FEATURES

· Provides Accurate Measurement of Available

Charge in Li-Ion and Li-Polymer Batteries

· Supports the Smart Battery Specification

(SBS) V1.1

· Integrated Time Base Removes Need for

External Crystal with Optional Crystal input

· 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

· Based on a Powerful Low-Power RISC CPU

Core With High-Performance Peripherals

· Integrated Flash Memory Eliminates the Need

for External Configuration EEPROM

· Uses 16-Bit Delta Sigma Converter for

Accurate Voltage and Temperature

Measurements

· Measures Charge Flow Using a High

Resolution 16-Bit Integrating Converter

– Better Than 0.65-nVh of Resolution

– Self-Calibrating

– Offset Error Less Than 1-μV

· Programmable Cell Modeling for Maximum

Battery Fuel Gauge Accuracy

· Drives 3-, 4-, or 5-Segment LED Display for

Remaining Capacity Indication

· Available in a 38-Pin TSSOP (DBT) Package

APPLICATIONS

· Notebook PCs

· Medical and Test Equipment

· Portable Instrumentation

DESCRIPTION

The bq2084-V143 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-V143 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 AFE protection

IC to maximize functionality and safety and minimize

component count and cost in smart battery circuits.

Using information from the bq2084-V143, the host

controller can manage remaining battery power to

extend the system run time as much as possible.

The bq2084-V143 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-μV (typical). For voltage and

temperature reporting, the bq2084-V143 uses a

16-bit A-to-D converter. With the bq29312, the

onboard ADC also monitors the pack and individual

cell voltages in a battery pack and allows the

bq2084-V143 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-V143 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's remaining capacity,

temperature, voltage, current, and remaining

run-time predictions.

The bq2084-V143 provides LED drivers and a

pushbutton input to depict remaining battery capacity

from full to empty in 20%, 25%, or 33% increments

with a 3-, 4-, or 5-segment display.