The Texas Instruments BQ76942
device
is a highly integrated, high accuracy battery monitor and
protector for 3-series to 10-series Li-ion, Li-polymer, and LiFePO4
battery packs. The device includes a high accuracy monitoring system, a highly
configurable protection subsystem, and support for autonomous or host controlled
cell balancing. Integration includes high-side charge-pump NFET drivers, dual
programmable LDOs for external system use, and a host communication peripheral
supporting 400-kHz I2C, SPI, and HDQ one-wire standards. The
following are the device features:
- Battery monitoring capability
for 3-series to 10-series cells
- Integrated charge pump for
high-side NFET protection with optional autonomous recovery
- Extensive protection suite including voltage, temperature,
current, and internal diagnostics
- Two independent ADCs
- Support for
simultaneous current and voltage sampling
- High-accuracy coulomb
counter with input offset error < 1 µV (typical)
- High accuracy cell voltage measurement < 10 mV
(typical)
- Wide-range current
applications (±200-mV measurement range across sense resistor)
- Integrated secondary chemical fuse drive protection
- Autonomous or host-controlled cell balancing
- Multiple power modes (typical
battery pack operating range conditions)
- NORMAL mode: 286
µA
- Multiple SLEEP mode
options: 24 µA to 41 µA
- Multiple DEEPSLEEP
mode options: 9.2 µA to 10.7 µA
- SHUTDOWN mode: 1 µA
- High-voltage tolerance of 85 V on cell connect and select
additional pins
- Support for temperature sensing using internal sensor and up
to nine external thermistors
- Integrated one-time-programmable (OTP) memory programmable
by customers on production line
- Communication options include 400-kHz I2C, SPI,
and HDQ one-wire interface
- Dual programmable LDOs for
external system usage