1FEATURES

• Provides Accurate Measurement of Available

Charge in NiCd, NiMH, Li-Ion, and Lead-Acid

Batteries

• Supports SBS Smart Battery Data

Specification v1.1

• Supports the 2-Wire SMBus v1.1 Interface With

PEC or 1-Wire HDQ16

• Reports Individual Cell Voltages

• Monitors and Provides Control to Charge and

Discharge FETs in Li-Ion Protection Circuit

• Provides 15-Bit Resolution for Voltage,

Temperature, and Current Measurements

• Measures Charge Flow Using a V-to-F

Converter With Offset of Less Than 16 μV After

Calibration

• Consumes Less Than 0.5 mW Operating

• Drives a 4- or 5-Segment LED Display for

Remaining Capacity Indication

• 28-Pin 150-Mil (3,8-mm) SSOP

DESCRIPTION

The bq2060A SBS-compliant gas gauge IC for

battery pack or in-system installation maintains an

accurate record of available charge in rechargeable batteries. The bq2060A monitors capacity and other

critical battery parameters for NiCd, NiMH, Li-ion, and

lead-acid chemistries. The bq2060A uses a

voltage-to-frequency converter with automatic offset

error correction for charge and discharge counting.

For voltage, temperature, and current reporting, the

bq2060A uses an A-to-D converter. The onboard

ADC also monitors individual cell voltages in a Li-ion

battery pack and allows the bq2060A to generate

control signals that may be used with a pack

supervisor to enhance pack safety.

The bq2060A supports the smart battery data

(SBData) commands and charge-control functions. It

communicates data using the system management

bus (SMBus) 2-wire protocol or the Benchmarq 1-wire

HDQ16 protocol. The data available include the

remaining battery capacity, temperature, voltage,

current, and remaining run-time predictions. The

bq2060A provides LED drivers and a pushbutton

input to depict remaining battery capacity from full to

empty in 20% or 25% increments with a 4- or

5-segment display.

The bq2060A works with an external EEPROM. The

EEPROM stores the configuration information for the

bq2060A, such as battery chemistry, self-discharge

rate, rate compensation factors, measurement

calibration, and design voltage and capacity. The

bq2060A uses the programmable self-discharge rate and other compensation factors stored in the

EEPROM to accurately adjust remaining capacity for

use and standby conditions based on time, rate, and

temperature. The bq2060A also automatically

calibrates or learns the true battery capacity in the

course of a discharge cycle from near-full to

near-empty levels.

The REG output regulates the operating voltage for

the bq2060A from the battery cell stack using an

external JFET.