BQ2040 Datasheet, PDF (15/33 Pages) Texas Instruments – Gas Gauge IC With SMBus Interface

bq2040
Accuracy: ± 1% of the DesignCapacity after cali-
bration
MaxError() (0x0c)
Returns the expected margin of error (%) in the state of
charge calculation.
Output: unsigned integer. Returns the percent un-
certainty for selected information.
Units: %
Range: 0 to 100%
RelativeStateOfCharge() (0x0d)
This read-only word returns the predicted remaining
battery capacity expressed as a percentage of FullChar-
geCapacity (%). RelativeStateOfCharge is only
valid for battery capacities more than 1504mAh
and less than 10,400mAh.
Output: unsigned integer. Returns the percent of re-
maining capacity.
Units: %
Range: 0 to 100%
Granularity: 1%
Accuracy: ±MaxError after circuit and capacity
calibration
AbsoluteStateOfCharge() (0x0e)
This read-only word returns the predicted remaining
battery capacity expressed as a percentage of DesignCa-
pacity (%). Note that AbsoluteStateOfCharge can return
values greater than 100%. Absolute StateOfCharge
is only valid for battery capacities more than
1504mAh and less than 10,400mAh.
Output: unsigned integer. Returns the percent of
remaining capacity.
Units: %
Range: 0 to 65,535%
Granularity: 1%
Accuracy: ±MaxError after circuit and capacity
calibration
RemainingCapacity() (0x0f)
This read-only word returns the predicted remaining
battery capacity. The RemainingCapacity value is ex-
pressed in mAh.
Output: unsigned integer. Returns the estimated re-
maining capacity in mAh.
Units: mAh
Range: 0 to 65,535mAh
Granularity: 0.2% of DesignCapacity or better
Accuracy: ±MaxError ∗ FCC after circuit and ca-
pacity calibration
FullChargeCapacity() (0x10)
This read-only word returns the predicted pack capacity
when it is fully charged. FullChargeCapacity defaults
to the value programmed in the external EEPROM until
a new pack capacity is learned. The new FCC is stored
to EEPROM within 400ms of a valid charge after a
qualified discharge.
Output: unsigned integer. Returns the estimated full
charge capacity in mAh.
Units: mAh
Range: 0 to 65,535mAh
Granularity: 0.2% of DesignCapacity or better
Accuracy: ±MaxError ∗ FCC after circuit and ca-
pacity calibration
RunTimeToEmpty() (0x11)
This read-only word returns the predicted remaining
battery life at the present rate of discharge (minutes).
The RunTimeToEmpty value is calculated based on
Current.
Output: unsigned integer. Returns the minutes of
operation left.
Units: minutes
Range: 0 to 65,534min
Granularity: 2min or better
Invalid data indication: 65,535 indicates battery is
not being discharged.
AverageTimeToEmpty() (0x12)
This read-only word returns the predicted remaining
battery life at the present average discharge rate (min-
utes). The AverageTimeToEmpty is calculated based on
AverageCurrent.
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