LED Question

A

adphill

Member

• Aug 16, 2018

• #1

I am new to lighting models, and I am a little confused about the volts/amps distinction. Can any 12V power source be used for a 12V LED, or do I also need to consider the amps? If so, what is a typically appropriate amp rating for a LED power source?

Thanks, I appreciate it.

 

freezerbee

New Member

• Aug 16, 2018

• #2

Depending on how many LEDs you're trying to drive and how much power you have, you'll need to do a bit of math to figure out how much resistance your circuit needs. The diode will try to dissipate as much power as you put into it and 12V will fry that poor little guy.

I recommend: https://sciencing.com/wire-leds-12v-5743679.html
Or for a slightly more comprehensive primer, check out https://learn.sparkfun.com/tutorials/light-emitting-diodes-leds

 

xl97

Master Member

• Aug 16, 2018

• #3

most small/accent leds need (roughly) 1.7-2.1v for reds and a few other colors.. rest of the colors usually take anywhere from 3-3.3v..

if your leds are configured in a way that they can take up to 12v.. then you should havent any issues.

If your battery source if higher than the leds forward voltage.. you will need some resistors to ensure only 20mA or so of current gets to the led.

 

3Dsf

Sr Member

RPF PREMIUM MEMBER

• Aug 16, 2018

• #4

Okay - I posted a link to this set of articles recently. But the section on LEDs might be of interest to you:

https://sites.google.com/site/millenniumfalconnotes/lighting-models/leds

 

A

adphill

Member

• Aug 16, 2018

• #5

Thank you everyone, this is extremely helpful. I appreciate it.

 

Great_Bizarro

Sr Member

• Aug 16, 2018

• #6

http://www.ohmslawcalculator.com/led-resistor-calculator You can run them at higher voltages than listed but eventually the magic smoke comes out and they dont work then.
Here is an easier one http://led.linear1.org/1led.wiz for a single led
& http://led.linear1.org/led.wiz for an array

 

Last edited: Aug 16, 2018