# COB vs SMD



## apollo77 (Aug 8, 2014)

Hello Professionals,

To my best knowledge, heating is the #1 enemy for LED technology.
Having said that, COB should generate more heat due to the fact that multiple "chips" are packed closer compared to SMD.
If heat management is left out of this equation, COB should have a shorter lifespan and prone to other premature failures.
So how are COB better than SMD in terms of stability and lifetime?

In my case of LED street light, COB type would definitely under perform and create many issues without properly designed modules and heat sink. (IMO)

Any advantages to bypass SMD and adopt COB?

Would really appreciate your expertise on this topic!

Ryks*​*


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## yazovyet (Aug 16, 2014)

COB allows you to pack more light/heat/power in a smaller area. That's pretty much it. 

If you need to pack that amount of light in a small emitting area then use COB (but make sure this small little area gets the heat pulled away). If you want to make a larger fixture or have more emitting area you can used SMD or more COB units each at lower power. By virtue of the large fixture and heat dispersed over a larger area you'll not have to worry as much about cooling with nice fins or fans and such.


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## Amy sunshine (Aug 18, 2014)

COB
has a softer light and higher brightness than SMD
SMD
has a small volume, light weight, and high density assembly

In my opinion, SMD is more popular than COB, and the usage is more widely.
so SMD is better than COB?


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## bshanahan14rulz (Aug 18, 2014)

I would guess that SMD vs COB, SMD has a lot of other benefits too. Price is always a factor, and if you manufactured LED bulbs, it would be cheaper to use the same SMD LEDs in differing numbers in all of your bulbs than to design each bulb with a specific COB array for each class of LED bulb. So, be careful when trying to make a correlation with what's common and what is best.


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## DIWdiver (Aug 18, 2014)

Depends on what kind of light you are making. COB puts a lot of light in a wide cone. SMD can do that, or can do very tight cone, or can do omnidirectional (with multiple emitters).


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