DS2784
1-Cell Stand-Alone Fuel Gauge IC with
Li+ Protector and SHA-1 Authentication
www.maxim-ic.com
GENERAL DESCRIPTION
FEATURES
The DS2784 operates from 2.5V to 4.6V for integration
in battery packs using a single lithium-ion (Li+) or Li+
polymer cell. Available capacity is reported in mAh and
as a percentage. Safe operation is ensured with the
included Li+ protection function and SHA-1-based
challenge-response authentication.
Precision Voltage, Temperature, and Current
Measurement System
Available Capacity Estimated from Coulomb
Count, Discharge Rate, Temperature, and Cell
Characteristics
Estimates Cell Aging Using Learn Cycles
Uses Low-Cost Sense Resistor
Precision measurements of voltage, temperature, and
current, along with cell characteristics and application
parameters are used to estimate capacity. The
available capacity registers report a conservative
estimate of the amount of charge that can be removed
given the current temperature and discharge rate.
Allows for Calibration of Gain and
Temperature Coefficient
Li+ Safety Circuitry—Overvoltage,
Undervoltage, Overcurrent, Short-Circuit
Protection
Programmable Safety Thresholds for
In addition to the nonvolatile (NV) storage for cell
compensation and application parameters, 16 bytes of
EEPROM memory is made available for the exclusive
use of the host system and/or pack manufacturer. This
facilitates battery lot and date tracking or NV storage of
system or battery usage statistics.
Overvoltage and Overcurrent
Authentication Using SHA-1 Algorithm and
64-Bit Secret
32-Byte Parameter EEPROM
16-Byte User EEPROM
A 1-Wire® interface provides serial communication at
16kbps or 143kbps to access data registers, control
registers, and user memory. Additionally, 1-Wire
communication enables challenge-response pack
authentication using SHA-1 as the hash algorithm in a
hash-based message authentication code (HMAC)
authentication protocol.
Dallas 1-Wire Interface with 64-Bit Unique ID
Tiny, Pb-Free, 14-Pin TDFN Package Embeds
Easily in Battery Packs Using Thin Prismatic
Cells
PIN CONFIGURATION
APPLICATIONS
Smartphones/PDAs
Digital Still and Video Cameras
Cordless VOIP Phones
Portable GPS Navigation
Modes and commands are capitalized for clarity.
1-Wire is a registered trademark of Dallas Semiconductor, a wholly
owned subsidiary of Maxim Integrated Products, Inc.
ORDERING INFORMATION
PART
DS2784G+
DS2784G+T&R
TEMP RANGE
-40°C to +85°C
-40°C to +85°C
TOP MARK
DS2784
DS2784
PIN PACKAGE
14 TDFN (3mm x 5mm)
14 TDFN (3mm x 5mm)
+ Denotes a lead-free package.
T&R = tape and reel
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REV: 071107