1 Features

• Ultra-low quiescent current: 8 μA typ. (NORMAL

mode), 2 μA (HIBERNATE mode)

• Full suite of voltage, current, and temperature

protections

• Smart passive cell balancing removes cell-to-cell

imbalance

• Scalable cell count from 3 series to 20 series or

more

• Voltage protection (accuracy ±10 mV for OV,

±18 mV for UV)

– Overvoltage: 3 V to 4.575 V

– Undervoltage: 1.2 V to 3 V

• Open cell and open-wire detection (OW)

• Current protection

– Overcurrent discharge 1: –10 mV to –85 mV

– Overcurrent discharge 2: –20 mV to –170 mV

– Short-circuit discharge: –40 mV to –340 mV

• Temperature protection

– Overtemperature charge: 45°C or 50°C

– Overtemperature discharge: 65°C or 70°C

• Additional features:

– Independent charge (CHG) and discharge

(DSG) FET drivers

– Smart cell balancing algorithm with integrated

FETs (up to 50-mA balancing current), also

supports external FETs for higher cell-balancing

current

– Ultra-low power HIBERNATE mode

– High 36-V absolute maximum rating per cell

input

– Resistor programmable overcurrent (OCD1/2)

delay

• SHUTDOWN mode: 0.5-μA maximum

• Functional Safety-Capable

– Documentation available to aid functional safety

system design

2 Applications

• Power tools, garden tools

• Robotic cleaners, vacuum cleaners, hoverboards

• e-bikes

• 10.8-V to 72-V packs

3 Description

The BQ77915 device is a low-power battery pack

protector that implements a suite of voltage, current,

and temperature protections and a smart cell

balancing algorithm without microcontroller (MCU)

control. The device's stackable interface provides

simple scaling to support battery cell applications from

3 series to 20 series or more. Protection thresholds

and delays are factory-programmed and available in

a variety of configurations. Separate overtemperature

and undertemperature thresholds for discharge (OTD

and UTD) and charge (OTC and UTC) are provided

for added flexibility.