BQ2060SS Datasheet, PDF (13/59 Pages) Texas Instruments – SBS V1.1-COMPLIANT GAS GAUGE IC

bq2060
www.ti.com
SLUS035E – JANUARY 2000 – REVISED OCTOBER 2005
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 bq2060 makes midrange corrections
as shown in Table 5.
Voltage()
Table 5. Midrange Corrections
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() set to 75%
RelativeStateOfCharge() set to 75%
RelativeStateOfCharge() set to 50%
RelativeStateOfCharge() set to 50%
RelativeStateOfCharge() set to 25%
RelativeStateOfCharge() set to 25%
Charge Control
Charging Voltage and Current Broadcasts
The bq2060 supports SBS charge control by broadcasting the ChargingCurrent() and ChargingVoltage() to the
Smart Charger address. The bq2060 broadcasts the requests every 10 s. The bq2060 updates the values used
the charging current and voltage broadcasts based on the battery’s state of charge, voltage, and temperature.
The fast-charge rate is programmed in Fast-Charging Current EE 0x1a - 0x1b while the charge voltage is
programmed in Charging Voltage EE 0x0a-0x0b.
The bq2060 internal charge control is compatible with popular rechargeable chemistries. The primary
charge-termination techniques include a change in temperature over a change in time (∆T/∆t) and current taper,
for nickel-based and Li-ion chemistries, respectively. The bq2060 also provides pre-charge qualification and a
number of safety charge suspensions based on current, voltage, temperature, and state of charge.
Alarm Broadcasts to Smart Charger and Host
If any of the bits 8–15 in BatteryStatus() is set, the bq2060 broadcasts an AlarmWarning() message to the Host
address. If any of the bits 12–15 in BatteryStatus() are set, the bq2060 also sends an AlarmWarning() message
to the Smart Charger address. The bq2060 repeats the AlarmWarning() message every 10 s until the bits are
cleared.
Pre-Charge Qualification
The bq2060 sets ChargingCurrent() to the pre-charge rate as programmed in Pre-Charge Current EE 0x1e-0x1f
under the following conditions:
• Voltage: The bq2060 requests the pre-charge charge rate when Voltage() drops below the EDV0 threshold
(compensated or fixed EDVs). Once requested, a pre-charge rate remains until Voltage() increases above
the EDVF threshold. The bq2060 also broadcasts the pre-charge value immediately after a device reset until
Voltage() is above the EDVF threshold. This threshold is programmed in EDVF/EDV0 EE 0x72-0x73.
• Temperature: The bq2060 requests the pre-charge rate when Temperature() is between 0°C and 5°C.
Temperature() must rise above 5°C before the bq2060 requests the fast-charge rate.
Charge Suspension
The bq2060 may temporarily suspend charge if it detects a charging fault. A charging fault includes the following
conditions.
• Overcurrent: An overcurrent condition exists when the bq2060 measures the charge current to be more than
the Overcurrent Margin above the ChargingCurrent(). Overcurrent Margin is programmed in EE 0x49. On
detecting an overcurrent condition, the bq2060 sets the ChargingCurrent() to zero and sets the
TERMINATE_CHARGE_ALARM bit in Battery Status(). The overcurrent condition and TERMINATE_
CHARGE_ALARM are cleared when the measured current drops below the ChargingCurrent plus the
Overcurrent Margin.
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