What does the simplest 3D printer main board need?
Well the task of making a main board is incredibly complicated, that's why it needs to be as simplified as much as possible. The schematic of Ender 3 motherboard is a good reference I feel. Because they wanted to cut costs everywhere they could. That includes a main board.
Cant see much here, however that's the whole board, and it's not too complicated. It's an old board released in 2020. So my guess is that I do need to add a bit extra than those components, just to make it not lame. I forgot to specify that this schematic is just for component references. Cant copy it, because the controller will be different and drivers probably, and maybe voltage regulator.
TMC2240 is a nice choice for motor driver, however it is a bit expensive. The chip itself it $6.6. A good budget choice is TMC2209 for $2.7. It's an older version than 2240, but it's cheaper and for first build it will be good enough. I'm sure there are a lot of other options that I don't even know about because I haven't done a proper research. But that's a battle for the future when and if I get this board done.
Jyers
[1] Schematic of a Creality 4.2.7
