DRV8834: An issue with the external DAC on the xVREF pin of the chip

Cherry Zhou

Part Number: DRV8834
Other Parts Discussed in Thread: DAC60502,

Hi team,

Is it possible to dynamically adjust the current maximum of the 8834 by connecting the two analogue outputs of the DAC60502 chip directly to the AVREF and BVREF pins of the DRV8834? If so, are there any good suggestions for use?

Could you help resolve this case? Thanks.

Best Regards,

Cherry

over 2 years ago

0 Wang5577 over 2 years ago

TI__Guru 56650 points

Hello, Cherry,

The AVREF and BREF can be changed during the fly. I would add a small capacitor between DAC60502 and AVREF and BVREF to filter out the noise.

Do you see any issue with this setup?

Regards,

Wang Li

0 Cherry Zhou over 2 years ago in reply to Wang5577

TI__Mastermind 22235 points

Hi Wang Li,

1. Can the input voltage of xVREF be adjusted freely during the 8834 power-up? Do we need to do something with the 8834 before adjusting?

Wang5577 said:
The AVREF and BREF can be changed during the fly.

May I know what do you mean by 'during the fly'?

3. What is the recommended empirical value for the decoupling capacitor?

Thanks and Best Regards,

Cherry

0 Wang5577 over 2 years ago in reply to Cherry Zhou

TI__Guru 56650 points

Cherry,

1. "Change during the fly or on the fly" means that parameter can be changed during a normal operating.

2. I would start from 1nF decoupling capacitor and check the xVREF pin voltage to make sure no strong noise on xVREF.

Regards,

Wang

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DRV8834: An issue with the external DAC on the xVREF pin of the chip