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Why do you connect resistors separately to three terminals of an RGB LED?
If red and blue leds are turned on, this means a load of a value. If green and blue are lit, this means a load of another value, and so on. You cannot match all possible states with a single resistor, so you place three on the other side, allowing each resistor to deal with a single led.
How many terminals are there in RGB?
four terminals
The working of RGB LED is, it has four terminals, in which three colors red, green, blue, and one more terminal represent anode or cathode depending on its type.
What happens when we use one resistor on an RGB LED?
Now, let’s discuss what happens when we use a single resistor on an RGB LED. We can assume that our power source is 5V, then the typical forward voltage of the red LED is 2V, while the green and the blue LEDs would be around 4V. As indicated in the diagram, the LEDs are obviously connected in parallel, a crucial aspect to this problem.
How many resistors should I use for red and blue?
You should use 3 different resistors, one for each color, although the blue and green have the same specs. At 150mA the forward voltage for the red is 2.2v, green is 3.5v and blue is 3.5v. So you should use a 22ohm 1watt resistor for the red, and 10ohm .5watt resistor for the green and blue.
Can a single resistor be used with multiple LEDs?
While not the overriding problem with RGB LEDs, your single resistor has another issue. When you have a single resistor and a single LED, you can calculate the maximum current that will go through that resistor. But with a single resistor and multiple LEDs, that resistor now needs to channel the current that flows through ALL of the LEDs.
Why can’t I share resistor on the common anode or?
And that is why you cannot share a resistor on a common anode or common cathode RGB LED or even on an LED array. So you really need to have one specific resistor for each of the LEDs in an RGB LED or LED array.