# pictorial review of LEDs



## Illum (Feb 6, 2008)

*pictorial review of LEDs [lotoPics Warning]*

Modified from a previous thread concept due to lack of physical differences between CREE editions. Now its a somewhat ideal platform for visual references. :thumbsup:

scratched LuxIII star


 

 



LuxV in my L4


 



 

 



USWOL SSC emitter


 



7060 XR-E in my P1-CE


 



7090 Q4 in My L0D-CE


 



If  has different versions of LEDs could you post a pic? :thanks:


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## VidPro (Feb 7, 2008)

*Re: pictorial review of LED generations?*

here is some weird ones, just to keep your thread going.






that 20w thing 






that seoul AC thing


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## Illum (Feb 7, 2008)

*OSRAM versus Luxeon 5*

Seoul AC?
you actually managed to acquire one? kool

might as well add some more myself
source: https://www.candlepowerforums.com/threads/115286
OSRAM OSTAR LE W E3B, 6 die..its a beauty




the OSRAM compared to a LuxV [source: www.tauchfunzel.de/]




OSRAM OSTAR 4die [source:www.pro-light.jp]




Comparison between Ostars




OSRAM products: Ostar listing
http://catalog.osram-os.com/catalogue/catalogue.do?favOid=000000010001fefb00550023&act=showBookmark


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## Fallingwater (Feb 7, 2008)

*Re: pictorial review of LED generations*

http://home.comcast.net/~trivalvid/20W-4.JPG

Why would anyone want to put dies in that weird position? Why not a square or a rectangle?
This looks more like something out of a 1980 videogame.


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## Illum (Feb 7, 2008)

*Re: pictorial review of LED generations*



Fallingwater said:


> http://home.comcast.net/~trivalvid/20W-4.JPG
> 
> Why would anyone want to put dies in that weird position? Why not a square or a rectangle?
> This looks more like something out of a 1980 videogame.



I'm inclined to think its drawing low current to light the dies up but apparently the individual dies operate at slightly different currents

With the help of a magnifying glass...I can finally count all the bondwires in one sweep





trial 2




TWENTY-NINE bond wires compared to SEVENTEEN for the P7 
Wonder why the P7 needed that big of a LED to fit 4 when it can easily fit like 16 if its fabricated like the MC-E:shrug:


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## TigerhawkT3 (Feb 8, 2008)

*Re: pictorial review of LED generations*

Awesome thread. I'm adding it to the Welcome Mat.

SSC USW0I:




XR-E Q2:




XR-E Q5:


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## Illum (Feb 8, 2008)

*Re: pictorial review of LED generations*

:thanks: TigerHawkT3

the SSC is a weird LED IMO...there are NO STRAIGHT EDGES under the dome...compared to luxeon/CREEs they have ABSOLUTELY NO SYMMETRY when you look at it from an angle, but the output is certainly very impressive for its size

a couple more 
UFO Starfish LED, [rehosted from thread made by user Brlux][05212009 rehosted again]


 



 



OSRAM Golden Dragon [I took apart my sylvania 4AA lantern, here posted post 122]




OSRAM Platium Dragon LED




Philips Rebel [more pics and info available at *100 Lumen Rebel technical evaluation*, Rebel NVND]


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## VidPro (Feb 8, 2008)

*Re: pictorial review of LED generations*



Illum_the_nation said:


> I'm inclined to think its drawing low current to light the dies up but apparently the individual dies operate at slightly different currents



that is correct, it is being driven to just where parts of it light up, and its a bit sloppy in gate precision.


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## yo6ial (Feb 3, 2009)

Here's one, perhaps less seen or common Cree led... 
of witch i could only guess the bin. It's a 6000+ kelvin tint, and at around 700mA pushes close to a SSC U-bin P4 driven at the same current.
So it could be a Q5. Too close for my eyes to make a big difference, I'd say that the Cree seems to just a (tiny) bit dimmer. 




By yo6ial at 2009-02-03

And.. i know, it's a bit offset. It's annoying me too. :ironic:

And a Chinese (One Watt'er ) 




By yo6ial, 2009-02-03
As bright as ...
Not to mention that it gets hot too :laughing:.


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## PCC (Feb 3, 2009)

Here are a few pictures that I posted in another thread. I could have sworn that I had found a similar thread to this but now I can't find it anywhere.

SSC P4 (supposed to be U-bin)





SSC P7 (not sure about the bin)





Luxeon III (I think)





Cree XR-E (unknown bin - thinking it's Q5)


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## was.lost.but.now.found (Feb 3, 2009)

PCC said:


> Here are a few pictures that I posted in another thread. I could have sworn that I had found a similar thread to this but now I can't find it anywhere.


 
Nice macro shots. It that the phosphor you can actually see on the P4!!??


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## brightarc (Feb 3, 2009)

Cree MC-E WC K bin


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## PCC (Feb 3, 2009)

Yes, I believe so.


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## bshanahan14rulz (May 6, 2009)

PCC said:


> Cree XR-E (unknown bin - thinking it's Q5)



It's at least a warmer tint. Strange how the die is crooked and phosphor layer has ragged edges. Better than SSC's strategy of just piling a glob of phosphor on top of the chip and encapsulating the whole kaboodle...

Neat pics, wish this thread were more alive.


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## Illum (May 6, 2009)

*CREE comparisons NW+WW+W100 et al.*

heh, glad to see this thread came back to life...



bshanahan14rulz said:


> It's at least a warmer tint. Strange how the die is crooked and phosphor layer has ragged edges. Better than SSC's strategy of just piling a glob of phosphor on top of the chip and encapsulating the whole kaboodle...
> 
> Neat pics, wish this thread were more alive.



Interesting...I've never seen a LED with a die _that_ crooked before. As for the Jagged edges, thats an optical illusion looking through the jelly dome. Rather than being completely transparent, its something else altogether. Its usually not noticeable if theres low contrast between the upper phosphor coat and the lower but in this case it illustrates it very well. 

More LuxVs...




_Nichia CS




 _ Neutral White


 



Warm White


 

 



W100 "Q4" [lol, a complete lack of phosphor IMO]


 

 

 



Luxeon I Lambertian [Red]


 

 



the M-bin MC-E that now resides in my L4


 



Edison RGB 3 Watt Fullcolor EP3M-4S00


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## rizky_p (May 7, 2009)

nice posting, those some old leds bring back memories. oh the tears and sweat


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## Illum (May 8, 2009)

rizky_p said:


> oh the tears and sweat




of frantically ripping them out then trying to revive them after your mods are done? yeah...

Cyan Side Emitter




Lumina Ceramic 




SSC P9


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## seaside (May 8, 2009)

Good pictures. Thanks for uploading.

This could be a silly question, but also could be an important one... so... let me ask it.

Can anybody tell what's the visible difference between P4,Q2,Q3,Q4,Q2 and R2?

I hate when manufacturer made everything looks the same for whole lot of different stuffs.


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## Th232 (May 9, 2009)

Physically, I believe they're identical. Only way to find out the difference is to measure the amount of light coming out. The different flux bins are due to variation in manufacturing, just the random things that can't be eliminated regardless of how hard you try, so they make them then test them to decide which bin they fall into.


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## Coolricks (May 9, 2009)

AWSOME!!!, where do you guys buy or get that kind of LED's?


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## Illum (May 10, 2009)

*Three wires versus four*



seaside said:


> Can anybody tell what's the visible difference between P4,Q2,Q3,Q4,Q2 and R2?



there are no stupid question here 
N2, N4, P4, Q2, Q3, Q4, Q5, R2, possibly R4 are all representation of flux within the CREE XR-E series, so essentially they are treated the as the same type of LEDs off the forum. Not sure if you were with us back in 2006, when Lumiled luxeons were distinguished between voltage "bins" and tint "bins." CREE N4, P4, possibly Q2 earlier versions you should be able to find only three gold bond wires underneath the jelly dome, the later versions, a fourth bond wire was used to increase the amount of current the LED can receive, plus an increase in the "plateau" under the LED die space.




heres a CREE XR-E "P4" I used for another project, notice theres only one bond wire coming from the positive end?

to increase the amount of power CREE added a second bond wire, with the addition of a bigger die platform. 
XR-E Q5 from Zebralite H50




unfortunately after the Q4, every succeeding flux have 4 bond wires, I have looked on the surface of the LEDs, on the base, back of the case, etc...no dice. Unlike Luxeons... CREEs does not have the habit of printing their bin numbers somewhere on their star



Coolricks said:


> AWSOME!!!, where do you guys buy or get that kind of LED's?


that depends on that your looking for...  
theres no "all-in-one" place to find all LEDs as they are often designed for vastly different applications. If you can point out which LED that interests you I might be able to retrieve a couple links regarding where you may purchase them from


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## v188 (May 10, 2009)

To a newbie, this is a great pictorial resource. thanks for the photos!


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## Illum (May 21, 2009)

*XR-E versus XR-C*

hosting pictures of the XR-C LED in my new Life Gear 1AA with comparison to previously hosted XR-E W0100 "Q4"

XP-C




XR-E




I hope this will finally relieve issues between the differences in the two types. The XR-C has a significantly smaller die surface, which makes it easier for collimation...but a decreased output relative to the XR-E under the same driving specifications.


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## Illum (May 24, 2009)

*The CREE Ring*

I just noticed that the silver ring on CREEs have the top rounded but the bottom chamfered instead of sitting squarely on the substrateoo:


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## wquiles (May 24, 2009)

Illum said:


> I just noticed that the silver ring on CREEs have the top rounded but the bottom chamfered instead of sitting squarely on the substrateoo:
> 
> (snip pics)
> 
> ...


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## Illum (May 24, 2009)

:thanks:

I've been wondering if I can remove the ring with*out* damage so while looking for a place to pry from I noticed that the bottom half of the ring seems offset a bit...and the camera did a very good job telling what I need to know...now I just need some guts to actually pry one:candle:

I wonder why theres toothmarks on my CREE substrates...I have yet to look at other CREEs.


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## Mr Happy (May 24, 2009)

Illum said:


> I've been wondering if I can remove the ring *with damage*...


In that case, just hack away! :thumbsup:


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## Illum (May 24, 2009)

*Lateral proportion of LEDs XRE-Luxeon-MCE*

LuxDrive CREE XR-E 


 



Lumiled Luxeon [excuse the fuzz]


 



[Cutter?] MC-E mounted on a 8 Pin star [individually addressable dies]


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## Illum (Jun 1, 2009)

*Miscellaneous pics...*

weird LEDs... [rehosted from thread made by user frenzee]
[URL=http://img221.imageshack.us/my.php?image=dsc00973wb7xa5.jpg]

[/URL]




River Rock 2AAA LED, 3 die [rehosted from thread made by user Kyrosphinx]





Lumiled Superflux [4 pin]


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## Illum (Jun 1, 2009)

*MCE Trails*

_*Mods, sorry for so many posts...been meaning to do some organization by categorizing specific elements under different titles for easier referencing.*_​
There is a "black square" where the positive pin literally connects to the negative pin. I think it might actually be a diode for reverse current protection but I'm not sure. 

Short dash = "diode" bondwire
long dash = solid [not bind wire] connection
Solid = bond wire connection

MC-E 




MC-E Highlighted


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## bshanahan14rulz (Jun 2, 2009)

esd protection diodes, eh?

that cyan luxV side emitter looked cool!


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## Illum (Jun 2, 2009)

yep...

I just looked at the MCE datasheet and lo...




they were diodes. =P

Yeah, the cyan side emitter is an interesting one...not mine though, dunno where that pic originated.

Side emitters actually use a glass optic rather than the conventional jelly, so they are actually the hardest to break but they do chip easily


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## baldux (Jun 2, 2009)

Awesome thread and great pics. :thumbsup:
So many different LEDs out there, quite overkill for a noob like me.
Thanks for sharing.


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## 4sevens (Jun 4, 2009)

We JUST got these in... We'll be testing these mystery LED's for deployment of a killer 4sevens light before year end


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## Illum (Jun 4, 2009)

eek!
I thought we were still on factory lead time?




baldux said:


> Awesome thread and great pics. :thumbsup:
> So many different LEDs out there, quite overkill for a noob like me.
> Thanks for sharing.



Because of the overkill came the concept of making this thread as reference...to the micro cosmos people normally don't give a second thought about


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## marschw (Jun 6, 2009)

4sevens said:


> We JUST got these in... We'll be testing these mystery LED's for deployment of a killer 4sevens light before year end


Those look a lot like XP-Es, but with a slightly different substrate... maybe SSC's version of them?


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## SilentK (Jun 6, 2009)

looks like an awfull amount of bondwires for a single die led.


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## Illum (Jun 6, 2009)

its not a CREE, and its nowhere near single die..

its more like 10 dies in series then several strings paralleled across to form a square

see: http://www.luminus.com/content1504


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## SilentK (Jun 6, 2009)

Illum said:


> its not a CREE, and its nowhere near single die..
> 
> its more like 10 dies in series then several strings paralleled across to form a square
> 
> see: http://www.luminus.com/content1504



:wow:


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## spearsniper (Jun 7, 2009)

4sevens said:


> We JUST got these in... We'll be testing these mystery LED's for deployment of a killer 4sevens light before year end


 
Not really a mystery LED. These are the long awaited PhlatLight SST-90's.
Don't suppose you have any surplus stock you would like to part with :twothumbs


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## SilentK (Jun 7, 2009)

"The light emitting surface of the SST-90 is a single, monolithic die that is nine square millimeters in size. The SST-90 produces 1,000 lumens with 10 watts input (at 6,500K) and 2,250 lumens at its maximum rated drive current. PhlatLight LEDs are mercury-free and highly reliable and have a lifetime of 60,000 hours with lumen maintenance of greater than 70 percent. The SST-90 is ideally suited for general lighting applications, including architectural, retail and residential lighting as well as wide area street and parking lot lighting."


:huh: wow. i will not eat next month. all my food money will go into this light when i comes out. :nana:


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## Illum (Jun 7, 2009)

spearsniper said:


> Don't suppose you have any surplus stock you would like to part with :twothumbs



thats what I'm wonderin
And since your moving on to SS*T*s, any surplus stock on MCE's?


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## mattchatwin (Sep 4, 2009)

*Re: Miscellaneous pics...*

Hey Illum, what were you testing with the Superflux and the copper heatsink you added? How did it go? Reason I ask is because I've been scouring the web looking for help. I have been experimenting with LEDs (total noob) and have designed a LED strip to mimic the Audi LED Day Time Running Lights on my Honda Accord. The problem is some of them keep burning out. I have 15 in each headlight in 5 sets of 3 in series with a resister and I built a 12v regulator. I am using 4 chip superflux from oznium, rated at 80mA and 3.5 v, I'm thinking I should regulate them at say 3.3v and 70mA to reduce the heat a little and put some copper on the anodes to act as a heatsink....what do you think?





Illum said:


> weird LEDs... [rehosted from thread made by user frenzee]
> [URL="http://img221.imageshack.us/my.php?image=dsc00973wb7xa5.jpg"][/URL]
> 
> 
> ...


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## Illum (Sep 4, 2009)

you know, that wasn't _my _pic, its there as an illustrative reference

I used the pic because it gave a reasonable comparison of the superflux's footprint with the familiar 1/4 watt resistor.

As to the intent of the testing I have no idea what it was about.


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## VidPro (Sep 4, 2009)

those things handle the heat much better than the standard 5mm type of leds, but 80ma is still a bit high for them.
i use them more like 5mm leds and drove them more at 40ma instead. meaning replace the SAME app at the same currents that would run a 5mm hard, with those running soft.

syncing the hot leg (one leg gets much hotter than the other) with cute stuff works out good. i used a folded heat sync design which acted also as a bar connector for one side of quad dies overdriven, and they are still running today, the bigest problem was still the small spaces with little air movements.

the "math" for automotive leds is more around 14.5v not 12v , so using a few less leds per string and putting in more resistance to get to the votlage, then setting the Calculated current at the 14.5 and just having more dim when running solely off of battery. by having more resistance, you have a better buffer of the voltages as it changes around.

[@] - [@] - [@] <--- pirahna leds
| . | -| . | -| . | <--- Led legs
/- -\ / - -\ / - -\ <--- folded sync making the connections, much longer, you get the idea.

- . <--- extra charachters added to space it mean nothing. 

at any rate, you need so many of any small leds, its really better to shove in some "high powered" leds and get the job done in less moves, they can also take more fluxuations without failing, and have better ways to sync.
Plus any sync hanging off legs of leds, means the possibility of SHORTING, nothing can touch nothing, and now i got huge conduction plates ready to ground out on something.


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## mattchatwin (Sep 4, 2009)

Thanks guys for the input, here's a pic of what I have so far, in person they are quite a bit brighter and this was taken when I had only 11 LED's per lamp but was running into problems. Rebuilt with a 12v regulator and 15 LED's in 5 sets of 3 in series and now need to cut the voltage down some more so will try some of the ideas you guys gave me. Thanks!!


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## VidPro (Sep 4, 2009)

well really nice car, but WHERE are the leds  like turn on the lights or something


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## mattchatwin (Sep 4, 2009)

Ha ha, okay okay, here are a couple new ones (before the driver side burnout):
















As you can see from an angle, it definately sticks out more and that's because I'm not smart enough to make a mount that keeps all the LED's pointed forward like a real Audi...that will be on test build number 47 :sick2:

Guys (gals?) I'm totally open to suggestions and if I need to continue this post somewhere else just let me know....thanks for all the help.



VidPro said:


> well really nice car, but WHERE are the leds  like turn on the lights or something


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## mattchatwin (Sep 4, 2009)

Oh, and spec's for those LED's can be found here:

http://www.oznium.com/four-chip-led/questions


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## bshanahan14rulz (Sep 4, 2009)

dont see the "eyelids" on it? I like the subtlety

edit: wow, 2 people replied in the time it took me to type that? I must have forgotten about it in a tab and clicked submit hours later or something


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## OddOne (Sep 4, 2009)

I have a few Optek Optimal XIVs if you'd like pics, but it'd be next week before I can post 'em.


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## Mr Happy (Sep 5, 2009)

*Re: Miscellaneous pics...*



mattchatwin said:


> I have been experimenting with LEDs (total noob) and have designed a LED strip to mimic the Audi LED Day Time Running Lights on my Honda Accord. The problem is some of them keep burning out. I have 15 in each headlight in 5 sets of 3 in series with a resister and I built a 12v regulator.


Do you have a separate resistor for each set of three, or are you paralleling them up?

Problems often happen with LEDs if you wire them in parallel as the current can be unevenly distributed between them. I don't know if this is your problem as you do not give enough information, but it could be. Also bear in mind that the maximum current given for an emitter is usually the absolute maximum under ideal conditions with controlled temperature and good heat sinking. The recommended current for long life in uncontrolled conditions may be half or a quarter of this.


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## mattchatwin (Sep 7, 2009)

*Re: Miscellaneous pics...*

Hey Mr. Happy, each set of 3 has their own resister and I'm thinking you are right. The superflux are rated for 3.5V at 80mA. With 12 volts coming in and 3 LED's that's a recommended 22ohm resister for the 3 so what I was thining is a 33ohm resister so as to get the 80mA, but only 3.2V, what do you think?

Here's another couple pics to show the wiring:














Mr Happy said:


> Do you have a separate resistor for each set of three, or are you paralleling them up?
> 
> Problems often happen with LEDs if you wire them in parallel as the current can be unevenly distributed between them. I don't know if this is your problem as you do not give enough information, but it could be. Also bear in mind that the maximum current given for an emitter is usually the absolute maximum under ideal conditions with controlled temperature and good heat sinking. The recommended current for long life in uncontrolled conditions may be half or a quarter of this.


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## Mr Happy (Sep 7, 2009)

*Re: Miscellaneous pics...*



mattchatwin said:


> The superflux are rated for 3.5V at 80mA. With 12 volts coming in and 3 LED's that's a recommended 22ohm resister for the 3 so what I was thinking is a 33ohm resister so as to get the 80mA, but only 3.2V, what do you think?


There's your problem, right there. With a Vf of 3.5 V and three in series, the total voltage drop is 10.5 V. On a 12 V supply, we have 1.5 V across the 22 ohm resistor giving a current of:

1.5/22 = 0.068 A (68 mA)

Seems good, right?

Only a car electrical system actually operates at about 14 V, not 12 V. So now our calculation is:

(14 - 10.5) / 22 = 3.5 / 22 = 0.159 A (160 mA)

No wonder they keep failing, eh?

What you need to do is put two in series rather than three, and use 14 V, so that your resistor value becomes:

R = (14 - 3.5 x 2) / 0.080 = 91 ohms (5%)

Now if the voltage should drop to 12 V the current will be:

I = (12 - 3.5 x 2) / 91 = 0.055 A (55 mA)

This is still plenty to light up the LEDs brightly.

If you want to be really safe you might try 100 ohms instead of 91 ohms.


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## mattchatwin (Sep 7, 2009)

That was my original problem, but then I rebuilt and I think I mentioned that I am now using a voltage regulator for 12V and I'm getting about 11.91V to the LED setup now, so I should be within spec, other than heat I believe, so will dropping in a higher rated resister cut the heat down to the LED and increase their longevity?


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## Mr Happy (Sep 7, 2009)

mattchatwin said:


> That was my original problem, but then I rebuilt and I think I mentioned that I am now using a voltage regulator for 12V and I'm getting about 11.91V to the LED setup now, so I should be within spec, other than heat I believe, so will dropping in a higher rated resister cut the heat down to the LED and increase their longevity?


Sure, a higher value resistor will reduce the current. Even with the voltage regulator you will still get better control with two LEDs in series rather than three. But if you stick with three, then do try the 33 ohm resistor.


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## mattchatwin (Sep 8, 2009)

I have been using 1W resistors (probably over kill), anything wrong with that?


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## Illum (Sep 8, 2009)

mattchatwin said:


> I have been using 1W resistors (probably over kill), anything wrong with that?



I don't forsee anything wrong with that...
I'm assuming the wattage of resistors is given as the watts [in heat] its designed to dissipate and not the watts [in power] it can conduct.:nana:

V = IR, If R is constant, then voltage will shift in proportion with your current


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## mattchatwin (Sep 8, 2009)

yes, watts in heat it can disipate so I thought the 1W were easier to find and bigger is better.....


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## mattchatwin (Sep 17, 2009)

Well, another failed attempt. Got a couple that are starting to lose their color already and are sure to burn out....are these just crappy LEDs or is it just too hot and restrictive in the headlight housing? Audi's work, why don't mine (okay, bad question).


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## VidPro (Sep 17, 2009)

mattchatwin said:


> Well, another failed attempt. Got a couple that are starting to lose their color already and are sure to burn out....are these just crappy LEDs or is it just too hot and restrictive in the headlight housing? Audi's work, why don't mine (okay, bad question).


 
well provide the exact specs your using, were they nice and bright for the few hours you got out of them ?

measure the exact voltage when the engine is running on your output out of the regulator, and the series and/or parellel arangement, and then measure the resister that your using.

then we can guess  what might be the issue.


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## Mr Happy (Sep 17, 2009)

Most importantly, measure the exact current through the LEDs when the engine is running.


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## VidPro (Sep 17, 2009)

Mr Happy said:


> Most importantly, measure the exact current through the LEDs when the engine is running.


 
he might have already done so, with the usual DMM on ma setting that reading might be so far off, as to be , , , the problem itself.
(because of the added resistance of the meter when in the small Ma position)


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## Mr Happy (Sep 17, 2009)

VidPro said:


> he might have already done so, with the usual DMM on ma setting that reading might be so far off, as to be , , , the problem itself.
> (because of the added resistance of the meter when in the small Ma position)


Yeah, that was dumb of me. In my mind I was thinking to use the 10 A setting, but when you want to measure 50 mA that will not be very helpful.


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## csshih (Sep 17, 2009)

some of my blurry pics.. taken with a point n shoot + lens I found lying around..

guess the LEDs!


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## 4sevens (Sep 17, 2009)

Lumiled's Luxeon V (now Philips)


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## mattchatwin (Sep 17, 2009)

I admittedly never measured the amps becuase of that very reason, I did check the volts and I had a solid 11.89 v off of the regulator under load and while idle, with the 33ohm resister I had about 9 volts to share between 3 leds in series which is well under the 3.5 v spec of the oznium leds. Color was still good, not a crisp white but acceptable (probably around 5500K). Here's the thing though, I've seen heat rating on these max out around 120 degrees F from most companies but i don't know what these are rated at (oznium couldn't tell me other than they will run fine at the temperature they're rated for....duh, that all depends on a lot of variables).....so when I check the heat outside of the headlights just sitting on my workbench they get as hot as 110, pretty close to the threshold i would say, and with the quantity (15) tight up against the glass they probably don't get much circulation so heat would be an issue unless I get a really aggressive heatsink on them somehow and vent it. Right now I have some very tiny copper pipe acting as a heatsink. The Audi's are surface mounts, too tiny for me to know how to properly soder and have a pretty sophisticated heatsink and electronics to boot. Oh, and the LED's are rated at 20 mA per chip (4 chips = 80mA). What if I try a higher quality 50mA single chip superflux or something similar...is there a comprimise you guys can think of that would be really robust, take the heat and or not put out much heat but still have good output. These are rated for 30000 lumens each but will sacrifice to get them to work properly.


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## VidPro (Sep 17, 2009)

mattchatwin said:


> I admittedly never measured the amps becuase of that very reason, I did check the volts and I had a solid 11.89 v off of the regulator under load and while idle, with the 33ohm resister I had about 9 volts to share between 3 leds in series which is well under the 3.5 v spec of the oznium leds. Color was still good, not a crisp white but acceptable (probably around 5500K). Here's the thing though, I've seen heat rating on these max out around 120 degrees F from most companies but i don't know what these are rated at (oznium couldn't tell me other than they will run fine at the temperature they're rated for....duh, that all depends on a lot of variables).....so when I check the heat outside of the headlights just sitting on my workbench they get as hot as 110, pretty close to the threshold i would say, and with the quantity (15) tight up against the glass they probably don't get much circulation so heat would be an issue unless I get a really aggressive heatsink on them somehow and vent it. Right now I have some very tiny copper pipe acting as a heatsink. The Audi's are surface mounts, too tiny for me to know how to properly soder and have a pretty sophisticated heatsink and electronics to boot. Oh, and the LED's are rated at 20 mA per chip (4 chips = 80mA). What if I try a higher quality 50mA single chip superflux or something similar...is there a comprimise you guys can think of that would be really robust, take the heat and or not put out much heat but still have good output. These are rated for 30000 lumens each but will sacrifice to get them to work properly.


 
run the quad die at lower, is just as good as getting single die and running them high again. 4dies 10ma 40ma total. it has some to do with the Package itself. no mater how many dies they put in, the package they are in has to dissipate the heat. remember that one set of legs on the led has lots of removable heat roaring down it. running more dies at lower currents is more efficient , and will be longer lasting for the phosphors. 

there is 101 ways to heat sync  assemble on round pcb thing with copper cladding, use a fat copper wire , Even if you keep the insulation on it, if you can get the heat motivated away quick, then a slow expulsion of the heat through (even) the insultion of the copper wire is possible.

the math seems right, and at 110* they shouldnt be up and failing so miserbly on you :-( i mean i assume your not running them for 365days , and i have run both quad die and single die for more than 3000 hours, and i get about 10% death rate at the worst (years of sporatic use and drive current) , and the decline in output over time is miserable on the small leds.


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## mattchatwin (Sep 17, 2009)

Thanks for the help. Any idea what and where a "round PCB thing" can be found as that was one of my first thoughts was getting the LED's onto a PCB with some heatsinks built in.


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## VidPro (Sep 17, 2009)

mattchatwin said:


> Thanks for the help. Any idea what and where a "round PCB thing" can be found as that was one of my first thoughts was getting the LED's onto a PCB with some heatsinks built in.


 
well its not like you have to formulate the connetions for some sofisticated curcuit. just get a hunk of board with a nice thick copper , and run it through a scroll saw, blast some holes in it, and use an exacto knife or a dremmel to seperate the stuff you dont want connected.

i know of straight boards that will take those things easy, round ones , i dont know. http://www.moreleds.com/specials.htm the blanks there will take 5mm 8mm 10mm and the small square leds . each "hole" is unconnected , so you drop solder all over it to make the connections you desire, or run a copper strip across, which will solder easily to it. all that gives you is a solid form, it wont give you directally good heat removal, its just a board to hold stuff easily that can be soldered to.

what i did was to run a copper "strip" wire across the back after soldering the leds and making the solder connections. you know with 8mm and 10mm quad die they recommend leaving the Legs uncut after mounting to the pcb, anything metalic that can distribute the heat around, or even moulding in an epoxy or acrylic (so called ice block) just anything that will spread the heat from the hot point, to the air.

oops, was that 110*F or 110*C  big difference


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## mattchatwin (Sep 18, 2009)

Thanks, I'll do some more testing and that was 110 degrees Farenheit.


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## mattchatwin (Nov 26, 2009)

SUCCESS. So far. LED's are much better quality, a little dimmer but working perfectly. Now, all i need to do is figure out how to delay the power as right now it is powered by ignition. What i would like to do is start the car and allow a few seconds for the car to start before the LED's get power. Is there any kind of inline timer that would delay this?


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## Illum (Dec 19, 2009)

*CREE XRE with Dome removed*

Dome underbelly


 



Emitter itself


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## spencer (Dec 19, 2009)

Impressive and very nice.

This thread should be moved to LED I think.


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## Illum (Dec 19, 2009)

that...might be a good idea


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## 65535 (Dec 20, 2009)

*Re: CREE XRE with Dome removed*

Let's see that puppy fired up, I assume you left it in working order?



Illum said:


> Dome underbelly
> 
> 
> 
> ...


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## yo6ial (Dec 20, 2009)

XP-E's, usually, remain functional after dome removal. 
I've noticed that the exterior of the dome is made of some polycarbonate plastic but inside is filled with a very soft and mushy silicone gel.
I had to remove it, once, to get the led to focus in a LuxI type reflector. 

@Illum: 
Would you tell us if you did extra cleaning around the die or it's just how it came out after tearing it apart? 
And if so... how/with what tools? 
Thanks!


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## Illum (Dec 20, 2009)

*Re: CREE XRE with Dome removed*



yo6ial said:


> @Illum:
> Would you tell us if you did extra cleaning around the die or it's just how it came out after tearing it apart?
> And if so... how/with what tools?
> Thanks!



In order for me to reconfigure the LEDs from series to parallel I needed to remove the optics to solder the wires without melting holes in the optics holder. I tried to remove the 8 degree optic holder but instead of removing it by gently rocking it back and forth parallel to the broad side of the LED chip up I gave it a slight twist. 



65535 said:


> Let's see that puppy fired up, I assume you left it in working order?



the color shifted from a cool-white to a Neutral white
With both optics removed, broken dome on left, original cool white on right








I realigned the dome and sealed it down with glue, it should be dry by now...


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## axd (Apr 3, 2010)

This thread is about "Visually identifying LEDS" according to the Welcome Mat, so I'll add my way of _classifying _LEDs: by "UV response".

Different LEDs in my posession light up differently under UV:


ZL H50-Q5: pale green
ZL H501W: orange
ZL H501R: dark red
LF2XT: orange
The UV response will not be unique to each LED, but I think this can be used as an additional "classifier".

From various Photon Freedoms I get no colour: UV, purple, orange and NV green all remain "inert"; same for the PETZL e+Lite. Maybe the "classic bulb type" LEDs do not light up sufficiently under UV, or the stuff around it blocks UV.

-alex-


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