BQ2083-V1P3 Datasheet, PDF (14/56 Pages) Texas Instruments – SBS-COMPLIANT GAS GAUGE IC FOR USE WITH THE bq29311

bq2083-V1P3
SLVS508 − OCTOBER 2003
www.ti.com
Midrange Capacity Corrections
The bq2083−V1P3 applies midrange capacity corrections when the VCOR bit is set in Gauge Configuration DF 0x29.
The bq2083−V1P3 adjusts RM to the associated percentage at three different voltage levels: VOC25, VOC50, and
VOC75. The VOC values represent the open circuit battery voltage at which RM corresponds to the associated for
each threshold.
For the midrange corrections to occur, the temperature must be in the range of 19°C to 31°C inclusive and the
Current( ) and AverageCurrent( ) must both be between −64 mA and 0. The bq2083−V1P3 makes midrange
corrections as shown in Table 5. For a correction to occur, the bq2083−V1P3 must detect the need for correction twice
during subsequent 20-s intervals. With the VCOR bit set, the bq2083−V1P3 makes midrange corrections whenever
conditions permit. If the OTVC bit in Gauge Configuration DF 0x29 is set and VCOR = 0, the bq2083−V1P3 makes
a single attempt of mid-range correction immediately after device reset and does not require a second validation.
Table 5. Midrange Corrections
Voltage( )
CONDITION
≥ VOC75 and RelativeStateOfCharge( ) ≤ 63%
< VOC75 and RelativeStateOfCharge( ) ≥ 87%
≥VOC50 and RelativeStateOfCharge( ) ≤ 38%
<VOC50 and RelativeStateOfCharge( ) ≥ 62%
≥ VOC25 and RelativeStateOfCharge( ) ≤ 13%
< VOC25 and RelativeStateOfCharge( ) ≥ 37%
RESULT
RelativeStateOfCharge()→75%
RelativeStateOfCharge()→75%
RelativeStateOfCharge()→50%
RelativeStateOfCharge()→50%
RelativeStateOfCharge()→25%
RelativeStateOfCharge()→25%
Charge Control
Charging Voltage and Current Broadcasts
The bq2083−V1P3 supports SBS charge control by broadcasting the ChargingCurrent( ) and ChargingVoltage( ) to
the Smart Charger address. The bq2083−V1P3 broadcasts the requests every 50 seconds. The bq2083−V1P3
updates the values used in the charging current and voltage broadcasts based on the battery’s state of charge,
voltage, and temperature. The charge voltage is programmed in Charging Voltage DF 0x039-0x3a. The charge
current may take any of four different values: Fast Charging Current DF (0x3d–0x3c), Maintenance Charging Current
(DF 0x3f), Precharge Current (0x41), or 0. The charge current depends on charge state and operating conditions.
The bq2083−V1P3 internal charge control is compatible with the constant current/constant voltage profile for Li-Ion.
The bq2083−V1P3 detects primary charge termination on the basis of the tapering charge current during the
constant-voltage phase.
Alarm Broadcasts to Smart Charger and Host
If any of the bits 8−15 in BatteryStatus( ) are set, the bq2083−V1P3 broadcasts an AlarmWarning( ) message to the
Host address. If any of the bits 12−15 in BatteryStatus( ) are set, the bq2083−V1P3 also sends an AlarmWarning( )
message to the Smart Charger address. The bq2083−V1P3 repeats the AlarmWarning( ) messages every 10
seconds until the alarm bits are cleared.
Precharge Qualification
The bq2083−V1P3 sets ChargingCurrent( ) to the precharge rate as programmed in Precharge Current DF 0x41
under the following conditions:
D Voltage: The bq2083−V1P3 requests the precharge charge rate when Voltage( ) drops below the precharge
threshold or when the EDV0 threshold is detected. Once requested, a precharge rate remains until Voltage( )
increases above the precharge threshold and the EDV0 condition does not exist. The precharge threshold is
programmed in Precharge Voltage DF 0x3b−0x3c.
D Temperature: The bq2083−V1P3 requests the precharge rate when Temperature( ) is between 0°C and the
precharge threshold programmed in Precharge Temp 0x43. Temperature( ) must be 3°C higher than Precharge
Temp to allow the fast-charge rate.
NOTE:
If Current() falls below the mA value programmed in Charge Detect Current (DF 0xe9, 0xea) then the pre-charge FET
(if enabled) is turned off to reduce power consumption.
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