# COMMUNITY : FORUMS : TECH

## 2 Different LEDs on One Circuit?

If I have a Red Led that takes 2v and a green led that takes 3.2 volts...then can i use 5.2 volts to power them?? Will that work without giving too much juice to the Red LED?? THANKS!

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Joe426 (author) 10 years ago
SOMEONE HELP PLEASE!?!?! OR SHOW ME A DIAGRAM?? THANKS!!!
10 years ago
Why, do you not like the help you have been given? Pat. Pending
Joe426 (author)  Patrick Pending10 years ago
I just didn't understand it fully. if i wire it like this - will it work? THANKS!
Joe426 (author)  Joe42610 years ago
or would i need another resistor between the power and 3v led?
10 years ago
Yes another resistor between power and the 3V LED would be better. You need to calculate the appropriate values for each of these resistors. By including a series resistor it helps protect the LED from excess current flowing due to variations in the power source.

Resitance = V(source)-V(LED) / I(LED)

Do you know the forward current for each of the LEDs?

Pat. Pending
Joe426 (author)  Patrick Pending10 years ago
one is 3.5 volts, the other is 2 volts. I tried wiring them in a series with resistors - they haven't burned out and seem to be as bright as ever.
10 years ago
I'm not sure if you misread my question, as you have given me the forward voltage drop of the LEDs instead of the forward current. How have you calculated the value of resistor required? Pat. Pending
Joe426 (author)  Patrick Pending10 years ago
using the metku mod calculator - i just added 3.5 volts +2 volts = 5 volts. then i said the power source was 9 volts and then calculated a resistor value. so - I said i had one 5.5v led in a circuit powered by 9 volts...and it spit out a resistance.
10 years ago
It looks like you used 20mA suggested by the calculator for the forward current. So it looks like we have come full circle back to my original post, where I said it would work fine as long as they have the same current requirement. Cheers, Pat. Pending
Joe426 (author)  Patrick Pending10 years ago
thx for the paitence and help!
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