1

INTRODUCTION

1.1 FEATURES

1.2

APPLICATIONS

1.3

DESCRIPTION

HostSystem

Power

Management

Controller

I C

2

LDO

Battery

Low

Warning

bq27500/1

Battery

Good

Voltage

Sense

RID

Sense*

Temp

Sense

Current

Sense

PACK–

PACK+

T

Single-CellLi-Ion

BatteryPack

FETs

CHG

DSG

Protection

IC

*bq27501Only

RID

bq27500

bq27501

System-Side Impedance Track™ Fuel Gauge

www.ti.com

SLUS785D – SEPTEMBER 2007 – REVISED APRIL 2008

• 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: Works With Battery ID Resistor in

Battery Pack

The Texas

Instruments

bq27500/01

system-side

Li-Ion

battery

fuel

gauge

is

a

microcontroller

• Microcontroller 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

microcontroller

firmware

development.

The

Temperature Reporting

bq27500/01 resides on the system 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.

The

bq27501

works

with

–

Low-Value Sense Resistor (10 m

Ω or Less)

identification resistors in battery packs to gauge

batteries of different fundamental chemistries and/or

Microcontroller Port

significantly different rated capacities.

• 12-Pin 2,5-mm × 4-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.

PRODUCTION DATA information is current as of publication date.

Copyright © 2007–2008, Texas Instruments Incorporated

Products conform to specifications per the terms of the Texas

Instruments standard warranty. Production processing does not

necessarily include testing of all parameters.