2000lumen+ LED reverse lights.. *Output Pics* MMMmm...

[VanIsleDSM]

Yes you read correctly.. I'm that ridiculous.

I've been working on my full custom LED tail light retro for quite some time now.. I'll post up the other stuff soon too.. all micro controlled with PWM dimming for marker/brake functions and 8 channel sequential turn signals with adjustable fade in and fade out...

The reverse lights will be PWM dimmed for parallel parking and such around town.. but if I'm backing down a dark driveway.. well.. it won't be dark!

I can also strobe these babies for fun.. or for those pesky tail-gaters... heheh.



I used 100mA 5chip superflux style LEDs.

Over 100 degree radiation.. so it's just a huge flood.. these guys have no problem lighting up my whole back yard.

So I ran out of the solder i had.. it was lead solder.. worked great.. I ran out to canadian tire and bought some bernz-o-matic lead free electircal solder.. all they had.. I did the board pictured in the back with this new stuff.. man.. what a waste of money that was. Such a huge pain to solder up that second board.. the lead free solder takes so much more heat to melt.. more than I liked to use on the LEDs.. and then it doesn't flow very well either.. and solidifies so quickly.. but then somehow stays very hot.... the properties of lead solder seem much more desirable to me.. I won't buy this crap again.. although it may just be junk solder.. maybe you can get good lead free solder.. but I won't be chancing it again.. I'm going to buy a nice spool of lead and screw this stuff....

I fit 38 LEDs per side... at a conservative 75lm/w I get 1000lumen per side..(3.5Vf x 100mA x 38 = 13.3w per side) pretty bad *** seeing how 1 50w halogen headlight is about 1000lumen.. from the bulb.. not taking into account all the optical loss of reflection and refraction.. something the LEDs don't have to deal with... so until I get around to doing an OEM HID retro.. my LED reverse lights will be brighter than my headlights

Kinda pointing a little towards the ground, but it was hard to position them properly.. and it was raining a bit so I didn't want to screw around forever.. you get the point though... they're F'n BRIGHT!

Without further ado...

 

[TorchBoy]

Mmm, that's quite nice. Where did you get the LEDs from and how much for the whole thing?

 

[VanIsleDSM]

Ebay, there are a few sellers from HK.

Just search for "100mA white LED"

I got a bag of 100 pieces, more than 2500lumen for $60 shipped... I think that's gotta be the best deal going for LED? no heatsink or special driver needed.

I'm sure they're the same as the Best Hong Kong LEDs.. they look exactly the same.. there are lots of info about them on HIDplanet, lots of people have ordered them now and are quite fond of them.. I think I'm gonna get some warm whites for the home.. I hear they are kind of yellowish, but that was only 1 report, no pic.. maybe mix in a few regular whites too if that's the case... and i just noticed now you can get a 40 degree version in a 5mm package.. too bad.. I would have liked to have used some of those along with the 100degree'ers to add some distance.. they weren't available when I ordered mine...

As for longevity one member reports having used them as DRLs for 16,000miles @90mA with no ill effects.

 

[frenzee]

Good job. I need to do something along those lines.

 

[TorchBoy]

I got a bag of 100 pieces, more than 2500lumen for $60 shipped... I think that's gotta be the best deal going for LED?

I wonder... 14 Cree P4s from DX, add $1.70 bulkrate = $59.82. 176 lumens each at 1 amp = 2464 lumens.

Yes. :laughing:

What's the idea with the brake/indicator functions you mentioned? These aren't just reversing lights, but they are just white.

 

[VanIsleDSM]

These are just reverse lights..

But I am getting rid of all the incandescents in my tail lights.. I already have boards made for the marker/brake function and turn signals.. just finishing up some work on the tail lights themselves.. and I still need to design and etch the PCB for the controller.. and work out one last little bug in the coding.

Thing is with the P4s is you also need heatsinks and drivers.. and you'd need a damn big heatsink to run 5-6 in the space of my reverse lights.. there would be a lot of heat...

 

[TorchBoy]

You're talking about the same order of magnitude for the efficiency, so there'll be very roughly the same amount of heat produced (probably a little more since they don't manage 75 lm/W at 1 A) - the P4s just make it from a smaller package. You'd have to mount the stars on something, so might just as well use it to help conduct the heat away, and a resistor is just fine for a series of three.

Don't get me wrong, I really like what you've done, and it looks more impressive. I presume the off-square look is to fit with your vehicle styling? Why only two LEDs per series?

 

[VanIsleDSM]

Hmm.. I suppose there is just as much heat.. I think they must be much more efficient.. there doesn't seem to be very much heat at all.. obviously easier to evacuate it over much more surface.. I'll do some temperature testing soon..

2 per string because I used 9v regulators.

I think with high power LEDs you should be using a constant current device.

 

[mds82]

That is very cool. Do the new assemblies actually fit inside the original tail light housings?

 

[VanIsleDSM]

Yeah they all fit right in.. the brake and signal boards bend around a corner as they fit in as well... I'll post pics of the whole thing soon... just a pain in the *** to have to make them 800pixels.. I don't get it.. who has a 15" monitor still? what's the point?

 

[mds82]

Get the windows XP image resizer from the Windowx XP Power Tools

http://www.microsoft.com/windowsxp/downloads/powertoys/xppowertoys.mspx


its real easy!

 

[TorchBoy]

2 per string because I used 9v regulators.

I think with high power LEDs you should be using a constant current device.

Seems like doubling up - a series resistor does control the current, just not exactly. How about some more photos of high and low modes?

just a pain in the *** to have to make them 800pixels.. I don't get it.. who has a 15" monitor still? what's the point?

"Ours is not to wonder why, but to..." etc. Seriously, I think the decision may have been to do with preventing too much horizontal scrolling for text, not necessarily because of the pics themselves.

 

[-Virgil-]

Sweet! What kind of vehicle are you putting these in?

 

[Diesel_Bomber]

That's neat! Much better than drop in LED replacements.

I think the 800 pixels is due to bandwidth. Many of us are still on dial up; highspeed isn't available out in the sticks. Those pictures took me 5 minutes each to download.

Making a WAG from the OP's username, I would guess the vehicle is a Plymouth Laser/Mitsubishi Eclipse/Eagle Talon.

:buddies:

 

[Illum]

100ma LEDs....
SMT....
thats alot of heat by itself :sweat: no heatsink?

 

[VanIsleDSM]

Yep.. '97 Talon Turbo AWD.

They aren't SMT, through hole mounted... each LED has a nice thick metal base on the cathode.. I'm going to do some long term temperature testing with a thermocouple here pretty quick.. but so far there is no heat problem at all.. the LEDs barely get warm to the touch after 5 min or so.. The resistors on the back get hotter than the LEDs..

If you think about it.. there's just so much more surface area for the heat to be pulled away from with this many dies.. each LED is 5 20mA chips.. so there are 190 LED chips on each side.. It's a lot easier to suck heat out dissipate it from all that surface area.. compared to 5 CREE or whatever..

I don't really know efficiency numbers for small 20mA chips.. I imagine they are more efficient generally though.. than the power chips? Maybe I'm getting a lot more than 75lm/w, and maybe that's why there's barely any heat..

Either way.. if there did end up being too much I'd just slather some nasa thermal epoxy I have on the back of the board and slap a heat sink on there to suck all the heat out of the resistors and the LEDs.. but I really don't think I'll need to do that.

 

[TorchBoy]

Maybe I'm getting a lot more than 75lm/w, and maybe that's why there's barely any heat.

That'll still be producing almost 90% heat, and only about 10% light. A quick calculation gave 11 or 12 watts of heat dissipated by each array. Have you measured the actual current they're running on?

 

[VanIsleDSM]

I've derated the LEDs to 90mA while cold.. they start off drawing 1.56amp per side and after a few minutes of warm up they seem to reach stable thermal state quite quickly and top out at 1.85amp which is just over 97mA per LED. I'm sure they'll go a bit higher if left on for an extended time.

 

[Changchung]

:twothumbs:rock:

 

[LukeA]

That'll still be producing almost 90% heat, and only about 10% light. A quick calculation gave 11 or 12 watts of heat dissipated by each array. Have you measured the actual current they're running on?

Um, wouldn't 75lm/W be around 31% efficient for white light?