1.1 FEATURES

12• Comprehensive Battery Fuel Gauge for Single

Cell and 1-Series Li-Ion/Li-Polymer

Applications

• Secure Battery Authentication Using

SHA-1/HMAC Encryption

• Calculates and Reports

– Remaining Battery Capacity

– Battery Voltage and Temperature

– Charge and Discharge Current

– Four Time-to-Empty Predictions

• Battery Fuel Gauge Based on Patented

Impedance Track™ Technology

– Models the Battery Discharge Curve for

Accurate Time-to-Empty Predictions

– Automatically Adjusts for Battery Aging,

Battery Self Discharge, and

Temperature/Rate Inefficiencies

– Low Value Sense Resistor (10mΩ or Less)

• 96-Bytes Non-Volatile Scratch Pad Data

Memory

• I2C Communications Interface to the Host

• 20-Pin TSSOP Package

1.2 APPLICATIONS

• POS Terminals

• Industrial Data Collection

• Smartphones

• PDAs

• Digital Cameras

• Handheld Terminals

1.3 DESCRIPTION

The Texas Instruments’ bq27350 is a battery fuel

gauge with secure authentication support for single

cell Li-Ion/Li-Polymer battery packs. Designed for

battery pack integration, the device requires little host

microcontroller firmware support for implementation.

The system host processor communicates with the

bq27350 over an I2C interface to obtain remaining

battery capacity, system run-time predictions, and

other critical battery information.

The bq27350 uses the patented Impedance Track™

algorithm for its fuel gauging. The gauge provides

information such as state-of-charge (%), run-time to

empty (min.), charge time to full (min.), battery

voltage (V), and pack temperature (°C).

The bq27350 also features both integrated and

external support for secure battery pack

authentication, using the SHA-1/HMAC authentication

algorithm.