Short for: Red Green Blue. The primary colors in light. Mix them to create any imaginable visible color of light. Questions are typical in reference to RGB Leds, RGB Led drivers, and code related to mixing RGB light, but can include RGB Video Standard in VGA monitors.

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2answers
191 views

LED circuit is draining AA batteries REALLY fast

My question is long, rambling and weirdly specific. I hope I'm not violating like 50 stackexchange rules, but I'm completely lost. Long-time lurker, first time asker and pretty new to circuits in ...
0
votes
1answer
50 views

How to control a common-cathode RGB LED matrix with Arduino?

I have the Arduino Uno board, and I want to create a 17x31 RGB LED matrix. Unfortunately, I wasn't patient enough and already bought the LEDs, and I purchased common-cathode LEDs without doing much ...
0
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0answers
24 views

Help with driving rgb leds with modded PC case (hdd activity, pwr buttons, led strip)

I have a custom home pc / server mini itx case (2 computers in one case), which is still project in progress. I have created individual hard drive activity leds via this circuit and it's been working ...
0
votes
1answer
35 views

Can 5630 SMD on LED strips be RGB?

Hi I've been trying to look online for RGB 5630 LEDs strips but I can't find any. All the strips I've found carried 5050s which give a max of 1020 lm/m more or less.. Any idea if strips carrying ...
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3answers
66 views

Multiplexing 2 times 4 CC RGB LED's

I need to make 2 sets of 4 Common Cathode RGB LEDS. In each set of 4, every led must be individually addressable. It doesn't matter if both sets have duplicate outputs or not. (Although optimally they ...
1
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3answers
64 views

Diode destroys square wave?

I was developing a footwell controller for my car, using RGB LEDs for the lights, an Arduino Nano for RGB controlling and an auxiliary PWM generator (pure white lights) when the Arduino is off. The ...
2
votes
0answers
98 views

Long term reliability of addressable RGB LED strips? How do WS2812B, APA102, and SK6812 compare?

I'm about to order a lot of RGB LED strips for a project that will hopefully be running for years if not decades. I used to have very good luck with strips using the WS2812B chips, but in recent ...
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2answers
77 views

Why is my RGB LED not working with arduino? [duplicate]

I have an rgb led with a common annode connected to my 3.3v arduino mini pro in the following way: simulate this circuit – Schematic created using CircuitLab When I try to illuminate ...
0
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1answer
69 views

Please review my board design

This is a follow up to my question from yesterday about my schematic Please review my RGB Controller I've fixed the incorrect DC jack component that was present in my previous question, along with ...
1
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1answer
53 views

Please review my RGB Controller

First off, I just want to say that I'm still pretty new to PCB and schematics design, and electronics in general, so any suggestions on improvement are much appreciated! I'm creating a basic circuit ...
0
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0answers
72 views

LCD interface with Xilinx- XC95288 controller board

I have to interface 24RGB LCD interface with Xilinx XC95288 board. On Xilinx XC95288 board, it has LVDS pins available for interfacing LCD. I am using SN75LVDS86A to convert LVDS pins of controller ...
0
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1answer
102 views

RGB interface with MCU

I am referring 7" LCD (P/N : S070WV20-CT16) for interface with host controller LPC1769. Datasheet Part of datasheet I've added here: TFT has data pins ( R0-R7,G0-G7,B0-B7), Control pins ...
1
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1answer
69 views

Use an Arduino to control a 12v rgb strip

I am wishing to use an Arduino UNO to control a 12v RGB LED strip. Can I use a transistor instead of a relay? The LED strip has 4 pins: + , ...
0
votes
1answer
97 views

RGB LED Driver (with PWM) not working as expected

I'm working on an RGB LED project for which I have designed a driver (Original Design). Everything seems to be in place but there is some problem that is causing the Drains/Output to be always High ...
24
votes
4answers
2k views

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 ...
1
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2answers
148 views

How to feed custom RGB Led keyboard backlight

I have found a lot of topics but none of them describe what I want to use it for. Basically I want to put 104 RGB Leds under my laptop's keyboard and be able to control them individually. The ...
0
votes
1answer
49 views

Power for Strip lights

How many watts does a 12v 300 led - 5 meter strip light use roughly, is there a wattage per smd/led there 5050, I have a 5amp 12v = 60watts I think and was told that's more than enough, and I have a ...
0
votes
1answer
115 views

A led mystery ? how to connect? [closed]

We have ordered from a supplier some high power leds - 20W RGB. They dont have any data sheet , and so we where thinking that we would try and find quickly how to ...
1
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0answers
283 views

Can I connect a single color LED string to a RGB DMX512 controller?

I am planning on doing a bit of a light show this christmas on my house, I have ordered a bunch of 5050 RGB LED Strings, DMX controller, DMX Bridge and will be running the show using Vixen software. ...
0
votes
1answer
93 views

tricolor single package LEDs do not have same intensity for each color, why?

LEDs that have 3-in-1 RGB capability where each is driven independantly of the other usually contain three seperate LEDs in a single package. Each of them is made using different material to get ...
0
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1answer
115 views

Converting RGB composite output to VGA

We've got an old Arcade machine at work that we're busy converting to being powered by a PC running an emulator. The controls have now been sorted, and audio should be a breeze. Remaining is hooking ...
0
votes
1answer
110 views

How do I measure the output voltage of an RGB LED controller?

I want to replace an RGB LED controller (much like this one) with my own MCU. Therefore, I think I need to know what voltage(s) the RGB LED controller outputs so I can make my MCU/component have the ...
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0answers
118 views

can't change LEDs states using PCA9685

I have a PCA9685 IC connected to i2c of cubieboard like board. Also OE pin is connected to one GPIO pin. I'm using ic2tools to communicate with PCA9685, I can ...
0
votes
1answer
81 views

High Power RGB Led control

We have got a 20W led ,RGB from a good seller in China. I have a few questions regarding the led (see the attached image) Is there a data sheet to this Leds? something generic ? How can you know ...
2
votes
2answers
648 views

how to get the RGB value of a color using phototransistor or photodiode?

I'm making a color analyzer which can measure Red, Green, and Blue portions of a color (ex: 128,255,0).I'm not supposed to use pre-made color sensors and need 1% ACCURACY. I used three LEDs - R,B ...
0
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2answers
244 views

Arduino - Controlling 8 RGB LEDs (beginner question)

First time poster here. I have an Arduino Uno project that will require 8 RGB LEDs to be controlled. They will be turned on and off with pushbuttons, cycling through red, then green, then blue, then ...
1
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1answer
379 views

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 ...
0
votes
1answer
210 views

WS 2811 lights flickering

I'm working on a project involving a bunch of daisy-chained WS2811 lights and I'm noticing significant flickering on the ones at the end (lights #16-30 in a chain of 30). Right now, the circuit is a ...
2
votes
1answer
229 views

how to measure RBG values of a color using phototransistor

I am developing a circuit which can measure RGB values of a given color. I have used LED to transmit light and reflected light is filtered by 3 R, G, B filter papers. Earlier I used LDR and found that ...
0
votes
1answer
297 views

Use 4-pin S-video cable connector on RGB LED?

I'm hoping to make some 4-pin RGB LEDs (R, G, B, GND) easily hot pluggable, so I'm wondering if 4-pin S-video connectors could be used. Now, 2 of the pins on a S-video connector are GND, so would ...
0
votes
2answers
202 views

LM317 and PWM grounds

I have a question regarding the LM317 and PWM. My circuit receives +12v and has three grounds (R,G,B) that are PWM. I need to drop the voltage down to 3.2 volts from the 12 volt source. NOTE: I know ...
0
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2answers
173 views

10 3W RGB LEDs in series control current

I'm having the following schematics connected to a 5V 25A DC power supply. All LEDs are 3W RGB, additional values are. R1: 6.8 ohms 1/2W R2: 4,7 ohms 1/2W R3: 4,7 ohms 1/2W I'm using an Arduino Mini ...
2
votes
2answers
2k views

LDR + RGB Led = Color sensor. How to calibrate it?

1$ color sensor. My adventures in electronics continue. While talking with a friend about colors, he told me about color sensors. Later I remembered the video where they sort smarties and so I ...
2
votes
2answers
255 views

LED hub purpose?

What is the main purpose of LED hub, is it used only for RGB matrices to connect shift registers for every color or there are some other applications? I'm working with HUB75 and that is the reason ...
0
votes
1answer
1k views

Multiple LED's, one controller, diagram included

I want to make sure that my logic is correct and this would work. I'm trying to control 5, 16.4' LED strips of 5050 RGB SMD's at 60 LEDs/m or 300/strip. I want all of them to be ran off the single ...
1
vote
1answer
74 views

RGB matrix displays?

I'm working on firmware for LED display composed of Chinese RGB LED matrix modules (1/4 scan, 16x16, RGB). I want to find out how some pictures are displayed in three colors, is there any idea behind ...
0
votes
2answers
266 views

How does a PC detects a VGA monitor?

Currently I am trying to connect my LCD to my laptop through a VGA connector. The LCD has 6 wires out of it which I am trying to solder to a VGA male connector, But the laptop doesn't detect the LCD. ...
0
votes
1answer
75 views

Can use 17 resistors with 16 rgb led's?

I always see an rgb led ran with 3 resistors, for example a 20ma led on 5v power uses 150ohm's for red due to it's lower voltage but only 100ohms for green and blue. I am running 6 shift registers off ...
1
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4answers
274 views

Minimizing PCB size of a 192 RGB LED array

I'm working on the design of an LED lamp house for my film scanner. I need RGB LEDs, plus IR LEDs. I'm figuring on a 2"x2" grid of SMD LEDs. Datasheets for the ones I'm using below. The current design ...
0
votes
1answer
214 views

Splitting Digital RGB Signal Line to multiple LED strips

I am trying to connect multiple strings of WS2812B RGB LEDs to the same signal line (so that they will all behave the same way, display the same colors, etc). The WS2812B is very time sensitive, so I ...
1
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1answer
240 views

Controlling multiple RGB leds with PWM from a Atmega328P using one transistor per color

I want to be able to control 9 RGB leds, each color from a potentiometer. Each color needs 20mA, so when all the colors are present the leds will need 540mA (9*3=27, 27*20mA=540mA). My RGBs leds are ...
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votes
1answer
163 views

What kind of IR controller is required to drive a 15m LED strip?

I have to light a 15m RGB LED strip but I don't know how many amps the IR controller (sensor) is required to drive. There are three LED strips, each 5 metres, and I need to connect them together ...
2
votes
1answer
215 views

How to calculate image brightness for use with LED panel

I am using a 64x64 RGB LED matrix for which I'm preparing some content. The existing firmware reads RGB888 video files. I'd like to analyse these files before uploading them, to make sure the overall ...
1
vote
2answers
165 views

Change RGB leds intensity?

Sorry if this is too basic but I don't understand this issue. Right now, using an MCU, I change the RGB colours of an LED strip with 3 PWM signals. All colours works great . The thing is, when I am ...
0
votes
2answers
289 views

0.5m of RGB LED strip light with micro RGB controller powered by 12v li-ion battery pack?

my questions are all pretty basic but I'm very new to electronics and could really use the help. Ill try and be as specific as possible and would appreciate any advice. Abit about me - Im UK based ...
1
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1answer
105 views

rgb led current limit

I am working with RGB LED, my question is will it burn up / get damaged I have already chosen resistors proper for each color of R G B to draw 20mA, but running R G and B at same time draws lots of ...
0
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1answer
421 views

Driving a RGB Led strip with a RGBW controller

I have a RGB LED strip (Common +) that I want to drive using a controller that expects the strip to also have a W (White) channel. So what I am basicly looking for: As soon as the controllers W ...
1
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1answer
1k views

powering 12V 5m/16ft 5050 RGB LED Strip with 16V power adapter?

I'm new to the forum found this using google. i have 2 (Two) 5050 RGB 12V LED Strips that are 5M/16ft. It's not as bright as i'd hoped it would be. I double powered one of them with the cheap power ...
1
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3answers
797 views

Why must resistors be on the respective anode terminals instead of the common cathode terminal of a RGB LED?

Different from the best answer of this one: Why does a resistor need to be on the anode of an LED? But well, I'm also an electronics noob ^.^ Recently I bought the official Arduino starter kit and ...
1
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2answers
389 views

Show different colors using RGB LED strip and Arduino

I am a beginner, I am following this post to program RGB LEDs (smd 5050). I want few specific LEDs to glow in specific color while other LEDs are glowing in other color. Need help in doing this. I ...