BQ2084-V133 Datasheet, PDF (52/64 Pages) Texas Instruments – SBS v1.1-COMPLIANT GAS GAUGE FOR USE WITH THE bq29312

bq2084-V133
SLUS640A – JUNE 2005 – REVISED JUNE 2005
www.ti.com
CC offset
CC offset (DF 0xd2-0xd3), contains the offset for the coulomb counter. It is automatically updated when the
pack has met the conditions for sleep, before it enters sleep mode.
DSC offset
DSC offset (DF 0xd4), contains the offset for the pack ground reference. It is automatically updated when the
pack has met the conditions for sleep, before it enters sleep mode.
ADC offset
ADC offset (DF 0xd5), contains the offset for the a/d converter. It is automatically updated when the pack has
met the conditions for sleep, before it enters sleep mode.
Digital Filter
The desired digital filter threshold, VDF (V), is set by the value stored in Digital Filter (DF 0x2c).
Digital Filter = VDF ÷ 290 nV
CELL AND PACK CHARACTERISTICS
Battery Pack Capacity and Voltage
Pack capacity in mAh units is stored in Design Capacity (DF 0x32-0x33). In mAh mode, the bq2084-V133 copies
Design Capacity to DesignCapacity(). In mWh mode, the bq2084-V133 multiplies Design Capacity by Design
Voltage (DF 0x04-0x05) to calculate DesignCapacity() scaled to 10 mWh. Design Voltage is stored in mV.
The initial value for Full Charge Capacity, in mAh, is stored in DF 0x36-0x37. Full Charge Capacity is modified
over the course of pack usage to reflect cell aging under the particular use conditions. The bq2084-V133 updates
Full Charge Capacity in mAh after a capacity learning cycle.
Remaining Time Alarm and Capacity Alarm
Remaining Time Alarm (DF 0x02-0x03) sets the alarm thresholds used in the SMBus command codes 0x01 and
0x02, respectively. Remaining Time Alarm is stored in minutes and Remaining Capacity Alarm in units of mAh or
10 mWh, depending on the BatteryMode() setting.
Cycle Count Initialization
Cycle Count (DF 0x0c-0x0d) stores the initial value for the CycleCount() function. It should be programmed to
0x0000.
Cycle Count Threshold
Cycle Count Threshold (DF 0x37-0x38) sets the number of mAh that must be removed from the battery to
increment CycleCount(). Cycle Count threshold is a 16-bit value stored in mAh.
Charge Efficiency
The bq2084-V133 applies the efficiency factor, EFF%, to all charge added to the battery. EFF% is encoded in
Charge Efficiency (DF 0x54) according to the following equation:
Charge Efficiency = (EFF% w 2.56-1)
PACK OPTIONS
Pack Configuration
Pack Configuration (DF 0x28) contains bit-programmable features.
b7
b6
b5
b4
b3
b2
b1
b0
DMODE
LED1
LED0
HPE
CPE
SM
CC1
CC0
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