Hello everyone,
I have an implementation question for controlling the ODrive S1 with an external Arduino RP2040 board. I have read and respect the issues on ground loops in this type of application and want to make sure my head is in the right place. My Arduino can be powered by wired in 5V is it possible to use the 5V output from the ODrive to power the Arduino. Typically this 5V output would be used to power encoders and or the ODrive’s onboard microcontroller. Does this mean this 5V is resistant to the ground loop issue and I can power my external Arduino off of this source, or will I still need an isolated DC to DC? I am implement UART control from the Arduino to the ODrive.
Thank you
Hi there!
You can absolutely use the S1’s 5V output for powering the RP2040. The only thing to note is that the ground of the RP2040 and other sensors shouldn’t be connected to other grounds in the system – e.g. if you connect USB to both the RP2040 and S1 at the same time (without a USB isolator), that’ll cause a ground loop. That being said, as long as there aren’t any loops created (essentially just making sure the RP2040 doesn’t connect to anything with a ground reference to DC-), you should be just fine. If you’re unsure, feel free to sketch out a quick wiring diagram and send it my way!
Essentially 36V input to the ODrive S1. I then use the 5V produced to power the rp2040 that is connected via RX and TX for serial communication. The ground for the RP2040 is the GND provided on the ODRIVE IO as well. Do I need any more isolation here?
Nope, all looks great! Keep in mind you still have to power ISO_VDD/ISO_GND even if it’s just from the 5V/GND going to the RP2040. Only thing to note is that if you have other things connected to the RP2040, they should be powered from the RP2040 and not connecting back to the battery GND except through the RP2040, or you could cause a ground loop.
