of each strip and in the middle also for longer strips. Read the link Mike posted, there are important components you need to use.

With eBay and many other links, remove the “?” and all that follows as they relate only to your search history.


OK, it’s still long, but more accurate. :grinning:

LOL Paul! :slight_smile: Got it and I need this refinement! If you were here I buy you a beer! Both Paul's that is!

So PaulRB, yeah I noticed the neopixel connection they speak is based on 5v. Mine are 12v so a different value of caps and resistors will be needed to make it work but I can see the theory is the same. Just need to order some parts and play with it.
Quick explaination.... I gave incorrect ebay link but LED light is based on same principal but quite a bit brighter. I use a 20 amp 12v distribution box I recovered from a old DVR surveillance project FWIW as power source.


I gave incorrect ebay link but LED light is based on same principal but quite a bit brighter.

So can you give the correct link because that statement sounds wrong.

Hey Mike,

Yeah I opened myself to getting shots here.. come on..bring it on guys! :stuck_out_tongue: LOL Seriously I was typing then got distracted (wife & kids can do that to a man), then I continued but had a couple things on my mind at the same time. Anyhow... after thinking things over... that ebay link provided a 5v 5050 led rope so why not go with that since I'm starting fresh anyways I thought to myself. So I reached out to that seller and will buy a small piece to play with. Carrying on with neopixel 5v samples maybe easier for me to start. Who knows I may like this better and can do what I hope to do? Will be a fun project!!


Yes it is just that a 12v system will be no brighter than a 5V system because the LEDs themselves are the same. It is just that you have to either waste more current or, as most 12V LED strips do, control three LEDs at the same time.

Well, I got a response from the 5v rgb neon light vendor and they only sell them in 1 or 2 meter strips. Bummer.... 12 volt it is since I have a few 1ft strips kicking around but will need capacitors to do this project. What's your guess I should try out in values before I hit the buy button?


but will need capacitors to do this project.

Well what is the difference between what you are planing to do now compared to what you did before?
Did you need a capacitor before?

For just on / off control normally the capacitors in your power supply are sufficient.

Hmm… you got me thinking again… what I dd before was use IRLZ44 mosfets to separate the 12v which powered the LEDs. Examples I found required this when connecting a 12v rope light to Arduino which operates on 5volts. I guess the coding for this is different from before so I maybe able to continue with what I did but allocate the signal line differently. Will think about this after (Canadian) Thanks Giving holidays. I’m on turkey duty so I must put the soldering iron aside and pull out my knives instead. :stuck_out_tongue: