Rainbow Electronics DS2781 - Manual

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GENERAL DESCRIPTION
The DS2781 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.
APPLICATIONS
Digital Video Cameras
Commercial Two-Way Radios
Industrial PDAs and Handheld PC Data Terminals
Portable GPS Navigation Systems
TYPICAL OPERATING CIRCUIT
FEATURES
§ Precision Voltage, Temperature, and Current
Measurement System
§ Operates in One-Cell or Two--Cell Applications
§ Accurate, Temperature Stable Internal Time
Base
§ 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 Tempco Calibration Allows the Use of
Low-Cost Sense Resistors
§ 24-Byte Battery/Application Parameter EEPROM
§ 16-Byte User EEPROM
§ Unique ID and Multidrop 1-Wire Ò Interface
§ Tiny 8-Pin TSSOP Package Embeds Easily in
Battery Packs Using Thin Prismatic Cells
PIN CONFIGURATION
DQ
SNS
VDD
VSS
P+
P-
DQ
Protection
Circuit
DS2781
PIO
VB
VIN
OVD
ORDERING INFORMATION
PART MARKING PACKAGE
DS2781E+ 2781 TSSOP
DS2781E+T&R 2781 Tape-and-Reel
+ Denotes lead-free package.
1-Wire is a registered trademark of Dallas Semiconductor.
TOP VIEW
1
2
3
4 5
6
7
8 VB
VSS
VIN
VPLS
PIO
SNS
OVD
DQ
TSSOP-8
DS2781
1-Cell or 2-Cell
Standalone Fuel Gauge IC