BQ2057CTSTRG4 Datasheet, PDF (1/30 Pages) Texas Instruments – ADVANCED LINEAR CHARGE MANAGEMENT IC FOR SINGLE-AND TWO-CELL LITHIUM-ION AND LITHIUM-POLYMER

bq2057, bq2057C
bq2057T, bq2057W
SLUS025F − MAY 2001 − REVISED JULY 2002
ADVANCED LINEAR CHARGE MANAGEMENT IC
FOR SINGLEĆ AND TWOĆCELL LITHIUMĆION AND LITHIUMĆPOLYMER
FEATURES
D Ideal for Single (4.1 V or 4.2 V) and Dual-Cell
(8.2 V or 8.4 V) Li-Ion or Li-Pol Packs
D Requires Small Number of External
Components
D 0.3 V Dropout Voltage for Minimizing Heat
Dissipation
D Better Than ±1% Voltage Regulation Accuracy
With Preset Voltages
D AutoCompt Dynamic Compensation of
Battery Pack’s Internal Impedance to Reduce
Charge Time
D Optional Cell-Temperature Monitoring Before
and During Charge
D Integrated Voltage and Current Regulation
With Programmable Charge-Current and High-
or Low-Side Current Sensing
D Integrated Cell Conditioning for Reviving
Deeply Discharged Cells and Minimizing Heat
Dissipation During Initial Stage Of Charge
D Charge Status Output for Single or Dual Led
or Host Processor Interface
D Automatic Battery-Recharge Feature
D Charge Termination by Minimum Current
D Automatic Low-Power Sleep Mode When V_CC
Is Removed
D EVMs Available for Quick Evaluation
D Packaging: 8-Pin SOIC, 8-Pin TSSOP, 8-Pin
MSOP
bq2057xSN or bq2057xTS
SOIC (SN) or TSSOP (TS) PACKAGE
(TOP VIEW)
SNS
1
BAT
2
VCC
3
TS
4
8
COMP
7
CC
6
VSS
5
STAT
DESCRIPTION
The BENCHMARQ bq2057 series advanced
Lithium-Ion (Li-Ion) and Lithium-Polymer (Li-Pol) linear
charge-management ICs are designed for cost-
sensitive and compact portable electronics. They
combine high-accuracy current and voltage regulation,
battery conditioning, temperature monitoring, charge
termination, charge-status indication, and AutoComp
charge-rate compensation in a single 8-pin IC. MSOP,
TSSOP, and SOIC package options are offered to fit a
wide range of end applications.
The bq2057 continuously measures battery
temperature using an external thermistor. For safety,
the bq2057 inhibits charge until the battery temperature
is within user-defined thresholds. The bq2057 then
charges the battery in three phases: conditioning,
constant current, and constant voltage. If the battery
voltage is below the low-voltage threshold, V_(min), the
bq2057 precharges using a low current to condition the
battery. The conditioning charge rate is approximately
10% of the regulation current. The conditioning current
also minimizes heat dissipation in the external pass-
element during the initial stage of the charge. After
conditioning, the bq2057 applies a constant current to
the battery. An external sense-resistor sets the current.
The sense-resistor can be on either the high or low side
of the battery without additional components. The
constant-current phase continues until the battery
reaches the charge-regulation voltage.
bq2057xDGK
MSOP (DGK) PACKAGE
(TOP VIEW)
VCC
1
TS
2
STAT
3
VSS
4
8
BAT
7
SNS
6
COMP
5
CC
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
AutoComp is a trademark of Texas Instruments.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
Copyright  2002, Texas Instruments Incorporated
www.ti.com
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