This project is an extension to the Speech Recognition with Arduino by leandro4b (https://www.instructables.com/id/Speech-Recognition…). However, instead of using 3 separate colored LEDs, I used a multicolor 4-channel RGBW LED Emitter. I had the opportunity of working at LED Engin last summer, which is why I was able to use the high power 4-die RGBW emitter ( LZ4-20MD00) for my project. You can purchase their RGBW emitter from Mouser here. I also got a lens that is paired with the emitter. This allows the colors to blend better, but it is optional for this project
The idea is simple: I want a voice activated LED program that allow me to change the color by modifying the amount of red, green, blue and/or white LED in the emitter. In addition to that, I wanted some preset functions where I can tell the light to "wake up", "go sleep" or display the colors of the rainbow in order.
How this works: BitVoicer (voice recognition program) takes in a voice input, recognizes it and transfer that into a string. Every time it calls that particular string, the Arduino program will tell the LED what to do.
For this project, I used:
When I got the emitter in the mail, It had no wires on them. The nice thing about the LZ4-20MD00 is that the LED is mounted on top of the MCPCB, which allows us to solder wires onto the LED more easily. There are 8 pads on the MCPCB- the data sheet tells me which pad is for which wire. I actually had some challenges while soldering the wires onto the MCPCB because the MCPCB sucks the heat away, making it difficult for the soldering iron to heat up the pads. I then realized that the data sheet actually had tips for soldering. For this particular emitter from LED Engin, I had to heat the emitter up with a hot plate to 125-150 degrees C before soldering the wires on. Caution: different manufacturers have different procedures for attaching the wires- make sure you don't overheat the emitter.
According to the data sheet (on pg. 7 and 15), these are the wires connected to each pad:
Pad 1: White Anode +
Pad 8: White Cathode -
Pad 7: Red Anode +
Pad 6: Red Cathode -
Pad 5: Green Anode +
Pad 4: Green Cathode -
Pad 3: Blue Anode +
Pad 2: Blue Cathode -
I suggest that you use colored tape to indicate which wire is for which color so that you don't get confused later on.
Since this is a high power LED, I needed a heat sink for the emitter so that the LED does not overheat.
I made a simple heat sink out of aluminum and attached it to the LED Emitter using screws.