bq29312

SLUS546D − MARCH 2003 − REVISED SEPTEMBER 2004

THREE AND FOUR CELL LITHIUMION OR

LITHIUMPOLYMER BATTERY PROTECTION AFE

PW

RGE

FEATURES

Gauges

Voltage to Battery Management Host

to Battery Information

Load and Short Circuit During Charge and

Discharge

and Ship Mode

APPLICATIONS

DESCRIPTION

The bq29312 is a 2-, 3-, or 4-cell lithium-ion battery pack

protection analog front end (AFE) IC that incorporates a

3.3-V, 25-mA low-dropout regulator (LDO). The bq29312

battery parameters such as cell voltages and control

output status. Other parameters such as current protection

thresholds and delays can be programmed into the

bq29312 to increase the flexibility of the battery

management system.

The bq29312 provides safety protection for overcharge,

overload, short-circuit, overvoltage, and undervoltage

conditions in conjunction with the battery management

host. In overload and short-circuit conditions, the bq29312

turns the FET drive off autonomously dependant on the

internal configuration setting.

SYSTEM PARTITIONING DIAGRAM

LDO, Therm Output Drive & UVLO

Power Management

LDO, TOUT and Power mode control

I2C

Capacity Prediction <1% Error

SMBus

Pack +

Pack −

Discharge / Charge /

Pre−Charge FETs

Cell and Pack

Voltage

Measurement

Pre−Charge

FET Drive

2−Tier Over Current Protection

32kHz Clock

Generator

bq2084

768 Bytes of

User Flash

Fuse

1st Level OV and

UV Protection

Pack Under Voltage

Power Mode

Control

Pre-charge Control

Delay Counters

Cell Balancing Algorithm and Control

Cell Balancing

Drive

System Interface

System Watchdog

Voltage Level Translator

System Interface

32kHz

Power Mode Control

Fail-Safe Protection

T1

1st Level OC

Protection

Temperature Measurement

<1% Error

TINT

Supply Voltage

bq29312

PCH FET Drive

RAM Registers

SBS v1.1 Data

bq29312 RAM/Comms Validation

XAlert

Sleep

Sense Resistor

(10 − 30 m

Ω)

PF Input

PRODUCTION DATA information is 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.

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 data sheet.

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Copyright

 2004, Texas Instruments Incorporated