DS2788E+ Maxim Integrated Products, DS2788E+ Datasheet

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... User EEPROM ♦ Unique ID and Multidrop 1-Wire ♦ 14-Pin TSSOP Package 14 LED3 13 LED4 12 LED5 PART PIO 11 DS2788E+ DS2788E+T& Denotes a lead(Pb)-free/RoHS-compliant package. 9 SNS T&R = Tape and reel. 8 VMA 1-Wire is a registered trademark of Maxim Integrated Products, Inc. Features ® Interface ...

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Stand-Alone Fuel-Gauge IC with LED Display Drivers ABSOLUTE MAXIMUM RATINGS Voltage Range on Any Pin Relative to V SS.............. Voltage Range VMA Relative ..................................................................... LED1–5.................................................................60mA each pin Stresses beyond ...

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ELECTRICAL CHARACTERISTICS: TEMPERATURE, VOLTAGE, CURRENT (V = 2.5V to 4.5V -25°C to +70°C, unless otherwise noted. Typical values are PARAMETER SYMBOL Temperature Resolution Temperature Error Voltage Resolution Voltage Full-Scale Voltage Error Current Resolution Current ...

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Stand-Alone Fuel-Gauge IC with LED Display Drivers ELECTRICAL CHARACTERISTICS: 1-Wire INTERFACE, OVERDRIVE (V = 2.5V to 4.5V -25°C to +70°C PARAMETER SYMBOL Time Slot Recovery Time Write-0 Low Time t Write-1 Low Time t Read Data ...

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PIN NAME 1 LED2 Display Driver. Connect to an LED connected LED1 Display Driver. Connect to an LED connected Display Ground. Ground connection for the LED display drivers. Connect ...

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Stand-Alone Fuel-Gauge IC with LED Display Drivers Detailed Description The DS2788 operates directly from 2.5V to 4.5V and supports single-cell Li+ battery packs. As shown in Figure 2, the DS2788 accommodates multicell applica- tions by adding a trim resistor for ...

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A PMOD SLEEP condition transi- tions back to ACTIVE mode when DQ is pulled high. The second option for entering SLEEP is an undervolt- age condition. When ...

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Stand-Alone Fuel-Gauge IC with LED Display Drivers Temperature Measurement The DS2788 uses an integrated temperature sensor to measure battery temperature with a resolution of 0.125°C. Temperature measurements are updated every 440ms and placed in the Temperature (TEMP) register in two’s ...

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Average Current Measurement The Average Current (IAVG) register reports an aver- age current level over the preceding 28 seconds. The register value is updated every 28s in two’s comple- ment form, and is the average of the eight preceding Current ...

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Stand-Alone Fuel-Gauge IC with LED Display Drivers current-sense resistors. RSGAIN is an 11-bit value stored in 2 bytes of the parameter EEPROM memory block. The RSGAIN value adjusts the gain from 0 to 1.999 in steps of 0.001 (precisely 2 ...

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ACRL MSB—ADDRESS 12h MSb “X”: reserved SNS 6.25μ SNS ±409.6mVh Figure 9. Fractional/Low Accumulated Current Register (ACRL) Format AB MSb “S”: SIGN ...

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... DS2788. Full and empty points are retrieved in a lookup process that retraces piece-wise linear model consisting of three curves CAPACITY LOOKUP AVAILABLE CAPACITY CALCULATION ACR HOUSEKEEPING AGE ESTIMATOR LEARN FUNCTION FuelPack is a trademark of Maxim Integrated Products, Inc. FULL FULL(T) (R) ACTIVE EMPTY AE(T) (R) STANDBY EMPTY SE(T) ...

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Each model curve is constructed with five line segments, numbered 1 through 5. Above +50°C, the segment 5 model curves extend infinitely with zero slope, approxi- mating the nearly flat change in capacity ...

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Stand-Alone Fuel-Gauge IC with LED Display Drivers Active Empty: The active empty curve defines the tem- perature variation in the empty point of the discharge profile based on a high-level load current (one that is sustained during a high-power operating ...

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Application Parameters In addition to cell model characteristics, several appli- cation parameters are needed to detect the full and empty points, as well as calculate results in mAh units. Sense Resistor Prime (RSNSP) RSNSP stores the value of the sense ...

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Stand-Alone Fuel-Gauge IC with LED Display Drivers continue uninterrupted until the battery is charged to full. Upon detecting full, LEARNF is cleared, the charge- to-full (CHGTF) flag is set, and the age scalar (AS) is adjusted according to the learned ...

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RAAC MSB—ADDRESS 02h MSb Figure 14. Remaining Active Absolute Capacity Register Format RSAC MSB—ADDRESS 04h Figure 15. Remaining Standby Absolute ...

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Stand-Alone Fuel-Gauge IC with LED Display Drivers RAAC [mAh] = (ACR[mVh] - AE(T) × FULL50[mVh]) × RSNSP [mhos] RSAC [mAh] = (ACR[mVh] - SE(T) × FULL50[mVh]) × RSNSP [mhos] RARC [%] = 100% × (ACR[mVh] - AE(T) × FULL50[mVh]) / ...

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All Control register bits are read and write accessible. The Control register is recalled from parameter EEPROM memory at power-up. Register bit values can ADDRESS 60h Field Bit Format NBEN 7 Read/Write UVEN 6 Read/Write PMOD 5 Read/Write RNAOP 4 ...

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Stand-Alone Fuel-Gauge IC with LED Display Drivers All Special Feature register bits are read and write acces- sible, with default values specified in each bit definition. ADDRESS 15h Field Bit Format Reserved 1:7 PIOSC 0 Read/Write Figure 20. Special Feature ...

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The EEPROM register provides access control of the EEPROM blocks. EEPROM blocks can be locked to pre- vent alteration of data within the block. Locking a block ADDRESS 1Fh Field Bit Format EEC 7 Read Only Read/Write LOCK 6 to ...

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Stand-Alone Fuel-Gauge IC with LED Display Drivers The DS2788 has a 256-byte linear memory space with registers for instrumentation, status, and control, as well as EEPROM memory blocks to store parameters and user information. Byte addresses designated as “Reserved” return ...

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Table 3. Memory Map (continued) ADDRESS (HEX) 12 ACRL: Low Accumulated Current Register MSB 13 ACRL: Low Accumulated Current Register LSB 14 AS: Age Scalar 15 SFR: Special Feature Register 16 FULL: Full Capacity MSB 17 FULL: Full Capacity LSB ...

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... Figure 24 bidirectional pin is not available on the bus master, separate output and input pins can be connected together. 48-BIT SERIAL NUMBER XOR XOR iButton is a registered trademark of Maxim Integrated Products, Inc. Hardware Configuration 8-BIT FAMILY CODE (32h) LSb INPUT LSb ...

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The 1-Wire bus must have a pullup resistor at the bus- master end of the bus. For short line lengths, the value of this resistor should be approximately 5kΩ. The idle state for the 1-Wire bus is high. If, for ...

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Stand-Alone Fuel-Gauge IC with LED Display Drivers Match Net Address [55h]. This command allows the bus master to specifically address one DS2788 on the 1-Wire bus. Only the addressed DS2788 responds to any subsequent function command. All other slave devices ...

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Copy Data [48h, XX]. This command copies the con- tents of the EEPROM shadow RAM to EEPROM cells for the EEPROM block containing address XX. Copy data commands that address locked blocks are ignored. While the copy data command is ...

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Stand-Alone Fuel-Gauge IC with LED Display Drivers NO 33h/39h READ MATCH YES MASTER Tx DS2788 Tx FAMILY CODE 1 BYTE DS2788 Tx SERIAL NUMBER BIT O 6 BYTES MATCH? DS2788 Tx CRC MASTER Tx 1 BYTE CLEAR RESUME MATCH? MASTER ...

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The 1-Wire bus requires strict signaling protocols to ensure data integrity. The four protocols used by the DS2788 are as follows: the initialization sequence (reset pulse followed by presence pulse), write-0, write-1, and read data. All these types of signaling ...

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Stand-Alone Fuel-Gauge IC with LED Display Drivers V PULLUP GND MIN MODE: 15μs STANDARD 2μs OVERDRIVE V PULLUP GND t RD LINE TYPE LEGEND: Figure 27. 1-Wire Write- and Read-Time Slots 30 ______________________________________________________________________________________ WRITE-0 SLOT t SLOT t t LOW0 ...

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PK+ 150Ω DATA 5.6V PK- For the latest package outline information and land patterns www.maxim-ic.com/packages. PACKAGE TYPE 14 TSSOP ______________________________________________________________________________________ Stand-Alone Fuel-Gauge IC with LED Display Drivers REGULATOR DISPLAY LED1 PIO V DD LED2 LED3 VMA LED4 V ...

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... Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. 32 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2009 Maxim Integrated Products DESCRIPTION Maxim is a registered trademark of Maxim Integrated Products, Inc ...