I have an Orange Pi which I would like to use as the computer for a robotic project. It supplies around 15 mAh power directly from the board, barely enough for a single LED so I will have to use a motor controller and an external power supply.
My question is, is there a limit to how big of a motor I use with this small orange Pi zero? As long as I have the appropriate power supply and controller for the motor I feel it shouldn't be an issue.
What are some things to keep in mind?
Dependings on what type of motor driver you use...
If you drive transistors directly from an orange PI output, you need to make sure that the PI can supply enough current to saturate the transistors (this is mainly true for BJT type transistors, less problematic for FET or IGBTs, which you most probably drive with a transistor driver).
If the transistor gates are not driven directly (e.g. are optically isolated or you have a transistor driver IC) by the PI you only need to make sure that the voltage levels of the PI and the IC driving the transistors match.
If the motor driver is driven by an analog signal (e.g. 4-20mA signal or 0-10V signal) driving it directly from the PI will probably be problematic since max current for the first case or max voltage for the second case probably cannot be achieved.
If there is a communication protocol between the transistor driver and the motor driver unit, maximum current will definitely not be an issue. In this case you need to match the communication protocol pins (e.g. i2c or SPI)
