Klipper Toolboard

A very small 3D printer board for use on a toolhead. So far it is totally untested and most likely does not work.

Features:

• TMC2209 driver
• ATmega168
• Two MOSFET drivers fans
• One big MOSFET driver for a hotend heater
• Thermistor input
• One servo
• One endstop

It should be fed from the mainboard with 12-24V, 5V, GND, UART RX and UART TX.

Possible issues:

• Is the cooling for the TMC2209 adequate?
• How well will the UART cmos/ttl level survive? Noise?
• Does it work

Alternative design options:

• Use an ARM instead? STM32F030
• Create a local 5V/3.3V instead? Switch regulator + LDO. Only the servo needs 5V
• USB-c would be neat, it could provide all the power and signalling needed