BQ27441-G1 Datasheet, PDF (9/22 Pages) Texas Instruments – System-Side Impedance Track Fuel Gauge

bq27441-G1
www.ti.com
SLUSBH1A – NOVEMBER 2013 – REVISED JANUARY 2014
GENERAL DESCRIPTION
The bq27441-G1 accurately predicts the battery capacity and other operational characteristics of a single Li-
based rechargeable cell. It can be interrogated by a system processor to provide cell information, such as state-
of-charge (SOC).
Information is accessed through a series of commands, called Standard Commands. Further capabilities are
provided by the additional Extended Commands set. Both sets of commands, indicated by the general format
Command( ), are used to read and write information contained within the bq27441-G1 control and status
registers, as well as its data locations. Commands are sent from system to gauge using the bq27441-G1’s I²C
serial communications engine, and can be executed during application development, system manufacture, or
end-equipment operation.
The key to the bq27441-G1’s high-accuracy gas gauging prediction is Texas Instrument’s proprietary Impedance
Track™ algorithm. This algorithm uses cell measurements, characteristics, and properties to create state-of-
charge predictions that can achieve high accuracy across a wide variety of operating conditions and over the
lifetime of the battery.
The bq27441-G1 measures charge/discharge activity by monitoring the voltage across a small-value sense
resistor. When a cell is attached to the bq27441-G1, cell impedance is computed, based on cell current, cell
open-circuit voltage (OCV), and cell voltage under loading conditions.
The bq27441-G1 uses an integrated temperature sensor for estimating cell temperature. Alternatively, the host
processor can provide temperature data for the bq27441-G1.
To minimize power consumption, the bq27441-G1 has several power modes: INITIALIZATION, NORMAL,
SLEEP, and HIBERNATE. The bq27441-G1 passes automatically between these modes, depending upon the
occurrence of specific events, though a system processor can initiate some of these modes directly. More details
are found in the bq27441-G1 Technical Reference Manual (SLUUAC9).
NOTE
Formatting Conventions in this Document:
Commands: italics with parentheses( ) and no breaking spaces, for example,
RemainingCapacity( ).
Data Flash: italics, bold, and breaking spaces, for example, Design Capacity.
Register bits and flags: italics with brackets [ ], for example, [TDA]
Data flash bits: italics, bold, and brackets [ ], for example, [LED1]
Modes and states: ALL CAPITALS, for example, UNSEALED mode.
Copyright © 2013–2014, Texas Instruments Incorporated
Product Folder Links: bq27441-G1
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