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BQ27427 ACTIVE Single-cell battery fuel gauge with pre-programmed chemistry and integrated sense resistor Low power consumption, internal sense resistor and battery state-of-health (aging) estimates

Product details

Cell chemistry Li-Ion/Li-Polymer Number of series cells Single Cell Communication interface I2C Battery capacity (min) (mAh) 100 Battery capacity (max) (mAh) 8000 Implementation System External capacity indication None Features Impedance Track™ algorithm, Integrated Sense Resistor Operating temperature range (°C) -40 to 85 Rating Catalog
Cell chemistry Li-Ion/Li-Polymer Number of series cells Single Cell Communication interface I2C Battery capacity (min) (mAh) 100 Battery capacity (max) (mAh) 8000 Implementation System External capacity indication None Features Impedance Track™ algorithm, Integrated Sense Resistor Operating temperature range (°C) -40 to 85 Rating Catalog
DSBGA (YZF) 9 3.0625 mm² 1.75 x 1.75
  • Single-Cell Li-Ion Battery Fuel Gauge
    • Resides on System Board
    • Supports Embedded or Removable Batteries
    • Powered Directly from Battery with Integrated
      LDO
    • Low-Value Integrated Sense Resistor
      (7 mΩ, Typical)
  • Easy-to-Configure Fuel Gauging Based on
    Patented Impedance Track™ Technology
    • Reports Remaining Capacity and State-of-
      Charge (SOC) with Smoothing Filter
    • Automatically Adjusts for Battery Aging, Self-
      Discharge, Temperature, and Rate Changes
    • Battery State-of-Health (Aging) Estimation
  • Microcontroller Peripheral Supports:
    • 400-kHz I2C Serial Interface
    • Configurable SOC Interrupt or
      Battery Low Digital Output Warning
    • Internal Temperature Sensor or
      Host-Reported Temperature
  • Single-Cell Li-Ion Battery Fuel Gauge
    • Resides on System Board
    • Supports Embedded or Removable Batteries
    • Powered Directly from Battery with Integrated
      LDO
    • Low-Value Integrated Sense Resistor
      (7 mΩ, Typical)
  • Easy-to-Configure Fuel Gauging Based on
    Patented Impedance Track™ Technology
    • Reports Remaining Capacity and State-of-
      Charge (SOC) with Smoothing Filter
    • Automatically Adjusts for Battery Aging, Self-
      Discharge, Temperature, and Rate Changes
    • Battery State-of-Health (Aging) Estimation
  • Microcontroller Peripheral Supports:
    • 400-kHz I2C Serial Interface
    • Configurable SOC Interrupt or
      Battery Low Digital Output Warning
    • Internal Temperature Sensor or
      Host-Reported Temperature

The Texas Instruments bq27421-G1 fuel gauge is a minimally configured microcontroller peripheral that provides system-side fuel gauging for single-cell Li-Ion batteries. The device requires very little user configuration and system microcontroller firmware development.

The bq27421-G1 fuel gauge uses the patented Impedance TrackTM algorithm for fuel gauging, and provides information such as remaining battery capacity (mAh), state-of-charge (%), and battery voltage (mV).

Battery fuel gauging with the bq27421-G1 fuel gauge requires connections only to PACK+ (P+) and PACK– (P–) for a removable battery pack or embedded battery circuit. The tiny 9-ball, 1.62 mm × 1.58 mm, 0.5-mm pitch NanoFree™ chip scale package (DSBGA) is ideal for space-constrained applications.

The Texas Instruments bq27421-G1 fuel gauge is a minimally configured microcontroller peripheral that provides system-side fuel gauging for single-cell Li-Ion batteries. The device requires very little user configuration and system microcontroller firmware development.

The bq27421-G1 fuel gauge uses the patented Impedance TrackTM algorithm for fuel gauging, and provides information such as remaining battery capacity (mAh), state-of-charge (%), and battery voltage (mV).

Battery fuel gauging with the bq27421-G1 fuel gauge requires connections only to PACK+ (P+) and PACK– (P–) for a removable battery pack or embedded battery circuit. The tiny 9-ball, 1.62 mm × 1.58 mm, 0.5-mm pitch NanoFree™ chip scale package (DSBGA) is ideal for space-constrained applications.

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Technical documentation

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Type Title Date
* Data sheet bq27421-G1 System-Side Impedance Track Fuel Gauge With Integrated Sense Resistor datasheet (Rev. E) PDF | HTML 06 Jan 2016
* User guide bq27421-G1 Technical Reference Manual (Rev. C) 30 Aug 2016
White paper Understanding Functional Safety FIT Base Failure Rate Estimates per IEC 62380 and SN 29500 (Rev. A) PDF | HTML 30 Apr 2024
Technical article Get smart: How intelligent battery gauges improve battery life in continuous gluco PDF | HTML 19 Apr 2019
Application note Achieving The Successful Learning Cycle 19 Jun 2018
Application note Simple Guide to Chemical ID Selection Tool (GPC) (Rev. A) 05 Jun 2018
Application note Gauge Communication 12 Jan 2017
Application note Theory and Implementation of Impedance Track Battery Fuel-Gauging Algorithm (Rev. A) PDF | HTML 16 May 2014
More literature Quickstart Guide for bq27421-G1 (Rev. B) 06 May 2014
Application note Verification and Accuracy Test Methods of Gas Gauges 05 Jun 2013
Application note Going to Production With the bq274xx Family of Gas Gauges 27 Jun 2011

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