BQ76952: Sampling sinusoidal current is not accurate

zehu chi

Part Number: BQ76952

Tool/software:

Hi TI engineer:

We use this chip to collect current, and find that when the current is a sine wave, the sampling current will not be accurate, we use the instantaneous current as the sampling current, may I ask if there is any good way to improve this problem?

Would it improve if we used average current?

Looking forward to your reply! thank you!

11 months ago

0 Alexis_H 11 months ago

TI__Mastermind 18035 points

Hello Zehu,

Yes, using average current would be more accurate.

Best Regards,
Alexis

0 zehu chi 11 months ago in reply to Alexis_H

Intellectual 445 points

Hi Alexis，

Thank you for your reply.

If we want to avoid sampling inaccuracies due to sinusoidal currents, should we use a CC1 or CC2 or CC3 filter to sample the current?

Regards,

Zehu

0 Alexis_H 11 months ago in reply to zehu chi

TI__Mastermind 18035 points

Hello Zehu,

Most likely CC1 would be enough for what you're looking for, however, it may depend on your frequency. Section 4.3 Coulomb Counter and Digital Filters in the BQ76952 Technical Reference Manual (Rev. B) may provide more information to help you decide.

Best Regards,
Alexis

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BQ76952: Sampling sinusoidal current is not accurate