• State
  • Locked Locked
  • Replies 1 reply
  • Subscribers 28 subscribers
  • Views 336 views
  • Users 0 members are here
Support feedback
Options
Options
Related

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.

Question about using DRV8312 motor driver

dennis sinitsky
Prodigy 30 points
Other Parts Discussed in Thread: DRV8312

Dear TI expert,

I hope this is the right forum for my question. If not, feel free to move it; I did not find dedicated motor driver forum.

I am using DRV8312 motor driver chip in my setup. I am measuring transient on nodes OUT_A and GND_A, which are output of A-phase driver to the motor and Rsense voltage of phase A. The transient I see (for Vbat=24V) is -15V for OUT_A and -1.35V for GND_A. The -1.35V corresponds to 135A current going into the motor. This is huge! And -15V on OUT_A is very large negative spike. Is that right? Or my setup has some problem? 

You can see image below: yellow color is OUT_A and green color is GND_A.

Thank you

Dennis

  • 0
    TI__Mastermind 26065 points

    Hi Dennis,

    We can't see the attachments here. 

    What is real current when you see the -15V and -1.35V? DRV8312 is not designed for such high current even the peaks.

    Normally there will be short time peak minus voltage on these pins but not that high. The peak minus voltage is partly due to the inductance free wheeling and layout parasitic inductance. It is also important to get the real minus voltage with correct measurements setup and reference GND point.

    Please give the circuit of DRV8312 and layout if possible. Also please attached the waveform of Phase Current, OUT_A, GND_A voltage better in one screen, zoom the minus peak votage in detail.

    Best regards,