BQ2085 Datasheet, PDF (1/56 Pages) Texas Instruments – SBS-COMPLIANT GAS GAUGE IC FOR USE WITH THE bq29311

bq2085
SBS-COMPLIANT GAS GAUGE IC
FOR USE WITH THE bq29311
SLUS541 – OCTOBER 2002
FEATURES
D Provides Accurate Measurement of Available
Charge in Li-Ion and Li-Polymer Batteries
D Supports the Smart Battery Specification
(SBS) V1.1
D Integrated Time Base Removes Need for
External Crystal
D Works With the TI bq29311 Analog Front End
(AFE) Protection IC to Provide Complete Pack
Electronics for 10.8-V or 14.4-V Battery Packs
With Few External Components
D Based on a Powerful Low-Power RISC CPU
Core With High-Performance Peripherals
D Integrated FLASH Memory Eliminates the
Need for External Configuration EEPROM
D Measures Charge Flow Using a High
Resolution 16-Bit Integrating Converter
– Better Than 3-nVh of Resolution
– Self-Calibrating
– Offset Error Less Than 1-µV
D Uses 16-Bit Delta Sigma Converter for
Accurate Voltage and Temperature
Measurements
BLOCK DIAGRAM
D Programmable Cell Modeling for Maximum
Battery Fuel Gauge Accuracy
D Drives 3-, 4-, or 5-Segment LED Display for
Remaining Capacity Indication
D 38-Pin TSSOP (DBT)
APPLICATIONS
D Notebook PCs
D Medical and Test Equipment
D Portable Instrumentation
DESCRIPTION
The bq2085 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 bq2085 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
bq29311 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 bq2085, the host controller
can manage remaining battery power to extend the
system run time as much as possible.
Pack+
SMBus
Pack–
Charge/Discharge
Power FETs
Supply Voltage
bq2085
Temp
Sensor
512 Bytes
Config.
FLASH
EPROM
ADC
Voltage
Integrating
ADC
Coulomb
Counting
Glueless
Interface
Cell Inputs
Safety Control
LDO
bq29311
Level
Translator
+
–
+ Li-Ion
– Cells
+
–
Sense
Resistor
(10 mΩ - 20 mΩ)
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  2002, Texas Instruments Incorporated
www.ti.com
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