When I was working on the new layout for the TMC2660 branch of the board, I used a dedicated ground plane and turned out this was awesome. It simplified lots of the routing as well as added good heat dissipation capabilities to the board.
I wanted to try and redo the layout of the TMC2130 branch with this technique. In addition I wanted to swap the location of the E1 motor driver and the 5V input connector, before the E1 driver was crammed in the corner and it was challenging to get good routing of the power pins. By swapping the position with the 5V power connector there is a bit more space.
The third thing I wanted to try was to reverse the position of the STM32 NUCLEO board – in the previous design it was sticking out in an unsightly manner.
So here it is new layout all complete. DRC checks pass.
In a slightly different perspective:
You can see the NUCLEO does not block the mounting hole on the lower left corner anymore (MK4).
Here is a look from the bottom:
The motor driver have large area on the bottom for heat dissipation. You can also see the large rectangle area on the bed heater control MOSFET on the top.
I also added a few extra power connectors – two for Vin and two to the 5V rail, to hook cooling fans for the case. You can see two of them on the low left corner in the last picture.
Note: while the last picture shows the STM32F411 CPU, the board actually required the STM32F446 version. The only 3D model I found for the NUCLEO STM32 dev kit was with the STM32F441 part, so that is why it is on the images.