Texas Instruments BQ76942 Manual

BQ76942 3-Series to 10-Series High Accuracy Battery Monitor and Protector for

1 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 µA to
10 µA
– SHUTDOWN Mode: 1 µA
• High-voltage tolerance of 85 V on cell connect and
select additional pins
• Tolerant of random cell attach sequence on
production line
• 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 I
and HDQ one-wire interface
• Dual programmable LDOs for external system
usage
• 48-pin TQFP package (PFB)
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.
Li-Ion, Li- Polymer, and LiFePO
2
C, SPI,
SLUSE14B – DECEMBER 2020 – REVISED DECEMBER 2021
Battery Packs
4

2 Applications

• Cordless power tools and garden tools
• Vacuum cleaners
• E-bike, e-scooter, and LEV
• Non-military drones
• Other industrial battery pack (3-series–10-series)

3 Description

The Texas Instruments
integrated, high accuracy
protector for 3-series to 10-series Li-ion, Li-polymer,
and LiFePO battery packs. The device includes a
4
high-accuracy monitoring
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
2
400-kHz I C, SPI, and HDQ one-wire standards. The
BQ76942 is available in a 48-pin TQFP package.
Device Information
(1)
PART NUMBER PACKAGE
BQ76942xx PFB (48-pin)
(1) See the Device Comparison Table
device family. For all available devices, see the orderable
addendum at the end of the data sheet.
+
NC
VC9
+
NC
VC8
+
NC
VC7
+
NC
VC6
+
NC
VC5
+
NC
VC4
+
+
+
+
Simplified Schematic
BQ76942
BQ76942 is a highly
battery monitor and
system, a highly
BODY SIZE (NOM)
7 mm × 7 mm
for information on the
PACK+
CHG DSG
COMMUNICATIONS
5V
COMM TO
TRANSCEIVER
SYSTEM
COMM
REGIN
REG1
REG2 VDD
3.3V
RST_SHUT
DDSG
MCU
DCHG
DFETOFF
CFETOFF
HDQ
SDA
SCL
ALERT
GND
PACK-