Document
DS2781 1-Cell or 2-Cell Stand-Alone
Fuel Gauge IC
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 onchip 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
SIMPLIFIED TYPICAL OPERATING CIRCUIT
P+
DS2781
DQ DQ VDD
PIO VIN
OVD
VB
SNS
VSS
P- Protection Circuit
ORDERING INFORMATION
PART
PIN-PACKAGE
DS2781E+
8 TSSOP
DS2781E+T&R
8 TSSOP
DS2781G+
10 TDFN-EP*
DS2781G+T&R
10 TDFN-EP*
+Denotes a lead-free/RoHS-compliant package.
T&R = Tape and reel.
*EP = Exposed pad.
1-Wire is a registered trademark of Maxim Integrated Products, Inc.
PIN CONFIGURATIONS
TOP VIEW
VB VSS
VIN VDD
TSSOP-8
PIO SNS
OVD
DQ
VB VSS VSS VIN
VDD
PAD
PIO SNS
NC
OVD DQ
3mm x 4mm TDFN-10
FEATURES
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
TOP MARK
2781 2781 2781 2781
1 of 31
REV: 062708
DS2781
ABSOLUTE MAXIMUM RATINGS
Voltage Range on VDD, VIN Relative to VSS Voltage Range on Any Pin Relative to VSS Continuous Sink Current, DQ, PIO Operating Temperature Range Storage Temperature Range Soldering Temperature
-0.3V to +12V
-0.3V to +6.0V 20mA
-40°C to +85°C -55°C to +125°C Refer to the IPC/JEDEC J-STD-020 Specification.
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to the absolute maximum rating conditions for extended periods may affect device reliability.
RECOMMENDED DC OPERATING CHARACTERISTICS
(VDD = 2.5V to 10V, TA = -20°C to +70°C, unless otherwise noted. Typical values are at TA = +25°C)
PARAMETER
SYMBOL CONDITIONS
MIN
TYP
MAX
Supply Voltage VIN Voltage Range DQ, PIO Voltage Range
VB Output Voltage
OVD Voltage Range
VDD (Note 1) (Note 1)
(Note 1) VDD > 3.0V, VVB IVB = 500μA, (Note 1) (Note 1)
+2.5 -0.3 -0.3
2.5
-0.3
+10 VDD + 0.3
+5.5
2.8 3.1
VVB + 0.3
UNITS V V V
V
V
DC ELECTRICAL CHARACTERISTICS
(VDD = 2.5V to 10V, TA = -20°C to +70°C, unless otherwise noted. Typical values are at TA = +25°C.)
PARAMETER
SYMBOL
CONDITIONS
MIN TYP
MAX
ACTIVE Current
SLEEP Mode Current
Input Logic-High:DQ, PIO Input Logic-Low: DQ, PIO Output Logic-Low: DQ, PIO Pulldown Current: DQ, PIO Input Logic-High: OVD Input Logic-Low: OVD VIN Input Resistance DQ Capacitance DQ SLEEP Timeout Undervoltage SLEEP Threshold
IACTIVE
ISLEEP
VIH VIL VOL IPD VIH VIL RIN CDQ tSLEEP
VSLEEP
IVB = 0
TA > +50°C, IVB = 0
IVB = 0, (Note 5)
(Note 1) (Note 1) IOL = 4mA (Note 1) VDQ, VPIO = 0.4V (Note 1) (Note 1)
(Note 4) DQ < VIL UVTH = 1, (Note 1) UVTH = 0, (Note 1)
70
3 1.5
VVB - 0.2
15
1.5 4.8 2.40
0.2
50 2 4.9 2.45
95 10 5
0.6 0.4
VSS + 0.2
2.5 5.0 2.50
UNITS
μA
μA
V V V μA V V MΩ pF s
V
ELECTRICAL CHARACTERISTICS: TEMPERATURE, VOLTAGE, CURRENT
(VDD = 2.5V to 10V, TA = -20°C to +70°C, unless otherwise noted. Typical values are at TA = +25°C.)
PARAMETER
SYMBOL
CONDITIONS
MIN TYP MAX
Temperature Resolution Temperature Error Voltage Resolution
TLSB TERR VLSB
0.125 9.76
±3
2 of 31
UNITS °C °C mV
DS2781
PARAMETER Voltage Full-Scale Voltage Error Current Resolution Current Full-Scale Current Gain Error Current Offset Error
Accumulated Current Offset
Timebase Error
SYMBOL VFS VERR ILSB IFS IGERR
IOERR
qOERR
tERR
CONDITIONS
(Note 2) 0°C ≤ TA ≤ +70°C, (Note 4) 0°C ≤ TA ≤ +70°C, VSNS = VSS (Notes 3, 4) TA = +25°C, VDD = 7.6V
MIN 0
- 7.82 - 188
TYP 1.56
MAX 9.9902 ±100
±51.2 ±1
+ 12.5 +0 ±1 ±2
UNITS
V mV µV mV % FullScale μV μVhr/ day
%
ELECTRICAL CHARACTERISTICS: 1-WIRE INTERFACE, STANDARD
(VDD = 2.5V to 10V, TA = -20°C to +70°C.)
PARAMETER
SYMBOL
CONDITIONS
MIN TYP MAX
Time Slot Recovery Time Write-0 .