Product details


Cell chemistry Li-Ion/Li-Polymer, LiFePO4 Number of series cells 2-4 Cells, Single Cell Communication interface SMBus Battery capacity (Min) (mAh) 100 Battery capacity (Max) (mAh) 29000 Implementation Pack External capacity indication LED Features Cell Balancing, Impedance Track™ algorithm, Integrated Protector, SHA-1 Authentication, Turbo Mode Operating temperature range (C) -40 to 85 Cell balancing External, Internal open-in-new Find other Battery fuel gauges

Package | Pins | Size

VQFN (RSM) 32 16 mm² 4 x 4 open-in-new Find other Battery fuel gauges


  • Fully integrated 1-series, 2-series, 3-series, and 4-series li-ion or li-polymer cell battery pack manager and protection
  • Next-generation patented Impedance Track™ technology accurately measures available charge in li-ion and li-polymer batteries
  • High-side N-CH protection FET drive
  • Integrated cell balancing while charging or at rest
  • Suitable for batteries between 100 mAh and 29 Ah
  • Full array of programmable protection features
    • Voltage
    • Current
    • Temperature
    • Charge timeout
    • CHG/DSG FETs
    • AFE
  • Sophisticated charge algorithms
    • JEITA
    • Enhanced charging
    • Adaptive charging
    • Cell balancing
  • Supports TURBO mode 2.0
  • Supports battery trip point (BTP)
  • Diagnostic lifetime data monitor and black box recorder
  • LED display
  • Supports two-wire SMBus v1.1 interface
  • SHA-1 authentication
  • IATA support
  • Compact package: 32-lead QFN (RSM)

All trademarks are the property of their respective owners.

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The BQ40Z50-R2 device, incorporating patented Impedance Track™ technology, is a fully integrated, single-chip, pack-based solution that provides a rich array of features for gas gauging, protection, and authentication for 1-series, 2-series, 3-series, and 4-series cell Li-Ion and Li-Polymer battery packs.

Using its integrated high-performance analog peripherals, the BQ40Z50-R2 device measures and maintains an accurate record of available capacity, voltage, current, temperature, and other critical parameters in Li-Ion or Li-Polymer batteries, and reports this information to the system host controller over an SMBus v1.1 compatible interface.

The BQ40Z50-R2 device supports TURBO Mode 2.0 by providing the available max power and max current to the host system. The device also supports Battery Trip Point to send a BTP interrupt signal to the host system at the preset state of charge thresholds.

The BQ40Z50-R2 provides software-based 1st- and 2nd-level safety protection against overvoltage, undervoltage, overcurrent, short-circuit current, overload, and overtemperature conditions, as well as other pack- and cell-related faults.

SHA-1 authentication, with secure memory for authentication keys, enables identification of genuine battery packs.

The compact 32-lead QFN package minimizes solution cost and size for smart batteries while providing maximum functionality and safety for battery gauging applications.

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More information

The latest firmware release is now available Request now

Technical documentation

= Top documentation for this product selected by TI
No results found. Please clear your search and try again. View all 13
Type Title Date
* Datasheet BQ40Z50-R2 1-Series, 2-Series, 3-Series, and 4-Series Li-Ion Battery Pack Manager datasheet (Rev. B) Jan. 17, 2020
* User guide BQ40Z50-R2 Technical Reference Manual (Rev. B) Oct. 12, 2018
Application note Multibattery management in medical ultrasound systems (Rev. A) Jan. 21, 2021
Application note Advanced Charge Algorithm Application Note Aug. 02, 2018
Application note bq40z50-R2 v2.08 to v2.11 Change List (Rev. A) Apr. 24, 2018
User guide bq40z50-R2 v2.08 Required Changes Oct. 11, 2017
Application note bq40z50-R1 to bq40z50-R2 Change List Jul. 13, 2017
Application note Turbo Mode 1.0 Setup Steps Dec. 13, 2016
Application note SMBus Made Simple Nov. 09, 2016
User guide bq40z50EVM Li-Ion Battery Pack Manager Evaluation Module (Rev. B) Sep. 20, 2016
Application note bq40z50 Data Memory Programming for Mass Production Apr. 01, 2015
Application note bq40zxx Manufacture, Production, and Calibration (Rev. A) Mar. 23, 2015
Application note bq40z50 Advanced Gas Gauge Circuit Design (Rev. A) Sep. 23, 2014

Design & development

For additional terms or required resources, click any title below to view the detail page where available.

Hardware development

document-generic User guide

BQ40z50EVM is a complete system useful for evaluating the functionality of the bq40z50 fuel gauge. As described on the BQ40z50 product folder, this gauge is appropriate for applications powered by multi-cell battery systems. The EVM includes one bq40z50 circuit module, a current sense resistor, and (...)

  • Populated circuit module for quick setup
  • Software allows data logging for system analysis
  • Complete evaluation system for the bq40z50 battery management IC

Software development

Gauging Parameter Calculator: Match chemistry for Impedance Track gauges
GPCCHEM GPC Chemistry ID matching for Impedance Track (IT) algorithm gas gauges (Find closest chemistry match) must be done before Optimizing room temperature or low temperature performance.

Gauging Parameter Calculator Chemistry ID matching for Impedance track gas gauges (GPCCHEM) is a math calculation and (...)

BQ40Z50-R3 device firmware: 1-4 series Li-ion battery pack manager | battery fuel (gas) gauge
BQ40Z50-R3-DEVICE-FW — The BQ40Z50-R3 is a FW only release that can be flashed onto any existing BQ40Z50 hardware such as the BQ40Z50-R2, BQ40Z50-R1, or BQ40Z50 device. The firmware incorporates the patented Impedance Track™ technology to create a pack-based solution that provides a rich array of features for gas (...)
  • The BQ40Z50-R3 firmware is usable on any previous version of the BQ40Z50 hardware
  • Supports Intel® dynamic battery power technology (Intel® DBPT) version 3.0 by providing the available max power, max current, Vload and Rhfeffective
  • New expanded lifetime logging capabilities with customer configurable (...)
SLUC628A.ZIP (4249 KB)
SLUC649.ZIP (4243 KB)
SLUC671.ZIP (4261 KB)

Reference designs

1 to 4 Series Cell Li-Ion Battery Pack Manager Reference Design
TIDA-00883 The Texas Instruments bq40z50-R1 device is a Battery Pack Manager that integrates gas gauging, and protection for completely autonomous operation of 1-series to 4-series cell Li-Ion and Li-Polymer battery packs. The architecture enables communication between the fuel gauging processor and an (...)
document-generic Schematic document-generic User guide

CAD/CAE symbols

Package Pins Download
VQFN (RSM) 32 View options

Ordering & quality

Information included:
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  • Device marking
  • Lead finish/Ball material
  • MSL rating/Peak reflow
  • MTBF/FIT estimates
  • Material content
  • Qualification summary
  • Ongoing reliability monitoring

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