DRV8714-Q1: use one DRV8714 to drive three motor

Elec Cheng

Part Number: DRV8714-Q1

Hi Expert,

I see that one DRV8714 can drive three motor mentioned in below post. I have several question about this usage.

Can motor1 and motor 2 run at the same time?
If motor2 is free running and now I want to drive motor 1 or 3, is there any current flow conflict in the common half-bridge? I suppose it’s related with “make sure that the appropriate bridges are in Hi Z state when needed”. But I don’t figure out the details and how to apply the scheme properly

https://e2e.ti.com/support/motor-drivers-group/motor-drivers---internal/f/motor-drivers---internal-forum/1053061/drv8714-q1-motor-connection?tisearch=e2e-sitesearch&keymatch=drv8714%203%20motor

Thanks.

BR,

Elec Cheng

over 2 years ago

0 Jacob Thompson over 2 years ago

TI__Mastermind 23431 points

Hey Elec,

Our automotive driver expert is out today and will get back to you within 1 more business day, thanks!

Regards,

Jacob

0 Brian Dang over 2 years ago

Genius 5040 points

Hi Elec,

The DRV871x provides from 4 or 8 half-bridge (called 4 or 8 channels) and they are independence channels. To drive 3 motors you need the 8718 as each brushed motor needs 2 channels and so 3 x 2 = 6 which means you cannot use 8714. For brushless motor then each motor needs 3 channels for driving 6 FETs for 3-phase brushless DC motor. Since they are independence 8 channels, you can independently control each motor as you wish.

Regards,

Brian

0 Elec Cheng over 2 years ago in reply to Brian Dang

TI__Expert 7055 points

Hi Brian,

You can check the e2e post that I attach at the beginning. It says DRV8714-Q1 can drive three motor with below configuration. I just want to understand more details about how it works and how to perform with DRV8714-Q1. May you help check internally and provide those info? Thanks.

BR,

Elec Cheng

0 Shinya Morita over 2 years ago in reply to Elec Cheng

TI__Mastermind 44855 points

Hi Elec,

I will review your question and feedback to you within 24hours.

regards

Shinya Morita

0 Brian Dang over 2 years ago in reply to Elec Cheng

Genius 5040 points

Elec Cheng said:
You can check the e2e post that I attach at the beginning. It says DRV8714-Q1 can drive three motor with below configuration. I just want to understand more details about how it works and how to perform with DRV8714-Q1. May you help check internally and provide those info? Thanks.

Hi Elec,

I clicked on this link https://e2e.ti.com/support/motor-drivers-group/motor-drivers---internal/f/motor-drivers---internal-forum/1053061/drv8714-q1-motor-connection?tisearch=e2e-sitesearch&keymatch=drv8714%203%20motor

and I got "Page Not Found" error message.

Anyway it depends on how you want to drive the motors (brushed type in this case): one direction only, or full forward and reverse control? If the motors only run one direction and open-loop control, then the wiring diagram you posted seems to work, but if the motors are under speed or torque control, then each motor need a full H-bridge or 2 half-bridge, then the diagram doesn't work for you. Please let us know how do you want to control the motors: open-loop one direction, or closed-loop controlled, or opened-loop two directions.

Brian

0 Shinya Morita over 2 years ago in reply to Brian Dang

TI__Mastermind 44855 points

Hi Brian,

Thank you for your response to Elec,

Hi Elec,

Please do not attach internal post information here.

regards

Shinya Morita

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DRV8714-Q1: use one DRV8714 to drive three motor