BQ2060SS Datasheet, PDF (29/59 Pages) Texas Instruments – SBS V1.1-COMPLIANT GAS GAUGE IC

bq2060
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SLUS035E – JANUARY 2000 – REVISED OCTOBER 2005
numeric indication of remaining charge or energy given by the Absolute or Relative
StateOfCharge() functions and may be in a better form for use by power management systems.
SMBus PROTOCOL ReadWord
OUTPUT Unsigned integer—remaining charge in mAh or 10mWh.
Units
Range
Granularity
Accuracy
BATTERY MODES
CAPACITY_MODE
bit = 0
CAPACITY_MODE
bit = 1
mAh
10 mWh
0 to 65,535 mAh
0 to 65,535 10 mWh
mAh
10 mWh
–0, +MaxError() * FullChargeCapacity()
FullChargeCapacity() (0x10); [0x10]
DESCRIPTION
Returns the predicted pack capacity when it is fully charged. The FullChargeCapacity() value is
expressed in either current (mAh at a C/5 discharge rate) or power 10 mWh at a P/5 discharge
rate) depending on the setting of the BatteryMode()’s CAPACITY_MODE bit.
PURPOSE
The FullChargeCapacity() function provides the user with a means of understanding the tank size of
their battery. This information, along with information about the original capacity of the battery, can
be presented to the user as an indication of battery wear.
SMBus PROTOCOL ReadWord
OUTPUT Unsigned integer—estimated full-charge capacity in mAh or 10mWh.
Units
Range
Granularity
Accuracy
BATTERY MODES
CAPACITY_MODE
bit = 0
CAPACITY_MODE
bit = 1
mAh
10 mWh
0 to 65,535 mAh
0 to 65,535 10 mWh
mAh
10 mWh
–0, +MaxError() * FullChargeCapacity()
RunTimeToEmpty() (0x11); [0x11]
DESCRIPTION
Returns the predicted remaining battery life at the present rate of discharge (minutes). The
RunTimeToEmpty() value is calculated based on either current or power depending on the setting
of the BatteryMode()’s CAPACITY_ MODE bit.
PURPOSE
The RunTimeToEmpty() provides the power management system with information about the
relative gain or loss in remaining battery life in response to a change in power policy. This
information is NOT the same as the AverageTimeToEmpty(), which is not suitable to determine the
effects that result from a change in power policy.
SMBus PROTOCOL ReadWord
OUTPUT
Unsigned integer—minutes of operation left.
Units: minutes
Range: 0 to 65,534 min
Granularity: 2 min or better
Accuracy: –0, +MaxError() x FullChargeCapacity() / Current()
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