# LED question



## bulbski (Aug 25, 2011)

don't know much about LED bulbs but need to buy 9006 LED bulb for a car and maybe someone can answer cpl questions. 
1. is there such a thing as 3 chip led?
1.5 if there is 3 chip led, is it better than regular SMD ones?
2. does more led's mean brighter light?
3. is there a big difference between having 120leds vs 60?
Thank You


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## Norm (Aug 25, 2011)

Moved to Transportation Lighting - Norm


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## evilc66 (Aug 26, 2011)

bulbski said:


> don't know much about LED bulbs but need to buy 9006 LED bulb for a car and maybe someone can answer cpl questions.
> 1. is there such a thing as 3 chip led?
> 1.5 if there is 3 chip led, is it better than regular SMD ones?
> 2. does more led's mean brighter light?
> ...


 
1. Yes
1.5 Depends on what you mean by a "regular SMD" LED. There are a lot of sizes of LEDs, big and small. Multi chip LEDs like that are typically on the larger side, as larger LED packages deal with heat better.
2. Typically, yes, but there are many factors that determine brightness.
3. Depends a lot on how thing are set up. It's all dependant on the drive current for the different setups. If a 120 LED array and a 60 LED array are run at the same current, then the 120 LED setup will be twice as bright. If the 120 LED array is running at about half the current of the other array, then they will be close to the same brightness.


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## blasterman (Aug 28, 2011)

I didn't realize it but there actually are 9006 LED retrofits, which I can't begin to state the problems with this kind of retrofit.

Hey Evil, I think he was referring to these: 

As we both know any attempt at determining brightness is frought with engineering peril. First, we need to know the quality and efficiency of the SMDs in use. This variable alone can vary 50% if they are high quality SMDs, which I doubt given the sources and emphasis on things like '3-chip' LED. Assuming 120 or 60 LEDs this has to be 5mm LEDs or smaller.

Next we have the issue of putting a quasi cylindrical shaped light source inside a reflective chamber designed for a halogen filament, which means you have no idea what's going out the front or what direction. OTF lumens? Got a Ouija board? 

Checking the specs on several of these bulbs they seem to range from 2-4watts. My guess is those here might be around 250 total lumens. You simply have no place to push the heat so I can't imaging them being brighter.


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