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RGE
bq29312
SLUS546D − MARCH 2003 − REVISED SEPTEMBER 2004
THREE AND FOUR CELL LITHIUM ION OR
LITHIUM POLYMER BATTERY PROTECTION AFE
FEATURES
D
2-, 3-, or 4-Cell Series Protection Control
D
Can Directly Interface With the bq2084 Gas
Gauges
APPLICATIONS
D
Notebook PCs
D
Medical and Test Equipment
D
Portable Instrumentation
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
also integrates an I
2
C compatible interface to extract
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.
D
Provides Individual Cell Voltages and Battery
Voltage to Battery Management Host
D
Integrated Cell Balancing Drive
D
I
2
C Compatible User Interface Allows Access
to Battery Information
D
Programmable Threshold and Delay for Over
Load and Short Circuit During Charge and
Discharge
D
System Alert Interrupt Output
D
Host Control Can Initiate Sleep Power Mode
and Ship Mode
D
Integrated 3.3-V, 25-mA LDO
D
Supply Voltage Range From 4.5 V to 25 V
D
Low Supply Current of 60-µA Typical
SYSTEM PARTITIONING DIAGRAM
Fuse
Pack +
bq2084
Pre-charge Control Fail-Safe Protection
Power Management
LDO, TOUT and Power mode control
Temperature Measurement
<1% Error
768 Bytes of
User Flash
SMBus
TINT
Supply Voltage
PF Input
Discharge / Charge /
Pre−Charge FETs
bq29312
PCH FET Drive
Pre−Charge
FET Drive
Cell Balancing
Drive
T1
32kHz
LDO, Therm Output Drive & UVLO
System Watchdog
Delay Counters
32kHz Clock
Generator
Cell Balancing Algorithm and Control
SBS v1.1 Data
System Interface
I2 C
XAlert
Sleep
Power Mode Control
System Interface
RAM Registers
bq29312 RAM/Comms Validation
1st Level OC
Protection
Pack Under Voltage
Power Mode
Control
1st Level OV and
UV Protection
Cell and Pack
Voltage
Measurement
2−Tier Over Current Protection
Voltage Level Translator
Capacity Prediction <1% Error
Pack −
Sense Resistor
(10 − 30 mΩ)
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.
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.
Copyright
2004, Texas Instruments Incorporated
2nd Level Over Voltage Protection
TI [ TEXAS INSTRUMENTS ]
