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Carbon
04-23-2008, 09:34 PM
I tried searching for this but couldnt find anything so Im putting this out here for the experts.

I have some LED's that are rated to 3.7 max volts but I want to run them off of 12 volts. Will this burn them out? What can I do to run them at these volts? Or do I just need to get 12 volt LED's?

Any help is appreciated.
-Thanks
MTL-TSX
04-24-2008, 01:08 PM
It would depend on exactly what type of led you have. But yes connecting these directly to 12v would burn them.

The leds on eBay that are "12v" are merely regular leds with Resistors already attached for use with 12v. So you would need to buy some resistors and put those in series with the LED. You would also need to find out the current requirements of the LED.

Hope that helps.
zhieson
04-24-2008, 01:12 PM
IMO, sounds easier and cheaper if you just buy new 12v ones. There are sites (and ebay) that sell them pretty dirt cheap.
MTL-TSX
04-24-2008, 01:16 PM
Yeah it probably is, but if the LEDS he has are much brighter than whats on eBay or if he got them really cheap then getting the resistors would probably be cheaper.

Resistors are like 5-10cents each, and connecting them to the LED wouldnt be hard if he is willing to solder them. If not he could just "braid" the ends together tape it up and hes good to go.
Carbon
04-25-2008, 12:50 AM
Yeah it probably is, but if the LEDS he has are much brighter than whats on eBay or if he got them really cheap then getting the resistors would probably be cheaper.

Resistors are like 5-10cents each, and connecting them to the LED wouldnt be hard if he is willing to solder them. If not he could just "braid" the ends together tape it up and hes good to go.

Yeah the LED's I have are really bright and were prety cheap. So Iwant to try and run these. How many resitors do I need? the max voltage per LED is 3.6V not 3.7V and I will be running 2 in a series off of 12 volts.
Carbon
05-01-2008, 02:25 AM
Still looking for help.
MTL-TSX
05-01-2008, 03:36 PM
Hi, if you can find out the current rating on the LEDS i can help you out.

Also are these going to be mostly on whent he car is running? If so the circuit will need to be designed for 14.4v. (best to be safe)
Carbon
05-05-2008, 05:43 AM
where do I find the rating?
luder917
07-16-2008, 08:47 PM
kinda late but if youre going off 14.4 volts, you could just run 4 of those LEDs (3.6V each) in series with no resistors needed.
Carbon
07-17-2008, 01:29 AM
kinda late but if youre going off 14.4 volts, you could just run 4 of those LEDs (3.6V each) in series with no resistors needed.

Thanks but I already figured it out wired it and installed it.