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9,7 mm x 6,4 mm
bq2084
SLUS550C 鈭?DECEMBER 2002 鈭?REVISED JULY 2004
SBS v1.1 COMPLIANT GAS GAUGE FOR
USE WITH THE bq29312
FEATURES
D
Provides Accurate Measurement of Available
Charge in Li-Ion and Li-Polymer Batteries
DESCRIPTION
The bq2084 SBS-compliant gas gauge IC for battery pack
or in-system installation maintains an accurate record of
available charge in Li-ion or Li-polymer batteries. The
bq2084 monitors capacity and other critical parameters of
the battery pack and reports the information to the system
host controller over a serial communication bus. It is
designed to work with the bq29312 analog front-end (AFE)
protection IC to maximize functionality and safety and
minimize component count and cost in smart battery
circuits. Using information from the bq2084, the host
controller can manage remaining battery power to extend
the system run time as much as possible.
The bq2084 uses an integrating converter with continuous
sampling for the measurement of battery charge and
discharge currents. Optimized for coulomb counting in
portable applications, the self-calibrating integrating
converter has a resolution better than 0.65-nVh and an
offset measurement error of less than 1-碌V (typical). For
voltage and temperature reporting, the bq2084 uses a
16-bit A-to-D converter. In conjunction with the bq29312,
the onboard ADC also monitors the pack and individual
cell voltages in a battery pack and allows the bq2084 to
generate the control signals necessary to implement the
cell balancing and the required safety protection for Li-ion
and Li-polymer battery chemistries.
The bq2084 supports the Smart Battery Data (SBData)
commands and charge-control functions. It communicates
data using the System Management Bus (SMBus) 2-wire
protocol. The data available include the battery鈥檚
remaining capacity, temperature, voltage, current and
remaining run-time predictions.
The bq2084 provides LED drivers and a push-button input
to depict remaining battery capacity from full to empty in
20%, 25%, or 33% increments with a 3-, 4-, or 5-segment
display.
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Supports the Smart Battery Specification
(SBS) V1.1
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Integrated Time Base Removes Need for
External Crystal with Optional Crystal input
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Works With the TI bq29312 Analog Front End
(AFE) Protection IC to Provide Complete Pack
Electronics for 7.2-V, 10.8-V or 14.4-V Battery
Packs With Few External Components
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Based on a Powerful Low-Power RISC CPU
Core With High-Performance Peripherals
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Integrated FLASH Memory Eliminates the
Need for External Configuration EEPROM
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Uses 16-Bit Delta Sigma Converter for
Accurate Voltage and Temperature
Measurements
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Measures Charge Flow Using a High
Resolution 16-Bit Integrating Converter
鈭?Better Than 0.65-nVh of Resolution
鈭?Self-Calibrating
鈭?Offset Error Less Than 1-碌V
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Programmable Cell Modeling for Maximum
Battery Fuel Gauge Accuracy
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Drives 3-, 4-, or 5-Segment LED Display for
Remaining Capacity Indication
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38-Pin TSSOP (DBT)
APPLICATIONS
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Notebook PCs
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Medical and Test Equipment
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Portable Instrumentation
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.
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
錚?/div>
2004, Texas Instruments Incorporated
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