DRV8871: Continuous Current Rating

Rachel Harris

Part Number: DRV8871

Hi,

What is the continuous current provided by the DRV8871 motor driver? I understand that it's peak current is 3.6 A (I assume this is only for a few milliseconds) but I'm confused as to what the current output is under normal/recommended operating conditions or what the driver can sustain for longer periods of time. For reference, I would like to use the driver with a 10 W, 9 V motor and I'm trying to ensure that the driver can provide the necessary current to run the motor for extended periods of time. Any help would be appreciated.

Thanks,

Rachel

over 7 years ago

0 Rick Duncan over 7 years ago

TI__Guru** 114905 points

Hi Rachel,

What do you consider extended periods of time?
Does the motor continue to operate at 9W during this time?

Extended operation of the device depends primarily on the ambient temperature and the PCB 's ability to act as a heatsink.
Please consider evaluating the DRV8871EVM.

0 Rachel Harris over 7 years ago in reply to Rick Duncan

Prodigy 30 points

The motor will likely be running intermittently for a few seconds at a time (1-2 seconds) every few seconds. And yes, I believe it should still be operating at 9W during that time.

0 Rick Duncan over 7 years ago in reply to Rachel Harris

TI__Guru** 114905 points

Hi Rachel,

The device should operate with this condition with proper thermals.

0 Rachel Harris over 7 years ago in reply to Rick Duncan

Prodigy 30 points

Sorry, but to clarify, by 'operate with this condition', do you mean that it will operate at the specified peak current of 3.6 A? Also, what is a proper thermal? Is that like a heatsink?

0 Rick Duncan over 7 years ago in reply to Rachel Harris

TI__Guru** 114905 points

Hi Rachel,

I meant operate at your conditions of "The motor will likely be running intermittently for a few seconds at a time (1-2 seconds) every few seconds". The device should also be able to hit peaks of 3.6A but the time will be limited.

Since the ambient temperature and the PCB layout (ground plane area and copper weight) are unknown, it is difficult to predict operation beyond this.

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DRV8871: Continuous Current Rating