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Resistors on each led? Answered

 I am designing a led array consisting of 17 leds in parallel using 4.5 volt power supply.The led calculator is telling me to use 62 ohm resistor on each - leg of the LEDscould I just use one 62 ohm resistor right after the power supply? Or maybe like 1 or 2 100 ohm resistors?

I'm using blue leds
3.3 max voltage
20 Ma


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Re-design

Best Answer 9 years ago

There should be no problem using one resistor.  Just use a resistor big enough to handle the load or it will overheat and burn out, but your leds should be fine.

I don't know why almost all of the diagrams show a resistor for each led except if you're mixing colors of shapes and they take different voltages you can account for that by using a diff. value resistor for each type led.

And should I happen to be wrong on this (but I'm pretty sure I'm not) someone will correct me.  Sometimes it's easier to get a correction than an answer.

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Re-designRe-design

Answer 9 years ago

You'll have to recalculate the value of the resistor.

Tell me what you get as the value and I'll tell you if I got the same value.

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the_burrito_masterRe-design

Answer 9 years ago

Thanks, I decided to just use 100 ohm resistors in front of each led , they didn't need to be too bright for this project. I'm happy with the result.

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Re-designthe_burrito_master

Answer 9 years ago

All that matters in the end is that it works and you're happy with the result.

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iabler124

9 years ago

Try a bread board and use a 225 ohm resistor. That should work. If it doesn't, use that 62 ohm resistor on it but only at our own risk. You might blow your LEDs.