Controllable RGB LED system for your home or office

Step 2 LED System components

---

An LED system is comprised of several components. Let's take a moment to review those components.

1. The LED system needs a brain to control all those LEDs. This brain is usually a microcontroller such as the Parallax Propeller or SX or PIC or Arduino. This controller may cycle the LEDs using preprogrammed algorithms or change the LEDs based on an external connection to a DMX-512A system or serial (RS-232). We designed the Prop Blade controller for our specific applications of LED systems. The Prop Blade accepts 6V to 12V DC and has connections for both serial (via the programming header) and DMX-512A. In addition it has status LEDs for feedback and DIP switches and buttons for user input. You can get the Prop Blade as a kit from Brilldea if you want to use this controller. You are also welcome to make your own.

2. One or more LED driver modules is needed to control all the LEDs, after all a microcontroller only has so many I/O pins. To control this many LEDs, the microcontroller needs help so we designed the LED Painter. The LED Painter can control 16 channels of RGB LEDs. This means that we can hook up 16 pieces of RGB LED Ribbon, one to each channel, and control the color and intensity of each ribbon. The LED Painter is based on the TLC5940 IC from Texas Instruments. There is code available online for both the Propeller and Arduino for controlling this IC. You can also get LED Painter kits from Brilldea.

3. And of course, every LED system needs...well...umm...LEDs! That is right, lots of red, green, blue LEDs! We like the convenience of the RGB LED Ribbon we sell. The back side of the product has an adhesive on it so it mounts easily to surfaces. The LEDs and resistors are already assembled and it runs on 12V DC. Furthermore it can be flexed to mount on curved surfaces if needed. If you want, you could use your own LEDs. You don't even have to use RGB LEDs, you could attach 48 single color LEDs or 24 of one color and 24 of another color. Check out the LED Painter data sheet for more details.

4. All the equipment in the system would be for nothing if you didn't supply power. Yes, all these components need DC power. Our systems are designed to run on 12V DC. The quantity of LEDs in your system will dictate the amount of current your supply will need to provide. We used 12V DC, 5 amp supplies for our install and had plenty of room left over for expansion. If you want to be more precise, you will need to calculate the current draw of the LEDs you use in your system as well as the current needed for your controller and drivers.

5. Here are a few more items that complete the system:

• Cable and wire for distributing power and control signals.
• A computer and programming hardware for your controller. If you are using the Prop Blade which is based on the Parallax Propeller, you will want to purchase a Prop Plug from Parallax.
• Electronic and hand tools for assembling your system such as soldering iron, pliers, screw drivers, cutting tools and wire strippers.
• Any mounting hardware needed for mounting your controller, drivers, power supply, etc.
• A DMX-512A source, if you want to use DMX to control your LED system; this is optional.

6. Now that you have thought about the shape, space, size and look of your system, as well as considered the materials required, you can start pricing it. Your system cost will vary based on its size and what materials you may already have from past projects. If you have a microcontroller sitting around, then you might be able to use that. Remember to price the system out and to set realistic costs for the "non-trivial" items like connectors, ribbon cables, and AC cords because those costs can add up.

The following video shows an overview of our home LED system. This system was our first one created, so the hardware used in the system is a first revision. Brilldea's current Prop Blade and LED Painter are updated designs needed to accomplish a similar system.