I have the V3.6 and it works great, even though I had to solder the .022uF capacitors on the cables for both motors (that was a real pain). I want to hook more up to the board including a Raspberry Pi, but I can’t seem to find any specs on the chips on the boards, specifically the voltage regulator and its current output; I need to power the Raspberry Pi and other circuitry, but I would just like it all powered of the same 36V lithium battery, with minimal amount of additional components.
Also, I see the spreadsheet on the pinouts for the 3.5 but don’t see the 3.6 anywhere, I am assuming it isn’t much different?
Also, I would like to know the best recommendation for connecting a charging system up to the battery also, that would be able to work with the board so I can just plug the whole thing in to charge, or have it charge through solar power; I am having a difficult time doing that though as your board schematic doesn’t seem to show how the power is being created.
The 5V rail is created by a buck converter on the DRV8301. The maxmum current is listed on the DRV datasheet at 1.5A, so you can’t power a Raspberry Pi with it. I would recommend either splitting the 36V battery into two rails - one for ODrive, and one for everything else - or just running two batteries.
Your BMS will handle charging the battery - you can leave ODrive plugged in, as long as the charging voltage stays below the rated value.
Thanks for the info! Could you please direct me to the link that shows the DRV8301? Was that on the schematic PDF for the V3.5? Also, what is the power consumption of the ODrive when both motors idle and is there a sleep mode or do I have to implement all that myself outside the ODrive?
Yep, it’s in the schematic: https://github.com/madcowswe/ODriveHardware/blob/master/v3/v3.5docs/schematic_v3.5.pdf
I don’t know the answers to the current draw questions, sorry. You’ll have to test it yourself I think.
I’m looking at the schematic PDF again, and I see that U4 appears to be the DRV8301… but I don’t see how you figured out that was the chip… where is the rest of the information that would show that, all I see is U4?
I see it is both U4 and U5 but there is no BOM for the schematic; doing a search the BOM for older boards it does show up though: https://github.com/madcowswe/ODriveHardware/search?q=drv8301&unscoped_q=drv8301
Just not sure how anyone is supposed to find that and why not just put it right in schematic?
Good question. I thought it was in the schematic, but apparently whoever did the schematic didn’t label it with a part number. I’ve just been around long enough to know (roughly) what components are on the board
Probably because the BOMs from 3.4 on are very similar. 3.5 was basically a 3.4 with a 4-layer board, and the 24/48V variant just changes the capacitor voltage ratings as far as I know.
Thank you for all your help! I really would like to be able to power the ODrive on and off using a bank of Mosfets, or just a regular switch to start; are there any typical switches that people use to hand the power, like an example part number? Just wondering how much amperage and voltage (well up to 40+V with this lithium battery) it would take; I would like the Raspberry Pi to be able to shut off the ODrive when not in use and don’t want to use a relay; also that spark when plugging power in, have to maybe put some protection diodes in there possibly… any ideas or existing circuits that people have already built would be very helpful.