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SBS 1.1 compliant gas gauge with integrated Oscillator for use with The bq29311

Replaced by: BQ4050RSMR



Qty Price (USD)
1-99 17.037
100-249 14.881
250-999 11.474
1,000+ 10.263

Quality information

RoHS Yes
Lead finish / Ball material NIPDAU
MSL rating / Peak reflow Level-2-260C-1 YEAR
Quality, reliability
& packaging information info-circle

Information included:

  • RoHS
  • Device marking
  • Lead finish/Ball material
  • MSL rating/Peak reflow
  • MTBF/FIT estimates
  • Material content
  • Qualification summary
  • Ongoing reliability monitoring
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Export classification

*For reference only

  • US ECCN: EAR99

Packaging information

Package | Pins TSSOP (DBT) | 38
Package qty | Carrier: 50 | TUBE
Operating temperature range (°C) -20 to 85
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Features for the BQ2085

  • Provides Accurate Measurement of Available Charge in Li-Ion and Li-Polymer Batteries
  • Supports the Smart Battery Specification (SBS) V1.1
  • Integrated Time Base Removes Need for External Crystal
  • Works With the TI bq29311 Analog Front End (AFE) Protection IC to Provide Complete Pack Electronics for 10.8-V or 14.4-V Battery Packs With Few External Components
  • Based on a Powerful Low-Power RISC CPU Core With High-Performance Peripherals
  • Integrated FLASH Memory Eliminates the Need for External Configuration EEPROM
  • Measures Charge Flow Using a High Resolution 16-Bit Integrating Converter
    • Better Than 3-nVh of Resolution
    • Self-Calibrating
    • Offset Error Less Than 1-uV
  • Uses 16-Bit Delta Sigma Converter for Accurate Voltage and Temperature Measurements
  • Programmable Cell Modeling for Maximum Battery Fuel Gauge Accuracy
  • Drives 3-, 4-, or 5-Segment LED Display for Remaining Capacity Indication
  • 38-Pin TSSOP (DBT)
    • Notebook PCs
    • Medical and Test Equipment
    • Portable Instrumentation

Description for the BQ2085

The bq2085 SBS-compliant gas gauge IC for battery pack or in-system installation maintains an accurate record of available charge in Li-ion or Li-polymer batteries. The bq2085 monitors capacity and other critical parameters of the battery pack and reports the information to the system host controller over a serial communication bus. It is designed to work with the bq29311 analog front-end (AFE) protection IC to maximize functionality and safety and minimize component count and cost in smart battery circuits. Using information from the bq2085, the host controller can manage remaining battery power to extend the system run time as much as possible.

The bq2085 uses an integrating converter with continuous sampling for the measurement of battery charge and discharge currents. Optimized for coulomb counting in portable applications, the self-calibrating integrating converter has a resolution better than 3-nVh and an offset measurement error of less than 1-uV (typical). For voltage and temperature reporting, the bq2085 uses a 16-bit A-to-D converter. In conjunction with the bq29311, the onboard ADC also monitors individual cell voltages in a battery pack and allows the bq2085 to generate the control signals necessary to implement the cell balancing and the required safety protection for Li-ion and Li-polymer battery chemistries.

The bq2085 supports the Smart Battery Data (SBData) commands and charge-control functions. It communicates data using the System Management Bus (SMBus) 2-wire protocol. The data available include the battery’s remaining capacity, temperature, voltage, current, and remaining run-time predictions. The bq2085 provides LED drivers and a push-button input to depict remaining battery capacity from full to empty in 20%, 25%, or 33% increments with a 3-, 4-, or 5-segment display.

The bq2085 contains 512 bytes of internal data flash memory, which store configuration information. The information includes nominal capacity and voltage, self-discharge rate, rate compensation factors, and other programmable cell-modeling factors used to accurately adjust remaining capacity for use-conditions based on time, rate, and temperature. The bq2085 also automatically calibrates or learns the true battery capacity in the course of a discharge cycle from programmable near full to near empty levels.

The bq29311 AFE protection IC provides power to the bq2085 from a 3 or 4 series Li-ion cell stack, eliminating the need for an external regulator circuit.



Qty Price (USD)
1-99 17.037
100-249 14.881
250-999 11.474
1,000+ 10.263

Carrier options

You can choose different carrier options based on the quantity of parts, including full reel, custom reel, cut tape, tube or tray.

custom reel is a continuous length of cut tape from one reel to maintain lot- and date-code traceability, built to the exact quantity requested. Following industry standards, a brass shim connects an 18-inch leader and trailer on both sides of the cut tape for direct feeding into automated assembly machines. TI includes a reeling fee for custom reel orders.

Cut tape is a length of tape cut from a reel. TI may fulfill orders using multiple strips of cut tapes or boxes to satisfy the quantity requested.

TI often ships  tube or tray  devices inside a box or in the tube or tray, depending on inventory availability. We pack all tapes, tubes or sample boxes according to internal electrostatic discharge and moisture-sensitivity-level protection requirements.

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Lot and date code selection may be available

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