• State
  • Locked Locked
  • Replies 1 reply
  • Subscribers 28 subscribers
  • Views 1085 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

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.

Burnt DRV8818

Pierce Nichols
Prodigy 20 points
Other Parts Discussed in Thread: DRV8818

I have designed a stepper driver around the DRV8818 (see attached schematic). When I plug it in and power it up with 12V on the motor voltage and , it powers up with holding current and promptly fails completely, on one occasion with visible smoke. I've clearly done something terribly wrong, but I can't figure out what it is. Anyone have some clues for the clueless?

  • 0
    TI__Mastermind 26065 points

    Hi Pierce

    I can't find any VM caps like a 0.1uF + 100uF on VM line. Is it true in real board?

    Without the VM caps, the VM voltage will be quite unstable when the current is ON. It is possible that all the functions including current limit and regulation working abnormally without VM caps. Burning is also possible when the motor's phase resistor is too small.

    Those caps should be placed to VM pin and GND plane closely with wide tracks. The total cap value should be >100uF usually, depends on your current rating.  

    Please varify this with a >= 100uF VM cap soldered near VMx pins to GND pin (or plane).

    Thanks,

    Wilson Zuo