DRV11873 Damage

Adesh Jagtap

Other Parts Discussed in Thread: DRV11873

Hello,

I am working on BLDC motor circuitry using this driver DRV11873. There is on problem associated with this driver which I faced multiple times. I am operating this IC at 15V and 100% PWM. If I turn ON and OFF my supply two- three times, IC is getting damaged. Damage means U/V/W and ground is getting shorted. And sometimes U/V/W and Vcc are getting shorted. this indicates that MOSFET in half bridges are getting damaged, right? Can you explain me why is this happening?

over 9 years ago

0 Rick Duncan over 9 years ago

TI__Guru** 114905 points

Hi Adesh,

Our experts have been notified and should reply soon.

When turning your power supply on and off, are the absolute maximum and minimum voltages violated?

0 Janet Yi over 9 years ago

TI__Intellectual 770 points

Motor is inductive load, voltage would recirculate back to VCC. VCC would be more than 15V.

Would please you take a look on scope for VCC voltage when that happen? Thank you.

We will try it to our side. But it will take sometime.

Thanks,

Janet Yi

0 Adesh Jagtap over 9 years ago in reply to Janet Yi

Intellectual 320 points

If that is the case then it should happen with any supply voltage, right?
but if I try the same when supply voltage is 10V then it does not happen.

0 Adesh Jagtap over 9 years ago in reply to Janet Yi

Intellectual 320 points

What are you trying by your side? I didn't get what do you mean.

0 Janet Yi over 9 years ago in reply to Adesh Jagtap

TI__Intellectual 770 points

Lower VCC, and recirculate voltage is lower. I will try the same experiment (on/off test), but it will take some time.
Would please you send us VCC and phases scope snapshots when device got damaged during on / off testing? Thank you.

Thanks again,
Janet

0 Adesh Jagtap over 9 years ago in reply to Janet Yi

Intellectual 320 points

Actually, I can't take a risk to damage more ICs because I am out of stock now. But I observed at lower VCC that there are some sudden voltage rises above voltage supplied in startup of motor. Then to avoid these sudden rises I connected capacitors at Vcc. Now there are not sudden rises at starting.
But I have observed other problems too with this IC one of which is today while testing there were two shorts
VCC and ground &
V5 and ground
I am not getting why these happened?
Can you please help me in this front?

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DRV11873 Damage