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DRV8353: DRV broken during high speed or sudden speed change operation

Gear Feng
Prodigy 30 points
Part Number: DRV8353

Tool/software:

DRV broken sometimes. Especially during the high speed operation or sudden speed change (without load).
It was a BLDC motor with encoder.

After the failure, one of the GL output 2.1V when not in operation. The termperature of the IC raises fast. I guess it triggered thermal or other fault and kept reseting.

I also tried different gain and IDRIVE setting. Non of them helped.
Gain = 20 and 40
450mA/900mA and 300mA/600mA
VDS = disabled

I also tried to add a snubber to the SHn close to the MOS output(100pF, 33R) and still broken.

Any suggestions?

  • 0
    TI__Mastermind 23306 points

    Hey Gear,

    1) How many devices were tested? and how many of them were damaged? Did you perform any ABA swap testing?

    2) Also could you perform impedance testing on the damaged vs good chip to see which pins might be shorted?

    3) Also I think the Idrive setting chosen is too high for the MOSFET in application.

    We expect 200ns VDS slew time for fast switching application and with 600mA you are turning off the MOSFEt in 23nS which is extremely fast and can cause ringing/abs max violation on gate and source nodes of the driver leading to damage. Did you capture GHx, SHx, waveforms of a few switching cycles to see the over/under shoot?

    Best,

    Akshay

  • 0 in reply to Akshay Rajeev Menon
    Prodigy 30 points

    Hi Aksay,
    Thank you for the reply.

    1. At least 12 devices were tested. With certain operation I believe all of them could be damaged. And yes I did ABA sawp and still broken.
    2. It is not easy for me to perform the impedance testing but the damage DRV is certain that at least one GL port is abnormal and sometimes the VGLS is abnormal.
    3. I've measured the Vgs. I don't think it is very fast. These are the waveform but not during the damaged phase.

    I believe the damage would be the ringing or other sudden spike that is over the max violation of the gate and source for the DRV (MOSFETs are fine).

    Any suggestions?

  • 0 in reply to Gear Feng
    TI__Mastermind 23306 points

    Hey Gear,

    I am talking about VDS not VGS voltage. VDS is a portion of VGS (during miller plateau).

    If your VGS response is 200ns then the VDS must be much shorter. The noise from large VDS swing is why you might be seeing the noise in the ,middle portion of the VGS rise.

    Please check this FAQ on IDrive selection.

     [FAQ] Selecting the Best IDRIVE setting and Why this is Essential 

    Best,

    Akshay