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1

INTRODUCTION

1.1 FEATURES

1.2

APPLICATIONS

1.3

DESCRIPTION

HostSystem

SingleCellLi-Ion

BatteryPack

PACK-

PROTECTION

IC

CHG

DSG

Temp

Sense

Battery

Good

Current

Sense

I2C

T

LDO

PACK+

Voltage

Sense

Battery

Low

Warning

FETs

bq27500/1

RID

RID

Sense*

*bq27501Only

Power

Management

Controller

bq27500

bq27501

System-Side Impedance Track™ Fuel Gauge

SLUS785 – SEPTEMBER 2007

• Battery Fuel Gauge for 1-Series Li-Ion

• Smartphones

Applications

• PDAs

• Resides on System Main Board

• Digital Still and Video Cameras

–

Works with Embedded or Removable

• Handheld Terminals

Battery Packs

• MP3 or Multimedia Players

• Two Varieties

–

bq27500: Uses PACK+, PACK-, and T

Battery Terminals

–

bq27501: Includes Battery Pack ID Resistor

(RID) Terminal

The Texas Instruments bq27500/01 System-Side

Li-Ion Battery Fuel Gauge is a micro-controller

• Micro-Controller Peripheral Provides:

peripheral that provides fuel gauging for single cell

–

Accurate Battery Fuel Gauging

Li-Ion battery packs. The device requires little system

–

Internal Temperature Sensor for System

micro-controller

firmware

development.

The

Temperature Reporting

bq27500/01 resides on the system’s main board, and

–

Battery Low Interrupt Warning

manages an embedded battery (non-removable) or a

–

Battery Insertion Indicator

removable battery pack.

–

Battery ID Detection

–

96 bytes of Non-Volatile Scratch Pad

The

bq27500/01

uses

the

patented

Impedance

FLASH

Track™ algorithm for fuel gauging, and provides

information

such

as

remaining

battery

capacity

• Battery Fuel Gauge Based on Patented

(mAh), state-of-charge (%), run-time to empty (min.),

Impedance Track™ Technology

battery voltage (mV), and temperature (

°C).

–

Models the Battery Discharge Curve for

Accurate Time-to-Empty Predictions

Battery fuel gauging with the bq27500 requires only

–

Automatically Adjusts for Battery Aging,

PACK+

(P+),

PACK-

(P-),

and

Thermistor

(T)

Battery Self Discharge, and

connections

to

a

removable

battery

pack

or

Temperature/Rate Inefficiencies

embedded battery circuit. The bq27501 works with

–

Low Value Sense Resistor (10m

Ω or Less)

identification resistors in battery packs, to gauge

batteries of different fundamental chemistries and/or

Micro-Controller Port

significantly different rated capacities.

• 12-Pin 2,5 mm × 4,0 mm SON Package

TYPICAL APPLICATION

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 document.

Impedance Track is a trademark of Texas Instruments.

UNLESS

OTHERWISE

NOTED

this

document

contains

Copyright © 2007, Texas Instruments Incorporated

PRODUCTION DATA information 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.