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.