I've spent the last month testing and demolishing a bunch of new-design thermal PCBs from SinkPAD, and have come to the conclusion that this is a solid solution versus traditional dielectric PCBs commonly used for mounting LEDs. There are many pros, and a few cons, and I will address these in my review of their product, written below.
We will start with the good stuff first, the Pros. The SinkPAD Direct Thermal Pathway PCB is made from solid aluminum or copper (as of the time of this writing I had yet to test any copper PCB), so it's very good at thermal transfer. This helps make it easy to solder; versus a traditional dielectric board, the solder took to the SinkPAD in roughly half the time. This also comes in handy for reflow work and rework, as mounting and un-mounting an LED from the board is quick thanks to the PCB being constructed out of high-conductivity aluminum and copper. Repairing any mistakes takes minimal time and effort, a must for any prototype designer or hobbyist. The solder resist is also very solid, during my reflow cycling test I never once saw a solder bridge form, nor had any shorts. The same solder resist is quite durable against thermal shock as well. I torched it until it was smoking and crackling, near-black, and with no problems I was able to mount an LED to it and light it right up, and the remainder of the pad transferred heat exactly as it should. This durability is exactly what the military and police forces could use for LED-assisted weapons solutions, such as barrel or grip-mounted lights, or IR night-vision equipment. The aluminum boards are light-weight and stiff, very difficult to bend, even with a pair of clamps and pliers and my full weight applied.
Now for the cons. Due to how the thermal pathway is manufactured, there's an indentation on the back of the board. This means you need to use more thermal paste/epoxy, and you need to be more careful not to introduce air bubbles and gaps. On the aluminum boards, there is no solder pad on the back side, which would help greatly since solders tend to be more conductive than thermal pastes and adhesives. The copper board likely wouldn't need it, since copper is easy to solder. Speaking of copper, there are a distinct lack of copper options for many of their PCB choices. While this is understandable (many of these LEDs simply don't need it) the ability to have broader choice in materials would be nice. My final bad note is the difference between prototype boards I have versus some of the production boards. An older X-Lamp XR-E board had four screw holes for improved mounting, and they were placed so that most screws that could fit those holes would not have the heads short out on the contact pads. These holes are nonexistent on the star and disc boards. The star have their electrical contact points too close to the indents at the outside to allow screws to be attached there, but the circular boards look like they might have a better chance.
Overall, this is a solid piece of thermal management tech for LEDs. The ease of use and durability should appeal to a wide variety of LED consumers, from hobbyists, designers, and engineers to police, military, and even more groups of people and industries. Most of the cons are personal nitpicks and aren't exactly game-breaking important, and the pros certainly outweigh any con I've been able to notice. Highly recommended.
