led question

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myp71
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led question

Post by myp71 » Sun Jan 11, 2004 9:14 am

Hello,<p>Would you think that 12,000 mcd for a white led is too bright for a general light project?<p>I don't want so bright that it is annoying like at night :eek: <p>Or would maybe 8,000 be better?

L. Daniel Rosa
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Re: led question

Post by L. Daniel Rosa » Sun Jan 11, 2004 12:44 pm

With that rating my only concern would be that the beam may be too narrow. You can always reduce the current to the LED if it is too bright.

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dacflyer
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Re: led question

Post by dacflyer » Sun Jan 11, 2004 7:44 pm

where is this 12k white led? i'd like to see them<p>whats the viewing angle?

jrob709
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Re: led question

Post by jrob709 » Sun Jan 11, 2004 8:49 pm

i don't have any but lsdiodes.com sells a 5mm 12,000 mcd white led for 90 cents.<p>the spec sheet says the viewing angle is 20 degrees at 8000 mcd, no other viewing angle info is listed.

amuron
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Re: led question

Post by amuron » Sun Jan 11, 2004 9:02 pm

Paralight has some that are beyond 12000mcd. However they do not yet have the data on the web site. Gut feel suggests it takes a while to translate. They are spendy and run on something like 350mA. They are similiar to the 150mA units on their website. The rep was here before Christmas, and brought in all the latest and greatest new products. Really cool!!
http://www.para.com.tw/e-product.htm
Ron

myp71
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Re: led question

Post by myp71 » Sun Jan 11, 2004 9:09 pm

Dacflyer-<p>Yeah, they are @ lsdiodes. I tell you what you buy them first then let me know how good they are before I buy them for myself,ok? ( If I ever can get through paypal to order)<p>
Myp71

myp71
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Re: led question

Post by myp71 » Mon Jan 26, 2004 2:03 pm

Ok I went ahead and bought these led's two questions<p>
1) are led's static sensitive?<p>
2) what resistors would I need for 12vdc power I have been using 680ohms just want to make sure that I do not burn them out? if they are different from what I have been using<p>here is the links<p>this is the blue
http://www.lsdiodes.com/5mm/5mmblue.htm<p>and the whites
http://www.lsdiodes.com/5mm/5mmwhitestrong.htm<p>thanks

L. Daniel Rosa
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Re: led question

Post by L. Daniel Rosa » Mon Jan 26, 2004 4:06 pm

The LED chemistry used to make blue and white is static sensitive. I managed to burn four in one day with careless handling, and to my knowledge I've never burned any other ESD sensitive component. OTOH, they're not expensive enough to justify internal protection diodes. About the best I can advise is not to put them into a live circuit, even if it's only 12V, cut the power first.<p>430 ohm will give you the closest to 20mA, but 470 is more common. I've driven the 5mm at 50mA for a while with no adverse effects noticed, but the color shifts a bit while overdriven.

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