# Seoul P4 is not [email protected] !?



## mailint (Sep 24, 2007)

This page http://www.leds.de/product_info.php?info=p266_Seoul-Z-LED-P4-Star--wei---240-Lumen.html lists the Seoul Z-LED P4 as being 119lm @350mA when the official data sheet at http://www.seoulsemicon.co.kr/_homepage/home_kor/product/spec/W42180.pdf only says that the best performance group (U rank) is min. 91lm, typ. 100lm.

Am I missing a new version of the P4 or this is false advertising?


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## Szemhazai (Sep 24, 2007)

They are simply selling them with *maximal allowed* by SSC specification Lumen rating - U bin range is 91-118,5 lum @350mA .


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## mailint (Sep 24, 2007)

Szemhazai said:


> They are simply selling them with *maximal allowed* by SSC specification Lumen rating - U bin range is 91-118,5 lum @350mA .


 
Hmm.. where did you read that there's a maximum allowed? 
it seems strange to me... what does SSC do with [email protected] LEDs? do they throw them away?


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## Szemhazai (Sep 24, 2007)

Read between the letters - *allowed by SSC specification* so if you have U bin SSC leds u can sell them as 91 / 100 / 105 / 110 / even 119 lumens @ 350mA .

And nobody can say that you are cheating customers :naughty:


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## 270winchester (Sep 24, 2007)

a 2.0 liter 4-cylinder piston-driven internal combustion engine can make a maximum of 1000 horse power under optimum condition with lots of boost.
.

doesn't mean a commuter car has 1000 horse power.


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## coolwaters (Sep 24, 2007)

270winchester said:


> a 2.0 liter 4-cylinder piston-driven internal combustion engine can make a maximum of 1000 horse power under optimum condition with lots of boost.
> .
> 
> doesn't mean a commuter car has 1000 horse power.





boost? u mean rocket boost??


anyways if u look at the charts u can see that the LEDs will become more efficients at low temperature.


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## chris_m (Sep 24, 2007)

mailint said:


> Hmm.. where did you read that there's a maximum allowed?
> it seems strange to me... what does SSC do with [email protected] LEDs? do they throw them away?


If they made them then you'd find V bins in the shops.


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## daveman (Sep 24, 2007)

Almost all (possibly all) LED manufacturers state their emitter's output in ranges, SSC is no exception. HOWEVER, SSC P4's have such huge range in output, in the same bin, that the customers really don't know what they're getting for their money. This was one of the few flaws of Lumilled's old Luxeon line and, conversely, is also what makes Cree stand head and shoulders above SSC at the moment: tight, really really tight binning range.


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## mailint (Sep 25, 2007)

Sorry all but I don't agree, even reading between the letters.
We all know that we can bring the Seoul P4 U rank up to 240lm @1000mA and even more at superior currents but this doesn't authorize me to seel it as 240lm *@350mA*!!

As far as I know all the single leds have an unique lumen value at a specific current value. Can someone prove that this statement is wrong?


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## Szemhazai (Sep 25, 2007)

Now read once more SSC Data Sheet, page 4, Note [1] :


> *[1] SSC maintains a tolerance of ±10% on flux and power measurements.*


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## LEDcandle (Sep 25, 2007)

mailint said:


> Sorry all but I don't agree, even reading between the letters.
> We all know that we can bring the Seoul P4 U rank up to 240lm @1000mA and even more at superior currents but this doesn't authorize me to seel it as 240lm *@350mA*!!
> 
> As far as I know all the single leds have an unique lumen value at a specific current value. Can someone prove that this statement is wrong?



Huh? I don't get it ... SSC specifies 91-119 lumens @350ma, so a manufacturer says 119 lumens @ 350ma; I think that's fairly reasonable. At least he didn't inflate it beyond specs or use trick marketing like "Uses a powerful LED capable of 240 lumens!" or "Output : Up to 240 lumens!"... which is also theoretically correct, but not ethical. 

What 240lumen @ 350ma? 

Anyhoo, if there are SSCs above 119lumen, they might probably be stashed aside as V-bins. That's what I would think. Maybe that's why sometimes LEDs vary so much within the same flux bin because some might be overperforming lower bin LEDs while others might be 'true' bins in that range... just thinking aloud...


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## mailint (Sep 25, 2007)

Szemhazai said:


> Now read once more SSC Data Sheet, page 4, Note [1]:
> 
> *SSC maintains a tolerance of ±10% on flux and power measurements.*


 
The data sheet only mention min. 91lm and typ. 100lm @350mA. With ±10% tolerance.

And you would call seeling them as 119lm @350mA ethical??


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## mailint (Sep 25, 2007)

LEDcandle said:


> Huh? I don't get it ... SSC specifies 91-119 lumens @350ma


 
NO. Please tell me (if you want to be believed) where you read that 119! 
The data sheet only mention min. 91lm and typ. 100lm @350mA. With ±10% tolerance.

Now, I guess that SSC would put an hypothetic [email protected] P4 still in the P4 line (and in the U performance group, since the data sheet doesn't report a maximum for it and don't introduce a V perf. grp).

This doesn't authorize a seller to advertise them as [email protected]!
otherwise why don't they write [email protected]? the data sheet doesn't exclude the possibility that a [email protected] can be put in the P4 line (and U perf. grp.).


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## Szemhazai (Sep 25, 2007)

It marketing babe... **** or be ****ed . If you are selling something and advertising that basing on technical specification given by the producer it's his responsibility not yours.

You have all data given in datasheet :
±10% tolerance
constant temperature 20*C
measurement is taken during short impulse to not overheat the die

Under those conditions, everything that is in datasheet may be true - unless you cant prove that is otherwise. If you can't achieve such efficiency at home it is your problem - you are not preserving lab conditions...


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## LEDcandle (Sep 25, 2007)

I don't know where their sources are from, but a few instances of 118.5 lumens have come up... 

http://flashlight-forums.com/index.php?topic=4988.0

well, theoretically, it doesn't sound too far off. Even if it were 10% variation from typ 100 lumens, that would be 110 lumens. Another 9 lumens isn't considered a ridiculous brag, I would say. 

As I said, it isn't too much of a crime claiming 119 lumens from the SSC at 350ma.... better than them misleading the uninformed public something along the lines of "240 lumen LED".


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## mailint (Sep 25, 2007)

Ok people.
Here in Italy they would be easily condemned from the Agcm autority for deceptive or false advertising (edictal sanction of 5000 to 500000 euro) unless they would prove that the P4 that they normally sell are [email protected] with a strict margin. Yes, we have an inverted onus of proof for the deceptive advertising process.
I'm sorry to hear that there is not the same.


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## SemiMan (Sep 25, 2007)

It clearly says "Luminous Intensity Max." which accurately would be 119lumens. Is this perhaps the most relavent measurement? I think most of us would agree it is not. Ethical? I think that is the question. Those less experienced may not understand the measurements and to that end, perhaps it is not fair. Note that typical (and max) are given for forward voltage. Obviously the typical forward voltage is more flattering then the maximum.

Semiman


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## mailint (Sep 25, 2007)

SemiMan said:


> It clearly says "Luminous Intensity Max." which accurately would be 119lumens.


 
Error 1: it doesn't says "Luminous Intensity Max". Here people seems to see what they what where they want... I'm stunned..
Error 2: the max luminous intensity of the SSC P4 is not 119lumen. A normal P4 can go over 200lumen at proper current (surely not not 350mA) and within the specifications.


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## chris_m (Sep 25, 2007)

mailint said:


> Error 1: it doesn't says "Luminous Intensity Max". Here people seems to see what they what where they want... I'm stunned..
> Error 2: the max luminous intensity of the SSC P4 is not 119lumen. A normal P4 can go over 200lumen at proper current (surely not not 350mA) and within the specifications.


1. It quite clearly does say "Luminous Intensity Max" - immediately before the "bei 350mA 119lm".
2. See the end of my point 1 - they specify the current, and also give a higher 1000mA figure.

I suggest you learn to read better before getting out your flamethrower.


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## mailint (Sep 25, 2007)

chris_m said:


> 1. It quite clearly does say "Luminous Intensity Max" - immediately before the "bei 350mA 119lm".
> 2. See the end of my point 1 - they specify the current, and also give a higher 1000mA figure.
> 
> I suggest you learn to read better before getting out your flamethrower.


 
"Color: white
Luminous Intensity: bei 350mA 119lm, bei 1000mA 240lm"
Viewing angle: 125°"

Where do you exactly see "Max" in this text?


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## chris_m (Sep 25, 2007)

mailint said:


> NO. Please tell me (if you want to be believed) where you read that 119!


It's in the binning guide - straight off the site selling that LED http://www.leds.de/media/products/0349526001175432269.pdf

If it was more than 118.5 it would be a V-bin, not a U-bin.

Strictly speaking, by claiming 119 max rather than 118.5 max I think that would also fall foul of advertising regs in the UK.


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## chris_m (Sep 25, 2007)

mailint said:


> "Color: white
> Luminous Intensity: bei 350mA 119lm, bei 1000mA 240lm"
> Viewing angle: 125°"
> 
> Where do you exactly see "Max" in this text?


Where's that text from? At the original link http://www.leds.de/product_info.php?info=p266_Seoul-Z-LED-P4-Star--wei---240-Lumen.html it says:

"Color white
Luminous intensity max. bei 350mA 119lm, bei 1000mA 240lm
Viewing angle 125°"

(cut and pasted straight from there - minor editing, but nothing added!)


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## mailint (Sep 25, 2007)

chris_m said:


> Where's that text from? At the original link http://www.leds.de/product_info.php?info=p266_Seoul-Z-LED-P4-Star--wei---240-Lumen.html it says:
> 
> "Color white
> Luminous intensity max. bei 350mA 119lm, bei 1000mA 240lm
> ...


 
Oh, now it's different than when I wrote my last message! I suspect that the version of that page oscillated during the last hours.
Perhaps it was the effect of the claim I sent to them yesterday 

And the data sheet at http://www.seoulsemicon.co.kr/_homepage/home_kor/product/spec/W42180.pdf only reports the T and the U rank... I didn't find that other document on the Seoul site.


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## chris_m (Sep 25, 2007)

mailint said:


> Oh, now it's different than when I wrote my last message! I suspect that the version of that page oscillated during the last hours.
> Perhaps it was the effect of the claim I sent to them yesterday
> 
> And the data sheet at http://www.seoulsemicon.co.kr/_homepage/home_kor/product/spec/W42180.pdf only reports the T and the U rank... I didn't find that other document on the Seoul site.


I shouldn't have been so hard on you - ISTR the same thing - they must have just changed it (and maybe you had a cached version). That binning note is on the Seoul site http://www.essc.co.kr/_HOMEPAGE/home_kor/product/spec/P4_BL.pdf under documentation near the top of http://www.seoulsemicon.co.kr/_homepage/home_kor/product/product_P4series.asp?topCODE=2&midCODE=4 (though I couldn't find it earlier as some of the Seoul site gets blocked in work).


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## mailint (Sep 25, 2007)

chris_m said:


> That binning note is on the Seoul site http://www.essc.co.kr/_HOMEPAGE/home_kor/product/spec/P4_BL.pdf under documentation near the top of http://www.seoulsemicon.co.kr/_homepage/home_kor/product/product_P4series.asp?topCODE=2&midCODE=4 (though I couldn't find it earlier as some of the Seoul site gets blocked in work).


 
Oh, now I understand why I didn't find it by searching it with Google with the key "site:seoulsemicon.co.kr"


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## chris_m (Sep 25, 2007)

mailint said:


> Oh, now I understand why I didn't find it by searching it with Google with the key "site:seoulsemicon.co.kr"


Yeah, I was trying much the same thing, and having much the same problem due to the Seoul site not working properly in work. BTW are you using Firefox, since it's never worked properly under that? You have to downgrade to IE


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## mailint (Sep 25, 2007)

chris_m said:


> Yeah, I was trying much the same thing, and having much the same problem due to the Seoul site not working properly in work. BTW are you using Firefox, since it's never worked properly under that? You have to downgrade to IE


 
I'm using IE7 under XP and Vista and the english version of their site is always broken (tried in the last days): I get a window dialog with an error and the frame under the subject remains blank.
This is why I searched from Google...


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## chris_m (Sep 25, 2007)

I have a feeling newer versions of IE may also be a problem - doesn't seem to be just the blocking that's a problem in work with IE. Works fine with IE6 here (one of the few reasons I use it is to check out the Seoul site).


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