Clarification on nPM1300 Current Measurements

Hello,

I have a few questions regarding the nPM1300 current measurements:

  1. As far as I understand, there are two ways to trigger a current measurement:

    • By writing to the TASKIBATMEASURE register (mentioned only in the register documentation).
    • By enabling auto measurement through ADCIBATMEASEN and triggering a VBAT measurement using TASKVBATMEASURE.

    Could you confirm if this understanding is correct?

  2. Once a measurement is completed, I believe the current measurement results can be found in:

    • ADCVBAT2RESULTMSB
    • The VBAT2RESULTLSB field of the ADCGP1RESULTLSBS register.

    Is this correct?

  3. Regarding the conversion of measurements into a current value, the formula for this is not documented.
    Would the following formula be accurate?

    IBAT=(IBAT_ADC / 1023) × IFS_IBAT

    where:

    • IBAT_ADC is the ADC value derived from the above registers.
    • IFS_IBAT is the full-scale current for IBAT measurement.

    If this formula is incorrect, could you provide the correct one?

  4. I found documentation about the full-scale current (IFS_IBAT) in section 7.1.8 of the PS v1.1.
    Specifically, it seems dependent on the current flow direction returned in the bits `BCHARGERMODE` of register `ADCIBATMEASSTATUS`:

    • For a value of 01 (battery discharging), the full-scale current is calculated as: IFS_IBAT=(Weighted sum of registers BCHGISETDISCHARGEMSB and BCHGISETDISCHARGELSB) × 0.836
    • For a value of 11 (battery charging), the full-scale current is: IFS_IBAT=(Weighted sum of registers BCHGISETMSB and BCHGISETLSB) × 1.25

    I have a few questions here:

    • Are 01 and 11 binary values, and are these the only two possible values for BCHARGERMODE? I am currently reading 00.
    • When referring to the "weighted sum" of the respective charge and discharge current settings registers, does this include only the 10-bit value, or is there additional processing involved?

The voltage measurements are well-documented, but I found the current measurement documentation lacking.

Thank you for your assistance!

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