In the summer months leading up to my first major log, I learned a lot about the future of electronics. The fact is, the world is getting efficient and one method of getting there is going to be increased usage of GaN devices. For this reason, I've built my latest revision of the Pi-ESC system around a GaN design. Fast transients, fast signals, and fast cars!
So, here is the board. Files will follow after I sort them out.
On paper, the components can handle 20kW continuously! With the pitiful amount of copper I had within the board area of a Raspberry Pi and 4 layers, and 4 ESC channels, I would conservatively rate the board at 2kW. At 99% or so efficiency, that's just 20W of power that needs to be dissipated, meaning you can reduce the weight contributed by a bulky heatsinking solution.
Almost no area is spared from being functional. Where large area is unused, like the center of the bottom side, many solder apertures on the copper forms a solder or high emissivity heatsinking structure. When painted or coated with a high emissivity material like carbon conductive assembly paste (stencil applied carbon resistor material), improved thermal performance will result because of its very high emissivity.