bq77910
www.ti.com
SLUSA07B –AUGUST 2010–REVISED MAY 2011
Stand-Alone Multi-Cell Lithium-Ion/Polymer Precision Protectors
Check for Samples: bq77910
Automatic cell balancing is provided using internal
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FEATURES
50-mA cell circuits. A robust balancing algorithm
ensures optimum performance by maintaining all cell
voltages in balance. Balancing may be configured to
operate at all times, only during charge, or can be
disabled completely.
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4-, 5-, 6-, 7-, 8-, 9-, or 10 Series Cell Protection
Individual Cell-Voltage Monitoring
Low-Side NMOS FET Drive for Charge and
Discharge Control
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Compatible With 1-mΩ Current-Sense Resistor
Supply-Voltage Range From 5.6 V to 50 V
Integrated 3.3-V Micro-Power LDO Regulator
Low Supply Current
Additional advanced safety features of the bq77910
include the ability to control split power-path
MOSFETs, an open-cell sense-line detection
mechanism, and the ability to detect an open or
shorted external temperature sensor.
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Normal Mode: 50 µA, Typical
Shutdown Mode, LDO OFF: 3 µA, Typical
Programmable Protection Functions
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Wide range of programmable detection thresholds
and delay times
Configurable for multiple cell types and application
requirements:
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38-Pin TSSOP Package
Internal 50-mA Automatic Cell Balancing
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APPLICATIONS
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Cell overvoltage
Cell undervoltage
Pack discharge overcurrent
Pack discharge short circuit
Pack charge short-circuit current
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Cordless Power Tools
Cordless Lawn Equipment
Electric Bikes
UPS
Medical Equipment
Light Electric Vehicles (LEV)
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Variable gain (×1 or ×5) current-sense circuit
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Compatible with a wide range of current-sense
resistors (1 mΩ to 5 mΩ typical) sized for
application requirements
DESCRIPTION
The bq77910 precision protector is a complete
stand-alone, self-contained battery-protection and
cell-balancing device intended for Li-ion/polymer
battery packs.
Fixed Hardware Protection Functions
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Preset overtemperature protections
Open-cell detection
Open and shorted thermistor detection
Brownout protection quickly shuts off FETs under
low battery conditions to avoid FET overheating
The bq77910 monitors 4 to 10 series individual cell
voltages and provides fast-acting outputs which may
be used to drive N-channel MOSFETs to interrupt the
power path. Activation delays and recovery methods
for each safety condition are fully programmable in
non-volatile memory.
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Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCTION DATA information is current as of publication date.
Copyright © 2010–2011, 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.