The DS2781K remains in production, however, for new projects, we recommend ModelGauge m5 MAX17215 fuel gauge.
The DS2781K measures voltage, temperature, and current, and estimates available capacity for rechargeable Lithium-Ion and Lithium-Ion Polymer batteries. Cell stack characteristics and application parameters used in the calculations are stored in on-chip EEPROM. The available capacity registers report a conservative estimate of the amount of charge that can be removed given the current temperature, discharge rate, stored charge and application parameters. Capacity estimation is reported in milliamp hours remaining and percentage of full.
Feature
Precision Voltage, Temperature, and Current Measurement System
Operates in One-Cell or Two--Cell Applications
Accurate, Temperature Stable Internal Timebase
Absolute and Relative Capacity Estimated from Coulomb Count, Discharge Rate, Temperature, and Battery Cell Characteristics
Accurate Warning of Low Battery Conditions
Automatic Backup of Coulomb Count and Age Estimation to Nonvolatile (NV) EEPROM
Gain and Temperature Coefficient Calibration Allows the Use of Low-Cost Sense Resistors
24-Byte Parameter EEPROM
16-Byte User EEPROM
Unique ID and Multidrop 1-Wire? Interface
Tiny 8-Pin TSSOP and 10-Pin TDFN (3mm x 4mm) Packages Embed Easily in Thin Prismatic Cell Packs
Applications
Commercial Two-Way Radios
Digital Video Cameras
Industrial PDAs and Handheld PC Data Terminals
Portable GPS Navigation Systems
Catalogue
FPGA / CPLD
Memory
MOS 
MCU 
DSP
OCEP
Secondary 
Other 
