Hi, do we have a chance to add emergency button to drv8301 ? i dont want to power off stm microcontroller.
I’ve accomplished this in the past by building a circuit that when the estop is pressed it switches the odrive’s power from VBus (24 or 48 volts) down to 5 volts using a relay. It’s necessary to have a diode on the lines so that the caps don’t drain VBus in to your lower voltage supply.
This should only be tried if you fully understand the circuit and assume the risks.
The 5 volts triggers the low voltage error on the DRV and instantly stops the ODrive from spinning.
Hacky, but worked for me
v4 has an enable line that can disable the motor PWM without any firmware action, but it needs to be configured at startup and that hasn’t be setup yet. But it will be!
several years ago, we have a product need some SAFE function like this, need cut motor off very reliable.
so we develop a 2-relay on board, to cut MOTOR UVW (2/3)lines trigger by external signal.
FYI
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Yes, this is a better approach IMO, if you have big enough relays.
You could use a 3P-DT relay which has the ODrive on one side, and shorting links on the other. So the motor would stop dead.