DS2782G+T&R Maxim Integrated Products, DS2782G+T&R Datasheet
DS2782G+T&R
Specifications of DS2782G+T&R
Related parts for DS2782G+T&R
DS2782G+T&R Summary of contents
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GENERAL DESCRIPTION The DS2782 measures voltage, temperature and current, and estimates available rechargeable lithium ion and lithium-ion polymer batteries. Cell characteristics parameters used in the calculations are stored in on- chip EEPROM. The available capacity registers report ...
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ABSOLUTE MAXIMUM RATINGS Voltage Range on Any Pin Relative to V Voltage Range on V Relative Operating Temperature Range Storage Temperature Range Soldering Temperature Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to ...
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PARAMETER Current Gain Error Current Offset Error Accumulated Current Offset Time-Base Error ELECTRICAL CHARACTERISTICS: 2-WIRE INTERFACE (2.5V V 4.5V -20C to +70C PARAMETER SCL Clock Frequency Bus Free Time Between a STOP and START ...
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Note 1: All voltages are referenced to V Note 2: To properly enter sleep mode the application should hold the bus low for longer than the maximum t Note 3: Factory calibrated accuracy. Higher accuracy can be achieved by in-system ...
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PIN DESCRIPTION PIN NAME TSSOP TDFN- N. VSS 3 4 VIN SDA 6 7 SCL — SNS 8 10 PIO — Figure 2. ...
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DETAILED DESCRIPTION The DS2782 operates directly from 2.5V to 4.5V and supports single cell Lithium-ion battery packs. As shown in Figure 3, the DS2782 accommodates multicell applications by adding a voltage regulator for VDD and voltage divider for VIN. Nonvolatile ...
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POWER MODES The DS2782 has two power modes: ACTIVE and SLEEP. On initial power up, the DS2782 defaults to ACTIVE mode. While in ACTIVE mode, the DS2782 is fully functional with measurements and capacity estimation continuously updated. In SLEEP mode, ...
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VIN is usually connected to the positive terminal of a single cell Lithium-Ion battery via a 1k resistor. The input impedance is sufficiently large (15M connected to a high impedance voltage divider in order to support multiple cell ...
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AVERAGE CURRENT MEASUREMENT The Average Current register reports an average current level over the preceding 28 seconds. The register value is updated every 28s in two’s complement form, and is the average of the 8 preceding Current register updates. The ...
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CURRENT ACCUMULATION Current measurements are internally summed, or accumulated, at the completion of each conversion period with the results displayed in the Accumulated Current Register (ACR). The accuracy of the ACR is dependent on both the current measurement and the ...
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Figure 9. Fractional/Low Accumulated Current Register Format, ACRL ACRL MSB—Address 12h MSb “X”: reserved VSS - VSNS 6.25Vh VSS - VSNS 409.6mVh ACCUMULATION BIAS The Accumulation Bias register (AB) allows an arbitrary ...
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CAPACITY ESTIMATION ALGORITHM Remaining capacity estimation uses real-time measured values and stored parameters describing the cell characteristics and application operating limits. The following diagram describes the algorithm inputs and outputs. Figure 11. Top-Level Algorithm Diagram ...
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... Standby Empty: The Standby Empty curve defines the temperature variation in the empty point in the discharge defined by the application standby current and the minimum voltage required for standby operation. In typical PDA FuelPack is a trademark of Maxim Integrated Products, Inc. FULL Active Empty ...
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Standby Empty represents the point that the battery can no longer support RAM refresh and thus the standby voltage is set by the RAM voltage supply requirements. In other applications, Standby Empty can represent the point that the battery ...
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APPLICATION PARAMETERS In addition to cell model characteristics, several application 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 resistor ...
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CAPACITY ESTIMATION UTILITY FUNCTIONS Aging Estimation As discussed above, the AS register value is adjusted occasionally based on cumulative discharge. As the ACR register decrements during each discharge cycle, an internal counter is incremented until equal to 32 times AC. ...
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RESULT REGISTERS The DS2782 processes measurement and cell characteristics on a 3.5s interval and yields seven result registers. The result registers are sufficient for direct display to the user in most applications. The host system can produce customized values for ...
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Remaining Active Relative Capacity (RARC) [%]: RARC reports the capacity available under the current temperature conditions at the Active Empty discharge rate (IAE) to the Active Empty point in relative units of percent. RARC is 8 bits. See Figure 16. ...
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STATUS REGISTER The STATUS register contains bits which report the device status. The bits can be set internally by the DS2782. The CHGTF, AEF, SEF, LEARNF and VER bits are read only bits which can be cleared by hardware. The ...
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CONTROL REGISTER 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 be modified in shadow RAM after power-up. Shadow RAM values can be saved as ...
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EEPROM REGISTER The EEPROM register provides access control of the EEPROM blocks. EEPROM blocks can be locked to prevent alteration of data within the block. Locking a block disables write access to the block. Once a block is locked, it ...
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MEMORY The DS2782 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 undefined data when read. Reserved ...
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Table 2. Memory Map ADDRESS (HEX) 00 Reserved 01 STATUS - Status Register 02 RAAC - Remaining Active Absolute Capacity MSB 03 RAAC - Remaining Active Absolute Capacity LSB 04 RSAC - Remaining Standby Absolute Capacity MSB 05 RSAC - ...
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Table 3. Parameter EEPROM Memory Block 1 ADDRESS DESCRIPTION (HEX) 60 CONTROL - Control Register Accumulation Bias Aging Capacity MSB Aging Capacity LSB 64 VCHG - Charge Voltage 65 IMIN - ...
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Acknowledge Bits Each byte of a data transfer is acknowledged with an Acknowledge bit ( Acknowledge bit (N). Both the master and the DS2782 slave generate acknowledge bits. To generate an Acknowledge, the receiving device must pull ...
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Basic Transaction Formats Write: S SAddr W A MAddr A Data0 write transaction transfers one or more data bytes to the DS2782. The data transfer begins at the memory address supplied in the MAddr byte. Control of ...
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Table 5. Function Commands TARGET FUNCTION EEPROM COMMAND BLOCK 0 Copy Data 1 0 Recall Data 1 0 Lock 1 64-BIT UNIQUE ID The DS2782 can be special ordered with a unique, factory-programmed ID that is 64 bits in length. ...
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... No circuit patent licenses are implied. Maxim/Dallas Semiconductor reserves the right to change the circuitry and specifications without notice at any time The Maxim logo is a registered trademark of Maxim Integrated Products, Inc. The Dallas logo is a registered trademark of Dallas Semiconductor Corporation. DESCRIPTION maximum operating range in the voltage” ...