bq20851-V1P2

SLUS575 − AUGUST 2003

SBSCOMPLIANT GAS GAUGE IC

FOR USE WITH THE bq29311

FEATURES

Charge in Li-Ion and Li-Polymer Batteries

(SBS) V1.1

External Crystal

(AFE) Protection IC to Provide Complete Pack

Electronics for 10.8-V or 14.4-V Battery Packs

With Few External Components

Core With High-Performance Peripherals

for External Configuration EEPROM

Resolution 16-Bit Integrating Converter

− Better Than 3-nVh of Resolution

− Self-Calibrating

− Offset Error Less Than 1-

µV

Accurate Voltage and Temperature

Measurements

Battery Fuel Gauge Accuracy

Remaining Capacity Indication

APPLICATIONS

DESCRIPTION

The bq20851−V1P2 SBS-compliant gas gauge IC for

battery pack installation maintains an accurate record of

available charge in Li-ion or Li-polymer batteries. The

bq20851−V1P2 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

bq20851−V1P2,

the

host

controller

can

manage

remaining battery power to extend the system run time as

much as possible.

BLOCK DIAGRAM

ADC

Voltage

Sense

Resistor

(10 m

Ω - 20 mΩ)

Pack−

Integrating

ADC

Coulomb

Counting

Temp

Sensor

512 Bytes

Config.

Flash

EPROM

bq20851−V1P2

Level

Translator

bq29311

LDO

Glueless

Interface

Cell Inputs

Safety Control

SMBus

Pack+

Supply Voltage

Li-Ion

Cells

−

+

Charge/Discharge

Power FETs

−

+

−

+

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.

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.

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Copyright

 2003, Texas Instruments Incorporated