What is COB?

COB stands for chip on board. this means that all of the leds are mounted on the pcb.

Why COB?

Cob delivers the same efficiency and brightness as some cree leds but at a much lower cost. This means that they are much better than 5mm leds in brightness and efficiency while still maintaining a low price.

Step 1: A Useless Product

At Dollarama i found this:

A cheap led light. This product is poorly designed as there really isnt any function for it.

Since it uses Triple A batteries the light only lasts for an hour,

What is good about this is that it is cheap and it has some bright cob leds.

Each cob only costs 1.75 CAD

Step 2: Extracting the Leds

This is a very simple possess. All that has to be done is to remove the screws. Then the enclosure would come easily apart.

The leds are now ready to be de-soldered and used.

Step 3: Uses

Unlike your normal 5mm leds which are highly inefficient and dim Cob leds are much better. They can handle much more wattage and can also be easily cooled.

I used 3 of them to create a led light bar.

<p>They must be driven in constant current. They have a variable threshold voltage (between 3 and 60 volts depending on their architecture), batteries cannot last because their voltage decreases under 3V quite fast. But when batteries voltage is converted in constant current they last far more.</p>
<p>How does the price compare to eBay? You can certainly get it quicker at your local dollar store.</p>
The price per cob is roughly the same as the price on ebay

About This Instructable




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