1 Features

• Single-series cell Li-ion battery fuel gauge resides

on system board

– Integrated 2.5 VDC LDO

– External low-value 10-mΩ sense resistor

• Patented Impedance Track™ technology

– Adjusts for battery aging, self-discharge,

temperature, and rate changes

– Reports remaining capacity, state-of-charge

(SOC), and time-to-empty

– Optional smoothing filter

– Battery state-of-health (aging) estimation

– Supports embedded or removable packs with

up to 14500-mAh capacity

– Accommodates pack swapping with two

separate battery profiles

• Microcontroller peripheral supports

– 400-kHz I2C serial interface

– 32 bytes of scratch-pad FLASH NVM

– Battery low digital output warning

– Configurable SOC interrupts

– External thermistor, internal sensor, or hostreported

temperature options

• Tiny 15-pin, 2610 × 1956 μm, 0.5-mm pitch

NanoFree™ (DSBGA) package

2 Applications

• Smartphones, feature phones, and tablets

• Digital still and video cameras

• Handheld terminals

• MP3 or multimedia players

3 Description

The Texas Instruments BQ27520-G4 system-side Liion

battery fuel gauge is a microcontroller peripheral

that provides fuel gauging for single-cell Li-ion

battery packs. The device requires little system

microcontroller firmware development. The fuel gauge

resides on the main board of the system and

manages an embedded battery (non-removable) or a

removable battery pack.

The fuel gauge uses the patented Impedance Track™

algorithm for fuel gauging, and provides information

such as remaining battery capacity (mAh), state-ofcharge

(%), run-time to empty (minimum), battery

voltage (mV), temperature (°C), and state of health

(%).

Battery fuel gauging requires only PACK+ (P+),

PACK– (P–), and optional Thermistor (T) connections

to a removable battery pack or embedded battery

circuit. The device uses a 15-ball NanoFree™

(DSBGA) package in the nominal dimensions of

2610 × 1956 μm with 0.5-mm lead pitch. It is ideal for

space-constrained applications.