Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [rgb]

Short for: Red Green Blue, the primary colors in light. They can be mixed to create any visible color of light. Questions are typically in reference to RGB LEDs, RGB LED drivers, and code related to mixing RGB light, but can include the RGB Video Standard in VGA monitors.

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Why can't RGB or bicolour LEDs produce a decent yellow?

I have several different RGB LEDs and bicolour red/green LEDs, from different suppliers. I find that, with the appropriate resistors, they can produce a perfect orange and cyan; and a barely acceptable magenta. One thing they cannot produce,…
Sod Almighty
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Why are the three component LEDs in an RGB LED so unbalanced?

I was recently spec-ing some RGB LEDs for a project, when I noticed that the millicandela ratings on the three colors are rarely close to the same number. (i.e. 710mcd Red, 1250mcd Green, 240mcd Blue). Does this cancel out somehow, or does this mean…
Tustique
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What makes a good RGB LED

I am looking for supplier for RGB LEDs for an upcoming project RGB POV LED Globe. Normally I would go to my local electronics supply story, but this project requires lots (~1000) of LEDs and my local electronics store charges a premium for the LEDs,…
Steven Smethurst
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Why does a resistor in my Neopixel data line work at all?

Adafruit's best practices for their Neopixel LED strings say, "Place a 300 to 500 Ohm resistor between the Arduino data output pin and the input to the first NeoPixel." Someone asked about the purpose of that resistor here and I'm reading about…
user358829
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Why do some RGB LEDs have six legs?

Others have four legs, which makes sense to me, as ground can be shared. One of many examples of a six legged RGB LED is the Kingbright KAF-5060PBESEEVGC.
feklee
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Controlling an RGB LED color range from an analog temperature sensor (no Arduino, etc.)

I'd like to combine an analog temperature sensor with an RGB LED so that I get a range of colors based on temperature. Low temperature blue, high temperature red, with color fade between them as the temperature changes. For sensors, perhaps…
Tim Holt
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Hooking up multiple RGB LEDs while using a minimal number of PWM pins on an Arduino?

I currently have an anode RGB connected to the 11, 10, & 9 PWM pins on my arduino. However I would like to add 3 more LED's to my project, but I don't want to necessarily take up every single PWM pin (I still want to attach a shield). Is there a way…
VAlexander
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Red Green Blue LED

Do you need to use different resistors against each of the colours on an RGB LED?
mad_z
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Is there a single IC that can control a 8x8 RGB LED Matrix

I was wondering if there was a single IC like the MAX6960 that could control a whole 8x8 RGB LED Matrix because the MAX6960 can only control a RGY.
GLaDOS
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My DIY RGB LED panel powered by 9V battery works but certain colors like blue, white, and purple don't work

I am able to power on my LED unit here with a 9V battery. I'm using a recharble lithium 9V as well. I can't figure out why I can't get blue, purple, and white. The only colors I get are red, orange, yellow, and green. The LED panel is normally used…
Destructo
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POV globe speed questions

I am planning on creating a RGB LED POV globe only physically larger then that one. I am planning on using 64 RGB LEDs, requiring 3x pins per LED for a total of 192 outputs. Obviously I am going to need some shift registers. I have looked in to…
Steven Smethurst
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RGBHV (VGA) to YPbPr Converter and Waveforms?

Purely for hobby, I am working on an RGBHV (VGA) to YPbPr (Component) converter circuit for old games consoles modified to output RGBHV on a VGA cable. From the game consoles, the RGB signal is taken from before the composite encoder chip and the…
Lt.Derpington
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Digital RGB interface EMI filtering

Consider the following system: where: The motherboard contains a LCD controller (SSD1963 from Solomon Systech) and other components (application processor, solenoid drivers, power supplies, etc.) The display board contains a white LED backlight…
johsey
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RGB LED - Set intensity on Red and Blue

I've recently purchased SparkFun's starter arduino kit, which comes with a 4-legged RGB LED. If I understand correctly, this RGB LED should be able to access the full range of RGB colors, with 255 values on each red, green, and blue. I've wired up…
jwegner
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What resistor to use with this RGB LED?

i have this led, and im not sure what resistor to use to drop the 5v current to an appropriate voltage and produce the appropriate current. the LED is rated at 200mA, but the data sheet says i should apply 150mA through it. my micro-controller…
stackOverFlew
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