Can the 5v output from the feedback io (and ground) be used to power a microcontroller + low draw boards (2x hx711) or even the 5v pin + ground in misc IO? should be well under 600mA (150mA I think). I cant use the isolated IO pins in output mode as I need to switch power sources regularly (and am squeamish about hardware modification).
Sorry if this in in the documentation or been already answered, and thanks for such a great product and support.
Glad ODrive is working out for you 
and this should definitely be added to the docs!
Pro has a headroom of a couple hundred mA on the 5V rail - we haven’t done specific tests with this, but 150mA should be fine, and 600mA is quite high but shouldn’t cause issues – though I’d definitely try to keep it below 250-300mA if possible, since higher draws under long periods of time haven’t been tested.
Note that this can make you very susceptible to ground loops - definitely something I’d be very very very careful about when designing your system!
Thanks, I completely forgot about ground loops, is it because of the isolated ground being isolated? (I guess this is a dumb question sorry). I have a bad history with electronics going poof so will use a separate power sauce for now, but I guess the correct solution is the hardware modification. Thanks again.
If I did perform the hardware modification and used the now 5v output would the output logic (uart) be 5v if the input logic was 3v; I need 5v for my amplifiers but teensys are only 3.3v tolerant, I assume it would be 5 vaults damm guess il have to get my head around ground loops.
If I attach a 5v converter to the 6s lipo in parallel to the odrive will it create a ground loop or any other problems?
It is another piece of hardware but would allow me to power my teensy directly through its usb so there is no risk of connecting two power inputs to it. (helps when a mistake cant be made lol)
Sorry, what hardware modification are we talking about here?
The main risk here is that now nothing’s able to connect to both the Teensy and the Lipo without causing a ground loop – so everything has to be powered from the Teensy.
You should be able to set up a correct system without much issue - I’m having a bit of trouble understanding exactly what you’re trying to do – could you sketch out a schematic / wiring diagram for the ODrive, Teensy, sensors, etc? Then it should be easy to see if there’s an issue.
Overall I don’t think there’s an issue with using a dedicated 5V buck for the Teensy – likely what I’d do, since powering from the ODrive means you need to be a bit careful with future system changes/additions (e.g. current limits). If you sketch out your wiring diagram, ground loops are easy to find - if the grounds in your system has any cycles, that’ll cause a ground loop. Note ISO_GND to DC-/GND on the ODrive won’t be a ground loop, since it’s isolated.
When in doubt, sketch out the schematic and ask here always happy to look at something.
I made a sketch of my current setup; are there any ground loops as it is? used for some time with no apparent problems. So can I use a 5v buck off the Lipo ,in parallel to the odrive, connected to the 5v and ground on the tennsy and use the same pin for 5v on my amplifiers (the same I am doing when powered by usb).
Thanks again
Sure, this looks fine, as long as the VIN/GND you have there on the ODrive are the ISO_VDD and ISO_GND. Only thing I’d be careful of is powering the teensy from USB and the buck at the same time - not sure if that can damage the teensy, you’d have to do some research.
thanks, your right the tennsy would need a modified usb cable if I wanted telemetry whilst its being powered by the buck.
