BQ40Z50: bq40z50r1

Arkadi shap

Intellectual 660 points

Part Number: BQ40Z50

Hi,

I want to use bq40z50r1.

The battery Charge current is 100mA, and the discharge current to the load is 100uA.

I want to use the Coulomb Counter to find the SOC of the battery. The questions are:

1- What is the current resolution? can 100uA and 100mA be sensed?

2- In this case what is the value of the sense resistor should be?

3- What is the error of the sensing (in the above case)?

I read the datasheet a few times, and i cant find the answers to these questions...

Thank you very much!

over 6 years ago

0 Batt over 6 years ago

TI__Mastermind 42535 points

Sorry, your currents are way below what we can sense. Unfortunately we won't be able to support such current levels. We need a minimum of 40mA to gauge correctly.

0 Arkadi shap over 6 years ago in reply to Batt

Intellectual 660 points

Thank you very much for your answer!
Is there any other TI coloumb counter that can sense such a low currents?

Regards,
Arkadi

0 Arkadi shap over 6 years ago in reply to Arkadi shap

Intellectual 660 points

by the way, i the data sheet should define the minimum voltage on the sense resistor.
what is the minimum voltage for the sense pins? (40mA on what resistor)

Thatks,
Arkadi

0 Batt over 6 years ago in reply to Arkadi shap

TI__Mastermind 42535 points

sorry, I'm not sure TI has coulomb counters that can measure that low current. The Rsns dynamic range is +/- 200mV. You are advised to choose between a 1 - 3mOhm sense resistor.

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BQ40Z50: bq40z50r1