1FEATURES
2• Next Generation Patented Impedance Track™
Technology Accurately Measures Available
Charge in Li-Ion and Li-Polymer Batteries
– Better Than 1% Error Over the Lifetime of
the Battery
• Supports the Smart Battery Specification
SBS V1.1
• Flexible Configuration for 2-Series, 3-Series,
and 4-Series Cell Li-Ion and Li-Polymer
Batteries
• Powerful 8-Bit RISC CPU With Ultralow Power
Modes
• Full Array of Programmable Protection
Features
– Voltage, Current, and Temperature
• Complies with JEITA Guidelines
• Added Flexibility to Handle More Complex
Charging Profiles
• Lifetime Data Logging
• Supports SHA-1 Authentication
• Available in 20-Pin TSSOP (PW) and 32-Pin
QFN (RSM) Packages

APPLICATIONS
• Notebook PCs
• Medical and Test Equipment
• Portable Instrumentation

DESCRIPTION
The bq20z40-R1 SBS-compliant gas gauge and
protection IC, incorporating patented Impedance
Track™ technology, is designed for battery-pack or
in-system installation. The bq20z40-R1 measures and maintains an accurate record of available charge
in Li-Ion or Li-Polymer batteries using its integrated
high-performance analog peripherals. The
bq20z40-R1 monitors capacity change, battery
impedance, open-circuit voltage, and other critical
parameters of the battery pack, and reports the
information to the system host controller over a
serial-communication bus. It is designed to work with
the bq29330 analog front-end (AFE) protection IC to
maximize functionality and safety, while minimizing
external component count and cost in smart battery
circuits.
The Impedance Track™ technology continuously analyzes the battery impedance, resulting in superior
gas-gauging accuracy. This enables the remaining
capacity to be calculated with discharge rate,
temperature, and cell aging, which are all accounted
for during each stage of every cycle.