FEATURES

· Next Generation Patented Impedance Track™

Technology accurately Measures Available

Charge in Li-Ion and Li-Polymer Batteries

· Better than 1% Error Over Lifetime of the

Battery

· Instant Accuracy – No Learning Cycle

Required

· Supports the Smart Battery Specification SBS

V1.1

· Powerful 8-Bit RISC CPU With Ultra-Low

Power Modes

· Works With the TI bq29330 Analog Front-End

(AFE) Protection IC to Provide Complete Pack

Electronics Solution

· Full Array of Programmable Protection

Features

– Voltage, Current and Temperature

· Fully Integrated High Accurate Clock

· Flexible Configuration for 2 to 4 Series Li-Ion

and Li-Polymer Cells

· Integrated Field Programmable FLASH

Memory Eliminates the Need for External

Configuration Memory

· Smart Battery Charger Control Feature

· Two 16-Bit Delta-Sigma Converter

– Accurate Voltage and Temperature

Measurements

– Integrating Coloumb Counter for Charge

Flow

– Better Than 0.65 nVh of Resolution

– Self-Calibrating

· Supports SHA-1 Authentication

· 20-Pin TSSOP (PW)

APPLICATIONS

· Notebook PCs

· Medical and Test Equipment

· Portable Instrumentation

DESCRIPTION

The bq20z70 SBS-compliant gas gauge IC,

incorporating patented Impedance Track™

technology, is designed for battery-pack or in-system

installation. The bq20z70 measures and maintains

an accurate record of available charge in Li-ion or

Li-polymer batteries using its integrated

high-performance analog peripherals. The bq20z70

monitors capacity change, battery impedance,

open-circuit voltage, 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 bq29330 analog

front-end (AFE) protection IC to maximize

functionality and safety, and minimize component

count and cost in smart battery circuits.

The Impedance Track technology continuously

analyzes the battery impedance, resulting in superior

gas-gauging accuracy. This enables remaining

capacity to be calculated with discharge rate, temperature, and cell aging all accounted for during

each stage of every cycle.