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1 Features
• AFE monitoring features
– Pure digital interface
– Internal ADC measures cell voltage, die
temperature, and external thermistor
– A separate, internal ADC measures pack
current (coulomb counter)
– Directly supports up to three thermistors
(103AT)
• Hardware protection features
– Overcurrent in Discharge (OCD)
– Short Circuit in Discharge (SCD)
– Overvoltage (OV)
– Undervoltage (UV)
– Secondary protector fault detection
• Additional features
– Integrated cell balancing FETs
– Charge, discharge low-side NCH FET drivers
– Alert interrupt to host microcontroller
– 2.5-V or 3.3-V output voltage regulator
– No EEPROM programming necessary
– High supply voltage absolute maximum (up to
108 V)
– Simple I2C compatible interface (CRC option)
– Random cell connection tolerant
3 Description
The BQ769x0 family of robust analog front-end
(AFE) devices serves as part of a complete pack
monitoring and protection solution for next-generation,
high-power systems, such as light electric vehicles,
power tools, and uninterruptible power supplies. The
BQ769x0 is designed with low power in mind: Subblocks within the IC may be enabled or disabled to
control the overall chip current consumption, and a
SHIP mode provides a simple way to put the pack into
an ultra-low power state.
The BQ76920 device supports up to 5-series cells
or typical 18-V packs, the BQ76930 handles up
to 10-series cells or typical 36-V packs, and the
BQ76940 works for up to 15-series cells or typical
48-V packs. A variety of battery chemistries may be
managed with these AFEs, including Li-ion, Li-iron
phosphate, and more. Through I2C, a host controller
can use the BQ769x0 to implement many battery
pack management functions, such as monitoring (cell
voltages, pack current, pack temperatures), protection
(controlling charge/discharge FETs), and balancing.
Integrated A/D converters enable a purely digital
readout of critical system parameters, with calibration
handled in TI’s manufacturing process.
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