Not sure if simple LED coffee table.

[joburg]

Hi people, my first post.

I have this crazy idea of making a LED table which consists basically of 9x9 square boxes, each row of boxes emitting a different colour to produce a gradient along the table, as such:

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Im fairly confident I could pull this off with my limited electronic know how (did some as part of a civil engineering degree)

However, the kicker is, I want the colour gradient to kinda move along in a direction. So each row would slowly change colour at a slightly different phase to the ones either side.

So my question is, not having a whole heap of knowledge, pretty much what do I need to pull this off. I have been looking into micro controllers, but its hard to get info. Will I just need 1 microcontroller with at least 9 RGB outputs? What are some recommended brands? Is this going to be a total ***** to program? Will 1 RGB output have enough juice to power a whole row of 9 RGB LEDs, or will I need to boost it somehow?

Any suggestions or advice would be greatly appreciated.

 

[upand_at_them]

You should probably start with Nigel's tutorials. See the sticky in the Micro Controllers forum for tons of info. I don't know why you were having trouble getting info.

If the LEDs in each column are going to be lit together you can connect them in parallel and drive them from a transistor, 9 transistors in total...easily doable with any PIC with enough outputs, 16F628 and 16F88 are good. Start with something simple, get a microcontroller and program it to light an LED.

 

[joburg]

You should probably start with Nigel's tutorials. See the sticky in the Micro Controllers forum for tons of info. I don't know why you were having trouble getting info.

If the LEDs in each column are going to be lit together you can connect them in parallel and drive them from a transistor, 9 transistors in total...easily doable with any PIC with enough outputs, 16F628 and 16F88 are good. Start with something simple, get a microcontroller and program it to light an LED.

Thanks. Im probably having trouble because I dont really know where to start. Its hard to research information on something when you dont know what information there is.

I will definately have a go at Nigel's tutorials.

Thnaks again!

 

[audioguru]

Each square will probably need its own LED or two to light it. Then you need 9 red LEDs by themselves, 9 more red LEDs combined with 9 yellow LEDs, 9 yellow LEDs by themselves, and separate and combinations of the remaining colours. That is a lot of LEDs.

 

[Hero999]

I think he wants an animated rainbow.

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[bryan1]

Just for a laugh I decided to Google
for led coffee table and the results from that link speak for themselves....

Cheers Bryan

 

[MrDEB]

Would think he needs more LEDs per square for enough brightness. A uln2003 sounds like maybe the answer.
Using PWM is perhaps the second key.
Suggest getting a PIC programer, a bread board, some LEDs. Just get 9 LEDs working THEN worry about the number of LEDs and how to derive them.
You could even get advanced and add several routines so the LEDs come on in various patterns with the touch of a button.
If all you want is to fade from one color to the next then I recall a RGB circuit that fades using a 4023, 555 and several transistors but the PIC is the best way to go.

 

[MrDEB]

found link. I started playing with this circuit but found micro-controllers. Just add more stages but would cost more than using a PIC
bit-tech.net | Rainbow LED

 

[audioguru]

Many ordinary 25mA LEDs are so bright that they blind you if you look directly at them. The coffee table is not supposed to light a stadium nor light the room. So diffused and dimmed LEDs will be fine.

 

[blueroomelectronics]

The OP will also have to learn about microcontrollers.

 

[audioguru]

found link. I started playing with this circuit.
bit-tech.net | Rainbow LED

It operates exactly like some of the solar garden lights I have. The LED has the 3 colours inside and also has the driver electronics on a tiny chip inside. The LED is the same size as an ordinary 5mm LED, has 2 leads, shines over a wide angle of about 140 degrees and is pretty bright.
Its pattern is (ho hum, yawn) boring because it repeats over and over and .....

I made some RGB Mood Lights many years ago with a dual opamp for each colour making its LED slowly brighten then fade by a triangle waveform. The oscillators ran at slightly different frequencies so when the colours randomly add they make millions of slowly changing different colours and brightnesses. Occasionally they produce pure white then sometimes they are all turned off at the same time for a moment. They light the ceiling at night.
Most Mood Lights today use a micro-controller.

 

[danrogers]

If he does not wish to have it animated, could he not just use something like superflux rgb leds, then work out how to get each desired colour by current limiting each separate chip in each led?

 

[MrDEB]

Yo Audioguru, I would be interested in your mood LED circuit as I was planning on using the link I posted for my Cabinet lights but your description sounds better.

 

[audioguru]

This circuit is similar to my Mood Light circuit. A few resistors must be changed a little to match the different voltage of different colour LEDs. The frequency will probably be different for three of them because the electrolytic capacitors have horrible tolerance of their values.

 

[MrDEB]

Thank You Audioguru

 

[burton2663]

why dont u just use a 10 led sequencer, or a running light effect just string up a number or leds per row or column