LED direct mounting tutorial

mckeand13

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Feb 12, 2010
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I am planning on building a light using an MT-G2 LED. I need all the space I can get so skipping a Sinkpad for mounting the LED would be very helpful.

I'm just curious if the direct mount concept is as simple as it sounds. The machining is definitely more complicated but that's not an issue for this one.

Following the pictures below as an example, you solder wires on to the bottom side of the anode & cathode. Those will drop down through the driver housing and connect to the driver. The cross pattern is milled in the driver housing for the LED to sit in and center it.

The critical issue would be to ensure there is enough clearance, at least for the positive side, so it never touches the driver housing and shorts right?

The center section stays raised to make the thermal contact with the LED.

In the pictures it looks like the LED's were glued down somehow. I suppose that makes sense as they would try to move around while wiring.

Does the thermal pad get soldered or adhered to the LED to ensure good contact?

Am I missing anything?

Does anyone have other example pictures, experiences, or tips they can share?

Credit goes to DatiLED for the pictures.





 
Last edited:

DIWdiver

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Jan 27, 2010
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Forget the cross pattern. That's for a solderpaste stencil, and the cross is only because they don't want that big rectangle open.

The emitters can be soldered or glued using thermal adhesive. Unless you have some awesome adhesive, solder is probably better thermally, but it can't be done on aluminum. If you are using copper, it's an option.

The "glue' you see is probably thermal adhesive. It's applied liberally to provide as much thermal pathway as possible between the emitter and the base.
 

LilKevin715

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May 25, 2010
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San Diego, CA USA
In the past with larger emitters such as the SST-50 and SST-90 the center thermal pad could be attached to the heatsink with a thermal epoxy such as Arctic Alumina. There are several threads here on CPF about mounting these larger emitters with thermal epoxy. As for preventing the wires from shorting out you can use some kapton tape to prevent shorting combined with some careful soldering. You could also use a non-conductive adhesive/epoxy to cover the solder joints as well.
 
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