• State
  • Replies 5 replies
  • Subscribers 29 subscribers
  • Views 51 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

Original question:

DRV8316: Running the DRV8316 with a sensorless sinusoidal input

DRV8316: MCF8316 min speed

Asaf Pipman
Prodigy 70 points
Part Number: DRV8316
Other Parts Discussed in Thread: DRV10970

Tool/software:

Hi!

I'd like to know what is the min speed the MCF8316 is able to rotate a BLDC motor, in a smooth motion.
My use case is:
1. minimal load (a few hundred grams)

2. I must have a smooth rotation throughout the movement.

3. no load change will occur throughout the motion.

I'm aiming at a lowest RPM of 0.2, and my current motor has 21 pole pairs

Should this be possible?

Thanks!

  • 0
    TI__Intellectual 2491 points

    Hi Asaf,

    Thanks for your question, please give me a day or two to get back.

    Regards,
    Sachin S

  • 0 in reply to Sachin S
    TI__Intellectual 2491 points

    Hello Asaf,

    For 0.2RPM, MCF8316 may not be ideal, since the BEMF is very low at low speeds. Would you willing to evaluate our MCTx portfolio?

    Thanks and regards,
    Sachin S

  • 0 in reply to Sachin S
    Prodigy 70 points

    Hi Sachin, thank you for your answer.

    We've decided on a sinusoidal drive (and motor) for the following reasons:
    1. We are aiming at minimizing torque ripple since we need the rotation to be exceptionally smooth.

    2. We're using a high resolution rotary encoder for position feedback, and so as we understood it, BEMF may not be so relevant. Please correct me if I'm wrong here.

    Using the MCF8316, and a high resolution encoder, should I be able to run my motor at my intended speed?

  • 0 in reply to Asaf Pipman
    TI__Intellectual 2491 points

    Hello Asaf,

    Understood your requirement. The MCF8316C is a sensor-less driver. You could look at the DRV10970. It is a sensored sine/trap device.

    Thanks and regards,

    Sachin S 

  • 0 in reply to Sachin S
    Prodigy 70 points

    Hi Sachin!

    Thanks for your answer!
    Reading through the DRV10970, it seems like it is designed for either differential or single-ended Hall sensor based applications. My application scenario does not include hall sensors, but does include a QEP encoder. 

    Is there a similar device working with an encoder, and/or a device implementing an FOC drive?

    Additionally, could you tell me a bit about the differences between the DRV10xxx family and the DRV8xxx family?