3W-9W RGB LED - Common Anode PRODUCT ID: 2524

[adafruit_support_mike]

If you have the space for it, you can use the same kind of heatsink you'd find on a computer's CPU. The fan is optional, but wouldn't hurt.

The aluminum base under the LED is also a heatsink, and will give you good thermal transfer to another one if you use thermal tape:

https://www.adafruit.com/product/1467

The base is 20mm across the flats, so you'd want at least a 1" square.

[adafruit_support_mike]

Use power mosfets instead of Darlingtons. There's no comparison. A good power mosfet has a channel resistance below 10mohm when it's fully turned on, and will drop less than half a volt under extreme current loads. A Darlington has a minimum voltage drop of about 1V at any current level large enough to warrant using one.

There are still good reasons to use Darlingtons, but they're in low-power applications where you need as much current gain as possible in the smallest space possible.

[adafruit_support_mike]

Sorry, which 'these' do you have in mind?

[adafruit_support_mike]

Thank you.

You can sign up for in-stock notification on the product page, but we don't do ETAs beyond that. There are too many sources of delay in the supply chain that we can't control, and *way* too many people on the internet who think 'estimated' means 'guaranteed'.

[adafruit_support_mike]

We talk about pre-orders periodically, but most of our delays are constrained by production.. either ours or the vendors who sell us parts.

With that kind of limit, pre-orders would end up generating messages like, "Thank you for your order. All units from the next X weeks of production have already been pre-sold, and your order will be fulfilled from the production lot scheduled X+N weeks from now. Please be aware that the production date for that batch is only an estimate, and may change without notice."

On top of that, the accounting rules for pre-order payments say we can't take any money until we actually ship the goods. We wouldn't actually be selling things faster or making money earlier than we do with the current, "make stuff, sell it until we run out, then stop selling until we make more" model.

[adafruit_support_mike]

The drilling was easy but the tapping was where it went south (as it usually does with small fine threads even in aluminum).

I've been doing some small mechanism work lately, including 0-80 and 00-90 screws, and yeah.. you can strip those things by looking hard at them. Brass is pleasant to work at that scale, but is pricey.


Your build looks good! Thanks for posting the photo.

[adafruit_support_mike]

Looking good..

Adding a fan will still help if you have the space for it. The primary failure mechanism in LEDs comes from flaws in the crystal lattice. Those increase the resistance of the semiconductor and interfere with light production. The flaws are caused by current pushing on the atoms (known as the 'electron wind'), and they occur more easily as the temperature gets higher.

LEDs carrying a lot of current will gradually develop flaws which reduce the light output and increase the resistance. The increased resistance generates more heat, which makes the next flaw happen a little faster, and so on. It's an exponential process which starts slow and increases gradually, then hits a critical point and rushes to complete failure in a few seconds.

Keeping the LEDs as cool as possible will help them maintain brightness and last longer.

[adafruit_support_mike]

Looks great.. thanks for posting the photo of the end result!