Multi channel white LED tape

[richard]

Hello all

 

I feel I've seen this somewhere but I can't find it anywhere so maybe I dreamt it. I am looking for some two or three channel white LED tape where the LEDs are wired a/b/c/a/b/c/a/b/c etc - a bit like old battens of bulbs. This would let me do nice chases and twinkles without any complex control.

 

Does anyone know if this is made at all?

 

Thanks

 

Richard

[timsabre]

Never seen any like that. You can get white 5050 tape where each LED is made up from 3 white chips on 3 separate circuits.

 

However you could use digital tape which would do what you want, you can control each pixel individually then.

[DrV]

Never seen any like that. You can get white 5050 tape where each LED is made up from 3 white chips on 3 separate circuits.

 

However you could use digital tape which would do what you want, you can control each pixel individually then.

Can you get tape which has a much bigger pitch than you want and then use three strips side by side.

[ImagineerTom]

I feel I've seen this somewhere

There are tapes that have different temperature white LED's in them so that you can colour correct throughout the day; I'd be inclined to think this is what you've remembered.

Otherwise PIXEL tape / WS281 / Digital tape does come in a white version - random googled example https://coolcomponents.co.uk/products/apa102-digital-white-addressable-led-weatherproof-strip-60-led-4m

[richard]

Thanks - yeah the pixel tape is the obvious choice, but it tends to have issues with long runs and needs a more complicated controller.

[timsabre]

Thanks - yeah the pixel tape is the obvious choice, but it tends to have issues with long runs and needs a more complicated controller.

 

Plain RGB tape has problems with long runs as well though. How far do you need to go?

There are some good macro pattern controllers which will do that sort of pattern just using a few DMX channels.E.g. Enttec pixelator or digitaltape.co.uk "digitizer" (bias alert, I designed the 2nd one)

 

[ImagineerTom]

There's some amazing "single chip" controllers for pixel tape with inbuilt patterns that you can buy from all the usual auction sites for about £2 and just plug straight in to the tape. Even if you do have to program up the controller yourself it's not especially difficult and there are plenty of off the shelf controllers available and a thriving arduino community for pixel tapes. An hour of your life either choosing an off the shelf unit or cut-n-pasting sketches in arduino would give you a dependable controller with the chases of your choice.

 

With regards to length - you couldn't sensibly drive more than 10m of "dumb" LED tape without repeaters/boosters; it's virtually the same for pixel tape.

[timsabre]

That's a good point about arduino, there's some great ready-made libraries out there to do it.

The trouble I've found with the ebay type pixel controllers is that it's all steppy steppy 7 basic colours. If you want anything fading or any subtle colours then you seem to need to get a more complicated controller, which is a bit daft really.

 

[richard]

I've found that neopixel driven from an arduino (I've built my own ESP8266 based artnet/wifi nodes for it before) is unhappy with lengths aboev about 3m even when driven from both ends - the middle goes very dim. I could wire in additional pickups but it's a lot of work! ideally I would get about 10m out of it so I'd be interested to know what neopixel tape will do this without problems..

[ImagineerTom]

If the middle of the tape is dim but otherwise responding correctly then you have power issues not controller format issues. Every digi install I’ve ever done it for (and admittedly it’s not millions) I’ve just spliced in power every 5m and never had problems with brightness- I am always surprised at just how much power the tape draws though.

[timsabre]

If the middle of the tape is dim but otherwise responding correctly then you have power issues not controller format issues. Every digi install I've ever done it for (and admittedly it's not millions) I've just spliced in power every 5m and never had problems with brightness- I am always surprised at just how much power the tape draws though.

 

Agreed, it is not the controller that is the problem.

 

The power tracks on the tape are really weedy. If you are doing full white (everything at 100%) then you will get problems earlier than 5m, normally it all goes a bit pinky because the red continues to work at a lower voltage than the green or blue do. If you need to go 5m then reduce the brightness.

 

[richard]

This was side emitting RGB tape (possibly even RGBW) and so thin, as I say it does the job but is just a bit complex for the use I am looking for in this case

[TomHoward]

I'm fairly sure I did once have a delivery of eBay variant of tape, that was an old school RGB tape (with separate R, G and B Leds), but of the white variant where they just populated all three with white, so it gave three-circuit tape and you just shorted three of the pins together.

 

On a side note we use replacement 203W Xbox power supplies for LED tape, they are basically a cased up ATX power supply and output about 15A at 12V for usually under £20.