DRV8316: Regarding current sense amplifier offset correction

Daisuke Higa

Expert 2940 points

Part Number: DRV8316

Hi support team.

My customer has asked me regarding current sense amplifier offset correction.

・Is I_offset taken into account in the following equations?

・Is it okay to understand that "ix_sensed" is a measured value of phase current?

Best Regards,

Higa

over 1 year ago

0 Aaron Barrera over 1 year ago

TI__Mastermind 25956 points

Hi Higa-san,

Is I_offset taken into account in the following equations?

Yes, any current induced offset is taken into account for these equations. These equations are used to resolve dynamic CSA offset issues in this revision of DRV8316 silicon.

Is it okay to understand that "ix_sensed" is a measured value of phase current?

"ix_sensed" means the value calculated from SOA/SOB/SOC when you use the normal equation to calculate phase current:

Thanks,
Aaron

0 Daisuke Higa over 1 year ago in reply to Aaron Barrera

Expert 2940 points

Hi Aaron-san

Thank you for answering.

I understand the following:

Ix_sensed = IOUTx,

ix_sensed = (1 / ± GAIN) (SOX-VREF / 2)

(SOX includes offset voltage)

After measuring SOX voltage, the phase current is estimated by equations (5) to (7).

Is the above understanding correct?

Best Regards,

Higa

+1 Aaron Barrera over 1 year ago in reply to Daisuke Higa

TI__Mastermind 25956 points

Hi Higa-san,

Yes, your understanding is correct.

Thanks,
Aaron

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DRV8316: Regarding current sense amplifier offset correction