PAGE 052 OF 150 · WIRING LEDS
Matching LEDs in a String
Same colour and batch behave most alike.
LED SYMBOLTriangle points from anode to cathode; the arrows show light leaving the part.
Why matching matters
In a series string all LEDs share one current, so brightness is similar if they are the same type. Different types may have different maximum currents, and the lowest limit applies.
Good practice
- Use the same part number, ideally from one batch.
- Pick current from the weakest LED's rating.
- Keep them at similar temperature.
- Do not mix a small indicator with a power LED in one string.
Mixed colours can share a string if their current ratings match, and then the resistor accounts for each Vf.
REMEMBER
In series the same current flows through every LED.Try it yourself
Sketch the circuit on paper first, calculate the values, then build it on a solderless breadboard using a low-voltage supply. Measure with a multimeter before you make anything permanent.
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