This cycle occurs at 490 Hz, 490 times a second, and you can control this duty cycle with AnalogWrite.Ĭonnecting potentiometers to control the RGB LEDs A 50% duty cycle means the output is high 50% of the time and low the other 50% of the time. The intensity of the LED is determined by the PWM duty cycle, this is how much time the output remains on. PWM turns the output on and off periodically, and how long the output remains on determines the brightness of the LED. How bright an LED shines is controlled by how much current flows through it, but we cannot directly control the current as the Arduino Uno lacks fully analog outputs, to control its brightness we’ll be using Pulse Width Modulation (PWM). If you don’t have a multimeter you can do this with the 5V and GND pins on the Arduino, just make sure that you have a 220Ω resistance in your circuit. If not, take the positive probe to the common pin and the negative probe to any other pin, the LED should light up meaning it is common anode. To test this take the negative probe to the common pin and the positive probe to any other pin, if the LED lights up it is common cathode. The only way to tell if your RGB is common cathode or common anode is to test the LED, I would recommend testing with a multimeter using the diode function. In this example, we’ll be using common cathode LEDs, if you happen to have a common anode RGB LED the wiring and outputs will have to be inverted. In common cathode LEDs the longer pin gets connected to GND and its components are lit by a 5V signal, in common anode LEDs it’s the opposite: longer pin goes to 5V, a 0V signal turns components on. RGB LEDs come in two types: common cathode and common anode. I previously mentioned common cathode and common anode LEDs. Source: LEDsupply Common Cathode and Common Anode RGB LEDs Note that this is a common cathode LED, in which the longer pin is connected to ground, further ahead I’ll explain what common cathode means.Ĭloseup of a surface-mount RGB LED. This wiring diagram shows you how to connect an RGB LED to the Arduino board. Instructions Step 1 – Connecting the RGB LED I wouldn’t recommend these, I prefer the flexibility of using resistors, and some reviews show poor colour reproduction when using RGB values. These modules don’t allow for any flexibility while building the circuit, but they are more plug-and-play than their alternatives. You can also find RGB LEDs in KY-016 modules, which have the LED and necessary resistors in a single PCB. As an Amazon Associate we earn from qualifying purchases.

is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to products on. Using a Potentiometer as an Analog Input.Step 2 – Connecting the Three Potentiometers.Controlling the LED Brightness with PWM.Common Cathode and Common Anode RGB LEDs.

Arduino rgb led sunrise sunset