DS2786BG+T&R Maxim Integrated Products, DS2786BG+T&R Datasheet
DS2786BG+T&R
Specifications of DS2786BG+T&R
Related parts for DS2786BG+T&R
DS2786BG+T&R Summary of contents
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... Digital Still Cameras Digital Audio (MP3) Players Li+ PROTECTION CIRCUIT ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. ♦ Relative Capacity Calculated from Combination Coulomb Counter and Open-Circuit Cell Voltage (OCV) Battery Model ♦ ...
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Stand-Alone OCV-Based Fuel Gauge ABSOLUTE MAXIMUM RATINGS Voltage on All Pins Except V Relative to V PROG Voltage on V Relative to V ..........................-0.3V to +18V PROG SS Operating Temperature Range ...........................-40°C to +85°C Stresses beyond those listed under “Absolute ...
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Stand-Alone OCV-Based Fuel Gauge DC ELECTRICAL CHARACTERISTICS (continued) (2.5V ≤ V ≤ 4.5V -20°C to +70°C, unless otherwise noted PARAMETER SYMBOL Input Logic-High: SCL, SDA Input Logic-Low: SCL, SDA Output Logic-Low: SDA Pulldown Current: SCL, SDA ...
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Stand-Alone OCV-Based Fuel Gauge ELECTRICAL CHARACTERISTICS: 2-WIRE INTERFACE (continued) (2.5V ≤ V ≤ 4.5V -20°C to +70°C Note 6: The maximum t has only to be met if the device does not stretch the low period ...
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Stand-Alone OCV-Based Fuel Gauge TOP VIEW PIN NAME 1 AIN1 Auxiliary Voltage Input Number 1 2 AIN0 Auxiliary Voltage Input Number 0 Serial Clock Input. Input only 2-wire clock line. Connect this pin to the clock signal of the 2-wire ...
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Stand-Alone OCV-Based Fuel Gauge Detailed Description The DS2786B provides current-flow, voltage, and temperature-measurement data to support battery- capacity monitoring in cost-sensitive applications. Current is measured bidirectionally over a dynamic range of ±51.2mV with a resolution of 25µV. Assuming a 15mΩ ...
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Stand-Alone OCV-Based Fuel Gauge BATTERY PROTECTION IC (Li+/POLYMER) 1nF 1nF Figure 3. Application Example The DS2786B provides accurate relative capacity mea- surements during periods of host system inactivity by looking at cell open-circuit voltage. Cell capacity is cal- culated using ...
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Stand-Alone OCV-Based Fuel Gauge Parameter Measurement The DS2786B uses a sigma-delta A/D converter to make measurements. The measurement sequence shown in Figure 4 repeats continuously while the DS2786B is in Active Mode. The V t before the AIN0 and AIN1 ...
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Stand-Alone OCV-Based Fuel Gauge Voltage Measurement Battery voltage is measured at the over 4.999V range and with a resolution of SS 1.22mV. The result is updated every 880ms and placed in the Voltage Register ...
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Stand-Alone OCV-Based Fuel Gauge Temperature Measurement The DS2786B uses an integrated temperature sensor to measure battery temperature with a resolution of 0.125°C. Temperature measurements are updated every 1760ms and placed in the Temperature Register in two’s-complement form. The format of ...
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Stand-Alone OCV-Based Fuel Gauge Current Offset Bias The Current Offset Bias Register (COBR) allows a pro- grammable offset value to be added to raw current measurements. The result of the raw current measure- ment plus the COBR value is displayed ...
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Stand-Alone OCV-Based Fuel Gauge Prior to the first learn operation, the relative capacity value is calculated by adding the IACR multiplied by the initial capacity scaling factor (7Ah) to the last OCV rela- tive capacity (16h). After the first learn ...
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Stand-Alone OCV-Based Fuel Gauge OCV Cell Model The OCV cell model is a 9-point piece-wise linear approximation of open-circuit cell voltage vs. the remaining capacity of the cell. Whenever an OCV update occurs, the Relative Capacity Register is adjust- ed ...
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Stand-Alone OCV-Based Fuel Gauge MSB—EVEN ADDRESSES 68h–78h MSB “X”: RESERVED Figure 17. Voltage Breakpoint Register Format Initial Capacity Estimation The DS2786B calculates relative capacity immediately upon power-up. During initialization, the ...
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Stand-Alone OCV-Based Fuel Gauge ADDRESS 7Eh MSB Figure 20. Learn Delta Percent Threshold The learn delta percent threshold allows the application to select how large a cell capacity change is ...
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Stand-Alone OCV-Based Fuel Gauge Table 3. Memory Map ADDRESS DESCRIPTION 00h Reserved 01h Status/Config Register 02h Relative Capacity 03h to 07h Reserved 08h Auxiliary Input 0 MSB 09h Auxiliary Input 0 LSB Auxiliary Input 1/ 0Ah Temperature MSB Auxiliary Input ...
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Stand-Alone OCV-Based Fuel Gauge Status/Config Register The Status/Config Register is read/write with individual bits designated as read only. Bit values indicate status as well as program or select device functionality. Bits 3 though 6 are EEPROM backed at memory location ...
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Stand-Alone OCV-Based Fuel Gauge • COPY—The Copy bit is set to start a copy command of the scratchpad to EEPROM. A programming volt- age must be present on the V PROG copy to be successful. The Copy bit must be ...
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Stand-Alone OCV-Based Fuel Gauge A bus master initiates communication with a slave device by issuing a START condition followed by a slave address (SAddr) and the read/write (R/W) bit. When the bus is idle, the DS2786B continuously moni- tors for ...
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Stand-Alone OCV-Based Fuel Gauge Basic Transaction Formats Write: S SAddr W A MAddr A Data0 write transaction transfers 1 or more data bytes to the DS2786B. The data transfer begins at the memory address supplied in the ...
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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. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 21 © 2010 Maxim Integrated Products ...