DRV8308: Please tell me how to control the rotation of motor.

tatsuro tokugawa

Part Number: DRV8308

Hi team,

I am using DRV8308 to control a brushless motor.
The rotation of the motor is controlled by "Clock Frequency Mode".
I am inputting a 150Hz square wave to CLKIN, but the rotation of the motor is not so stable.
In such a case, should the MPU adjust the rotation by referring to the FGOUT(HALL_U)?
Please tell me how to do that.

Best regards,

over 1 year ago

0 Vishnu Balaraj over 1 year ago

TI__Mastermind 24405 points

Hi Tatsuro

Thanks for posting your question in MD forum. I will get back to you shortly!

Vishnu

0 Vishnu Balaraj over 1 year ago

TI__Mastermind 24405 points

Hi Tatsuro.

DRV8308 has an in-build speed differentiator which compares the CLKIN to FG and adjusts the motor speed according to the error. What is the Frequency of FG at 150 hz CLKIN? Did you try tuning the SPDGAIN? Can you refer to section 3.2 in the User's guide on tuning the speed loop?

Regards,

Vishnu

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DRV8308: Please tell me how to control the rotation of motor.