BQ29312_15 Datasheet, PDF (1/39 Pages) Texas Instruments – FOUR CELL LITHIUM-ION

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PW
bq29312
SLUS546E – MARCH 2003 – REVISED MARCH 2005
THREE AND FOUR CELL LITHIUM-ION OR
LITHIUM-POLYMER BATTERY PROTECTION AFE
FEATURES
• 2-, 3-, or 4-Cell Series Protection Control
• Can Directly Interface With the bq2084 Gas
Gauges
• Provides Individual Cell Voltages and Battery
Voltage to Battery Management Host
• Integrated Cell Balancing Drive
• I²C Compatible User Interface Allows Access
to Battery Information
• Programmable Threshold and Delay for Over
Load and Short Circuit During Charge and
Discharge
• System Alert Interrupt Output
• Host Control Can Initiate Sleep Power Mode
and Ship Mode
• Integrated 3.3-V, 25-mA LDO
• Supply Voltage Range From 4.5 V to 25 V
• Low Supply Current of 60-µA Typical
APPLICATIONS
• Notebook PCs
• Medical and Test Equipment
• 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 I²C compat-
ible interface to extract battery parameters such as
cell voltages and control output status. Other par-
ameters 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 over-
charge, overload, short-circuit, overvoltage, and
undervoltage conditions in conjunction with the bat-
tery 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
Fuse
Pack +
bq2084
PF Input
Pre-charge Control Fail-Safe Protection
Power Management
LDO, TOUT and Power mode control
Supply Voltage
Temperature Measurement _TINT
<1% Error
768 Bytes of
User Flash
32kHz Clock
Generator
T1
32kHz
SMBus
Cell Balancing Algorithm and Control
SBS v1.1 Data
System Interface
I2C
bq29312 RAM/Comms Validation
1st Level OC
Protection
1st Level OV and
UV Protection
XAlert
Sleep
Pack Under Voltage
Power Mode
Control
Cell and Pack
Voltage
Measurement
Capacity Prediction <1% Error
Discharge / Charge /
Pre-Charge FETs
bq29312
PCH FET Drive
Pre-Charge
FET Drive
Cell Balancing
Drive
LDO, Therm Output Drive & UVLO
System Watchdog Delay Counters
System Interface RAM Registers
Power Mode Control
2-Tier Over Current Protection
Voltage Level Translator
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 the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2003–2005, Texas Instruments Incorporated