LEDs - do you get what you pay for?

[MoFo]

I need to buy some component LEDs for a few projects.  Is there any practical difference between the dirt cheap diodes on eBay (a buck for 50), and the more expensive ones from electronics suppliers (50¢ each)?  

 

Brightness?  Lifespan?

 

They're going to be buried in a model, so I can't replace them if they burn out or dim after a few years.  On the other hand, if they're identical parts, it would be kind of ridiculous to pay 25x the cost.

[skyhawk174]

Hi Mike

 

I bought some LEDs several years ago from a place on line. They only sell LEDs and they seemed okay, they were cheaper than local for sure. As for difference in quality I think there must be but it may be in the LED itself?

 

I have only lit one of my models (with LEDs bought from Radio Shack, yeah it was that long ago) and they still work except one. The one not working is my fault as I am pretty sure a wire is broken to the LED.

 

Are you going to have the LEDs on a lot?

[dnl42]

I suppose the differences are QC and packaging costs

 

It should be easy to see the packaging cost differences between the 50-for-$1 devices v. 1-for-$0.50 devices.

 

Not so sure you can quantitatively evaluate the QC of either device without spending the money and trying them out.

 

I usually go with a reputable supplier. I find both Mouser Electronics and Sparkfun to be reputable; there are others, both online and brick-and-mortar. In any event, Mouser has LEDs starting at $0.06 for red; looks like white starts at $0.39. Sparkfun also has LED choices.

 

I don't work for Mouser, Sparkfun, or an LED manufacturer, just trying to help...

[ESzczesniak]

Agree, I think the main difference will be in QC.  I suspect you may have a few duds in the 50 for $1, but the ones that work will likely not be much different than the 1 for $0.50.

[MoFo]

Yeesh.  I totally missed the replies to this!  

 

 

On 1/25/2017 at 11:21 AM, skyhawk174 said:

Are you going to have the LEDs on a lot?

 

Not really.  The odd display, that's about it.  But they'll be big-ish projects, and I figure the lights would add a neat extra touch.

 

What prompted the question was that reading up on LED quality, there are a bunch of warnings about cheap flashlights.  Basically, they run lower quality components at higher power to produce more light, but that burns the diodes out quickly.  Granted, that's a finished product vs. individual components, but it made me wonder if I can trust what I'm getting when it's suspiciously cheap.

 

On 1/25/2017 at 5:54 PM, dnl42 said:

I suppose the differences are QC and packaging costs

 

There shouldn't be much difference in packaging.  I need a bunch of different sizes, but most are SMD, so they're packaged in reels: 

 

 

Maybe the expensive strips are packaged in a more luxurious zip-top bag?    QC could be a bigger issue though.  Which is kind of my problem.  I don't care if I buy 50 LEDs and only 40 of them work out of the box.  But if the QC issue is a dramatically shortened lifespan... that's a problem.  Guess I should just order a bunch and do some experimenting.

 

On 1/25/2017 at 6:03 PM, ESzczesniak said:

Agree, I think the main difference will be in QC.  I suspect you may have a few duds in the 50 for $1, but the ones that work will likely not be much different than the 1 for $0.50.

 

Good to hear.

[dnl42]

2 hours ago, MoFo said:

Maybe the expensive strips are packaged in a more luxurious zip-top bag?    QC could be a bigger issue though.  Which is kind of my problem.  I don't care if I buy 50 LEDs and only 40 of them work out of the box.  But if the QC issue is a dramatically shortened lifespan... that's a problem.  Guess I should just order a bunch and do some experimenting

Aye, there's the rub.

 

It's more than them working at all (the DOA problem), but also how long they last. Fortunately, once into the flat part of the bathtub curve, which Mr Murphy suggests will be right after the glue has cured, your wiring will be the significant issue.

 

Edited February 3, 2017 by dnl42