Any led's that can run direct drive at 3V?

[carnal]

Any led\'s that can run direct drive at 3V?

I've been amazed at how some non luxeon LED's can run direct drive at 3V in a bi-pin socket flashlight just by stabbing the led in a mag's bi-pin socket (like a AA or AAA Mag) I've got lambdas MJLed's, but otherwise is this concept a huge secret or generally unknown? Or are there no leds around that can run that high voltage. Maybe I'm just the hillbilly "that doesn't keep up with current led events"? Or, still yet maybe discreet leds are not bright enough to bother with.

I AM impressed with the MJLeds brightness! And curious.
The BIG question is:
HOW MANY OTHER LED'S CAN RUN DIRECTLY OFF BATTS AT 3V

Seems like I heard of someone talking about a green led that ran direct. COULD YOU ALL SHARE YOUR SECRETS as to WHICH LED's CAN RUN AT 3V or above? And sources if possible.


Thanks in advance

 

[WildRice]

Re: Any led\'s that can run direct drive at 3V?

I have some 3mm greens that runn 28ish mA at 3v, and I have seen somw whites that have a voltage range of 3.0-3.1v.

luck of the draw.

Jeff

 

[carnal]

Re: Any led\'s that can run direct drive at 3V?

Are they bright? How bright compared to the MJLed?

Got any for sale?

 

[ACMarina]

Re: Any led\'s that can run direct drive at 3V?

I've got a handful of 3mms that will run @ 3v. Straight up, drop in with no problems. Don't remember where I got them, though, if you search for when I was trying to find them you'll be able to find them. .

 

[HarryN]

Re: Any led\'s that can run direct drive at 3V?

I have run a Lux III (TWOK) direct drive from 2 x alkaline D cells, which is nominally 3 V. Not full brightness, but they do turn on.

 

[tvodrd]

Re: Any led\'s that can run direct drive at 3V?

[ QUOTE ]
HarryN said:
I have run a Lux III (TWOK) direct drive from 2 x alkaline D cells, which is nominally 3 V. Not full brightness, but they do turn on.

[/ QUOTE ]
I've had H-bin 1W LS's pull near 250mA from a fresh 123, and the run time is insane!

Larry

 

[Chop]

Re: Any led\'s that can run direct drive at 3V?

Lots of LEDs can be DD'd on 3V. I do it all of the time. It's just a matter of how bright you need it to be.

I made a few Lux III lights using J Vf luxeons to make a few "menu reading" lights without reflectors for some of my more aged friends. They were all direct drive.

 

[HunterSon]

Re: Any led\'s that can run direct drive at 3V?

I just built an E1e "SuperFlood" using a direct drive TWOH Lux III. I moved the led right up next to the glass lens for a super wide flood. Very bright for a Luxeon driven at 3v.

 

[IsaacHayes]

Re: Any led\'s that can run direct drive at 3V?

a luxIII TxxH would make a great DD light, it would only run probably at 1W levels, but it might pull at least 350ma!

I know a "J" Vf LuxIII is about equivalent to a "H" Vf LuxI. So an "H" LuxIII would be awesome.

HunterSun, what ma does it pull on 3v?

 

[Turbo_E]

Re: Any led\'s that can run direct drive at 3V?

i just modded my ebay 6 led light (3V) I put in 6 X 20,000 MCD LEDs. boy its bright! I also took the LED out of my Innova Keychain light and replaced it with a 20,000 MCD LEd. again, painful to look at directly.

I'd say its 2X brighter. I can't find any specs on the Innova LED. I cant believe i spent $20 on it /ubbthreads/images/graemlins/frown.gif

I got my 20,000 MCD LED off eBay for $5/10. free ship.

 

[asdalton]

Re: Any led\'s that can run direct drive at 3V?

White LEDs use a blue emitter plus a phosphor. The theoretical minimum for generating the blue light is around 2.8 V. Above that point, the current increases approximately exponentially with voltage. How well a particular LED runs at 3 volts will vary from piece to piece.

If you want to direct drive at 3 volts, lithium batteries are best since they start out a bit higher than 3 volts and their voltage stays much flatter during discharge than alkaline cells. That's how the original CMG Reactor worked.