This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

DRV8304: Phase action under no load

Part Number: DRV8304


Is there some feature in this DRV that disables it when it senses no load across the phases?

If not, does the DRV do anything at all when motor phases are not connected but everything else is connected and is working correctly? (PWM from microcontroller, hall sensors, and DRV set to 3x PWM mode, mainly)

Thanks for the help,


  • Hi Vishnu, 

    To determine what's happening in the system, I would suggest to check the status of 'nFAULT' pin during various states of operation

    • example: if you are powering up the device and then send PWM signals (with no load connected), does the nFAULT pin pull LOW to indicate a fault has occurred? 
    • Question: what device variant do you have? the SPI variant or the HW variant? having the SPI variant may help make debugging a bit easier, since you can read out the specific fault bit flag using SPI read command 

    These are the fault categories that could occur, which would disable the device outputs

    The same faults have covering in the hardware device variant, they're just not reported through the SPI bits.

    • This table summarizes the system response. Note that the nFAULT pin (available in both HW and SPI devices) will indicate a fault

    Best Regards,