DRV8885 chopping current caiculation

NAOKI AOYAMA

Guru 11215 points

Other Parts Discussed in Thread: DRV8885

Hello,

Our customer uses the DRV8885, control RREF with a DAC.

He calculates the chopping current by equation (2) on the datasheet P18.

The answer is 890mA, at the RREF is 20kOhm.

It is mentioned the current is 600mA on the datasheet.

Is the datasheet correct?

Regards,

Naoki Aoyama

over 9 years ago

0 Nicholas Oborny over 9 years ago

TI__Mastermind 21320 points

Hi Naoki,

I reached the same answer (891 mA). I will investigate with the system engineer, but they are out of office until Jan 4th so a response may be delayed.

0 Wilson Zuo over 9 years ago in reply to Nicholas Oborny

TI__Mastermind 26065 points

Hi Naoki,

Just got similar question and checked with system that this should be a typo of datasheet. The 20k used in the example should be 30k, then 600mA is matched. The equation is correct.

Best regards,

0 NAOKI AOYAMA over 9 years ago in reply to Wilson Zuo

Guru 11215 points

Hi Wilson,

Thank you for your reply.
I will feedback our customer this information.

Thanks,
Naoki Aoyama

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DRV8885 chopping current caiculation