DS2784
General Description
The DS2784 operates from 2.5V to 4.6V for integration in battery packs using a single lithium-ion (Li+) or Li+ poly-mer 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 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.
In addition to the nonvolatile (NV) storage for cell compen-sation 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.
A 1-Wire? interface provides serial communication at 16kbps or 143kbps to access data registers, control registers, and user memory. Additionally, 1-Wire com-munication enables challenge-response pack authentica-tion using SHA-1 as the hash algorithm in a hash-based message authentication code (HMAC) authentication protocol.
Applications
●Health and Fitness Monitors
●Digital Still, Video, and Action Cameras●Medical Devices
●Handheld Computers and Terminals●Handheld Radios
●Home and Building Automation, Sensors●Smart Batteries●
Power Tools
Ordering Information appears at end of data sheet.
Modes and commands are capitalized for clarity.
1-Wire is a registered trademark of Maxim Integrated Products,Inc.
1-Cell Fuel Gauge with FuelPack,Protector, and SHA-1 Authentication
Features
●Precision Voltage, Temperature, and Current
Measurement System●Available Capacity Estimated from Coulomb
Count, Discharge Rate, Temperature, and CellCharacteristics●Estimates Cell Aging Using Learn Cycles●Uses Low-Cost Sense Resistor
●Allows for Calibration of Gain and Temperature
Coefficient●Li+ Safety Circuitry—Overvoltage, Undervoltage,
Overcurrent, Short-Circuit Protection●Programmable Safety Thresholds for Overvoltage
and Overcurrent●Authentication Using SHA-1 Algorithm and 64-Bit
Secret●32-Byte Parameter EEPROM●16-Byte User EEPROM
●Maxim 1-Wire Interface with 64-Bit Unique ID●Tiny, Pb-Free, 14-Pin TDFN Package Embeds Easily
in Battery Packs Using Thin Prismatic Cells
Simple Fuel Gauge Circuit DiagramPK+1K1K1K1501KPLSDCCCVDDDATA150DQDS2784VINCPPIOCTGSNSVSS5.1VRSNS0.1μF0.1μFPK-DS2784
1-Cell Fuel Gauge with FuelPack,Protector, and SHA-1 Authentication
Absolute Maximum Ratings
Voltage Range on PLS Pin Relative to VSS..........-0.3V to +18VVoltage Range on CP Pin Relative to VSS ...........-0.3V to +12VVoltage Range on DC
Pin Relative to VSS...............................-0.3V to (VCP + 0.3V)Voltage Range on CC
Pin Relative to VSS.........................VDD - 0.3V to VCP + 0.3VVoltage Range on All
Other Pins Relative to VSS...............................-0.3V to +6.0V
Maximum Voltage Range on
VIN Pin Relative to VDD........................................VDD + 0.3VContinuous Sink Current, PIO, DQ ....................................20mAContinuous Sink Current, CC, DC......................................10mAOperating Temperature Range ...........................-40°C to +85°CStorage Temperature Range ............................-55°C to +125°CLead Temperature (soldering,10s) ..................................±300°CSoldering Temperature (reflow) .......................................+260°C
This is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the operation sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods of time may affect reliability.
Electrical Characteristics
(VDD = 2.5V to 4.6V, TA = -20°C to +70°C, unless otherwise noted. Typical values are at TA = +25°C.)
PARAMETER
Supply Voltage
SYMBOLVDDIDD0
Supply Current
IDD1IDD2IDD3
Temperature AccuracyTemperature ResolutionTemperature RangeVoltage Accuracy, VINVoltage Resolution, VINVoltage Range, VINInput Resistance, VINCurrent ResolutionCurrent Full ScaleCurrent Gain ErrorCurrent Offset
Accumulated Current OffsetTime Base ErrorCP Output VoltageCP Startup TimeOutput High: CC, DCOutput Low: CC
VCPtSCPVOHCCVOHDCVOLCC
(Notes 2, 3, 4)(Notes 2, 3, 4)0°C ≤ TA ≤ +50°CICC + IDC = 0.9μA
CE = 0, DE = 0, CCP = 0.1μF, Active mode
-51.2-1-15-360-2-38.50VCP - 0.4
VDD + 0.1
9.25
015
1.56
+51.2+1+250+2+310.00200
4.0 ≤ VIN ≤ 4.6, VIN ≤ VDD + 0.3V2.5 ≤ VIN ≤ 4.6V, VIN ≤ VDD + 0.3V
-128.000-30-50
4.88
4.6
(Note 1)Sleep mode
Sleep mode, VDD = 2.5V 0°C to +50°CActive mode
Active mode during SHA computation
-3
0.125
+127.875
30+50
CONDITIONS
MIN+2.5
10.485300TYP
MAX+4.641.5125500+3
°C°C°CmVmVVM?μVmV% full scaleμVμVh/day%VmsVVμAUNITSV
IOH = -100μA (Note 5)IOL = 100μA
DS2784
1-Cell Fuel Gauge with FuelPack,Protector, and SHA-1 Authentication
Electrical Characteristics (continued)
(VDD = 2.5V to 4.6V, TA = -20°C to +70°C, unless otherwise noted. Typical values are at TA = +25°C.)
PARAMETER
Output Low: DCDQ, PIO Voltage RangeDQ, PIO Input-Logic HighDQ, PIO Input-Logic LowDQ, PIO Output-Logic LowDQ, PIO Pullup CurrentDQ, PIO Pulldown CurrentDQ Input CapacitanceDQ Sleep TimeoutPIO, DQ Wake DebounceSHA-1 COMPUTATION TIMING Computation Time
VIHVILVOLIPUIPDCDQtSLEEPtWDB
VDQ < VILSleep mode
2
100
30
IOL = 4mA
Sleep mode, VPIN = VDD - 0.4VActive mode, VPIN = 0.4V
0.20.250
9
SYMBOLVOLDC
IOL = 100μA
-0.31.5
0.60.4
CONDITIONS
MIN
TYP
MAX0.1+5.5
UNITSVVVVVμAμApFsmsms
tSHAElectrical Characteristics: Protection Circuit
(VDD = 2.5V to 4.6V, TA = 0°C to +50°C, unless otherwise noted. Typical values are at TA = +25°C.)
PARAMETER
Overvoltage DetectCharge-Enable VoltageUndervoltage DetectOvercurrent Detect: ChargeOvercurrent Detect: Discharge
Short-Circuit Current DetectOvervoltage DelayUndervoltage DelayOvercurrent DelayShort-Circuit DelayTest ThresholdTest Current
PLS Pulldown CurrentRecovery Current
SYMBOLVOVVCEVUVVCOCVDOCVSCtOVDtUVDtOCDtSCDVTPITSTIPPDIRC
COC, DOC conditionsSC, COC, DOC conditionSleep mode
VUV condition, max: VPLS = 15V,
VDD = 1V min: VPLS = 4.2V, VDD = 2V OC = 11bOC = 00bOC = 11bOC = 00bSC = 1bSC = 0b(Note 6)(Notes 6, 7)VOV = 11000bVOV = 00011bRelative to VOVCONDITIONS
MIN4.457 4.252-752.40-57-15.57623.5240120425848800.310302.5
101200.8202005.0TYP4.4824.277-1002.45-72-23.59635.5300150
MAX4.5074.302-1252.50-87-31.511647.53601801150680121601.54060010.00
UNITSVmVVmVmVmVmsmsmsμsVμAμAmA
DS2784
1-Cell Fuel Gauge with FuelPack,Protector, and SHA-1 Authentication
EEPROM Reliability Specification
(VDD = 2.5V to 4.6V, TA = -20°C to +70°C, unless otherwise noted.)
PARAMETER
EEPROM Copy TimeEEPROM Copy Endurance
SYMBOLtEECNEECTA = +50°C
50,000
CONDITIONS
MIN
TYP
MAX10
UNITSmscycles
Electrical Characteristics: 1-Wire Interface, Standard
(VDD = 2.5V to 4.6V, TA = -20°C to +70°C, unless otherwise noted.)
PARAMETER
Time SlotRecovery TimeWrite-0 Low TimeWrite-1 Low TimeRead-Data ValidReset-Time HighReset-Time LowPresence-Detect HighPresence-Detect Low
SYMBOLtSLOTtRECtLOW0tLOW1tRDVtRSTHtRSTLtPDHtPDL
4804801560
96060240
CONDITIONS
MIN601601
1201515
TYP
MAX120
UNITSμsμsμsμsμsμsμsμsμs
DS2784
Typical Operating Characteristics
1-Cell Fuel Gauge with FuelPack,Protector, and SHA-1 Authentication
MEMORY存储芯片DS2784G+T&R中文规格书 - 图文
