BQ2083-V1P3 Datasheet, PDF (18/56 Pages) Texas Instruments – SBS-COMPLIANT GAS GAUGE IC FOR USE WITH THE bq29311

bq2083-V1P3
SLVS508 − OCTOBER 2003
www.ti.com
Li-Ion Protector Control
The bq2083−V1P3 provides protection for Li-Ion batteries, as shown in Table 10. The bq2083−V1P3 uses the
bq29311 to measure and report individual series cell voltages. The bq2083−V1P3 determines if a voltage protection
condition has been breached and turns off the respective control FET via I²C communication to the bq29311. It is
recommended that the bq2083−V1P3 protection control be validated by two successive measurements by setting
VOD=1 in Misc Configuration.
The bq29311 can detect and protect the load from an overcurrent (OC) or short circuit (SC). The bq29311 alerts the
bq2083−V1P3 with the XALERT output when ever an overcurrent or short circuit threshold is breached in either the
charge or discharge directions.
The bq2083−V1P3 asserts CVOV and instructs the bq29311 to turn off the charge FET if an Overvoltage or
Overtemperature condition exists, or if AverageCurrent( ) ≥ Fast-Charging Current + Over Current Margin
(Prolonged Overcurrent condition in Table 6). The bq2083−V1P3 does not turn off the charge FET if there is a
discharge current > 50 mA. The bq2083−V1P3 instructs the bq29311 to turn on the charge FET when Overvoltage
and Overtemperature conditions no longer exist, and AverageCurrent( ) < 256 mA (if Prolonged Overcurrent
generated the fault condition).
The bq2083−V1P3 asserts CVUV and instructs the bq29311 to turn off the discharge FET if an Overdischarged
condition exists, or if AverageCurrent( ) ≤ − overload current (Overload). The bq2083−V1P3 does not turn off the
discharge FET if there is a charge current ≥ 50 mA. The bq2083−V1P3 instructs the bq29311 to turn on the discharge
FET when the Overdischarged condition no longer exists and AverageCurrent( ) > −256 mA (if Overload generated
the fault condition).
Table 10. bq2083−V1P3 to bq29311 Interface (FET Protection Control)
Battery State (Table 6)
CVOV = 1: Prolonged Overcurrent, Overvoltage, Overtemperature
CVOV = CVUV = 0
CVUV = 1: Overload, Overdischarged
(1) _{State determined by bq29311}
(2) _{On if there is a discharge current ≥ 50 mA}
(3) _{On if there is a charge current ≥50 mA.}
DISCHARGING FET
Normal (see Note 1)
Normal (see Note 1)
Off (see Note 3)
CHARGING FET
Off (see Note 2)
Normal (see Note 1)
Normal (see Note 1)
Table 11. Stand-Alone bq29311 Protection Control
MODE
CONDITION
Over Load
AFE Over Curr Dsg (DF 0xb2) is breached for Over Curr Delay (DF 0xb4)
Over Current
AFE Over Curr Chg (DF 0x0b3) is breached for Over Curr Delay (DF 0xb4)
Short Circuit, Discharge AFE Short Circ Thresh (DF 0xb6) is breached for AFE Short Circuit Delay (DF
0xb7, lower nibble)
Short Circuit, Charge
AFE Short Circ Thresh (DF 0xb6) is breached for AFE Short Circuit Delay (DF
0xb7, upper nibble)
(1) _{Clear is detected and controlled by the bq2083−V1P3.}
CLEAR (see Note 1)
AverageCurrent() = 0 mA
AverageCurrent() = 0 mA
AverageCurrent() = 0 mA
AverageCurrent() = 0 mA
SAFE Output
The SAFE output of the bq2083−V1P3 provides an additional level of safety control. The active low safety output
can blow a fuse or control another switch on the basis of temperature, pack-voltage cell-voltage, or an integrity check
of the AFE registers.
The SAFE output is driven low in any of the following 4 conditions and if the SAFE output activates, the bq2083−V1P3
sets the SOV bit in pack status. SOV remains set until the bq2083−V1P3 is reset. The SAFE output can be pulled
high (cleared) by a POR of the bq2083−V1P3 only.
SAFE activation conditions:
D When CVOV = 1 AND after a minimum of 1s Voltage() > Safety Over Voltage (DF 0x68 and 0x69), or
D When CVOV = 1 AND after a minimum of 1s the Temperature() > Safety Temperature (DF 0x6a and 0x6b)
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