SLUSC53B May   2015  – May 2018

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Simplified Schematic
  4. 4 Revision History
  5. 5 Device Comparison Table
  6. 6 Pin Configuration and Functions
    1.     Pin Functions
  7. 7 Specifications
    1. 7.1  Absolute Maximum Ratings
    2. 7.2  ESD Ratings
    3. 7.3  Recommended Operating Conditions
    4. 7.4  Thermal Information
    5. 7.5  Supply Current
    6. 7.6  Digital Input and Output DC Characteristics
    7. 7.7  Power-On Reset
    8. 7.8  2.5-V LDO Regulator
    9. 7.9  Internal Clock Oscillators
    10. 7.10 Integrating ADC (Coulomb Counter) Characteristics
    11. 7.11 ADC (Temperature and Cell Voltage) Characteristics
    12. 7.12 Data Flash Memory Characteristics
    13. 7.13 HDQ Communication Timing Characteristics
    14. 7.14 I2C-Compatible Interface Timing Characteristics
    15. 7.15 Typical Characteristics
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Fuel Gauging
      2. 8.3.2 Impedance Track Variables
      3. 8.3.3 Power Control
        1. 8.3.3.1 Reset Functions
        2. 8.3.3.2 Wake-Up Comparator
        3. 8.3.3.3 Flash Updates
      4. 8.3.4 Autocalibration
      5. 8.3.5 Communications
        1. 8.3.5.1 Authentication
        2. 8.3.5.2 Key Programming (Data Flash Key)
        3. 8.3.5.3 Key Programming (Secure Memory Key)
        4. 8.3.5.4 Executing an Authentication Query
        5. 8.3.5.5 HDQ Single-Pin Serial Interface
        6. 8.3.5.6 HDQ Host Interruption Feature
          1. 8.3.5.6.1 Low Battery Capacity
          2. 8.3.5.6.2 Temperature
        7. 8.3.5.7 I2C Interface
          1. 8.3.5.7.1 I2C Time Out
          2. 8.3.5.7.2 I2C Command Waiting Time
          3. 8.3.5.7.3 I2C Clock Stretching
    4. 8.4 Device Functional Modes
      1. 8.4.1 Power Modes
        1. 8.4.1.1 NORMAL Mode
        2. 8.4.1.2 SLEEP Mode
        3. 8.4.1.3 FULLSLEEP Mode
        4. 8.4.1.4 HIBERNATE Mode
      2. 8.4.2 System Control Function
        1. 8.4.2.1 SHUTDOWN Mode
        2. 8.4.2.2 INTERRUPT Mode
      3. 8.4.3 Security Modes
        1. 8.4.3.1 Sealing and Unsealing Data Flash
    5. 8.5 Programming
      1. 8.5.1 Standard Data Commands
        1. 8.5.1.1 Control(): 0x00 and 0x01
    6. 8.6 Register Maps
      1. 8.6.1 Pack Configuration Register
      2. 8.6.2 Pack Configuration B Register
      3. 8.6.3 Pack Configuration C Register
  9. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Applications
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 BAT Voltage Sense Input
        2. 9.2.2.2 SRP and SRN Current Sense Inputs
        3. 9.2.2.3 Sense Resistor Selection
        4. 9.2.2.4 TS Temperature Sense Input
        5. 9.2.2.5 Thermistor Selection
        6. 9.2.2.6 REGIN Power Supply Input Filtering
        7. 9.2.2.7 VCC LDO Output Filtering
    3. 9.3 Application Curves
  10. 10Power Supply Recommendations
    1. 10.1 Power Supply Decoupling
  11. 11Layout
    1. 11.1 Layout Guidelines
      1. 11.1.1 Sense Resistor Connections
      2. 11.1.2 Thermistor Connections
      3. 11.1.3 High-Current and Low-Current Path Separation
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Documentation Support
      1. 12.1.1 Related Documentation
    2. 12.2 Community Resources
    3. 12.3 Trademarks
    4. 12.4 Electrostatic Discharge Caution
    5. 12.5 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

9.2.1 Design Requirements

Several key parameters must be updated to align with a given application's battery characteristics. For highest accuracy gauging, it is important to follow-up this initial configuration with a learning cycle to optimize resistance and maximum chemical capacity (Qmax) values prior to sealing and shipping systems to the field. Successful and accurate configuration of the fuel gauge for a target application can be used as the basis for creating a "golden" file that can be written to all gauges, assuming identical pack design and Li-Ion cell origin (chemistry, lot, and so on). Calibration data is included as part of this golden file to cut down on system production time. If using this method, it is recommended to average the voltage and current measurement calibration data from a large sample size and use these in the golden file. Table 12 shows the items that should be configured to achieve reliable protection and accurate gauging with minimal initial configuration.

Table 12. Key Data Flash Parameters for Configuration

NAME DEFAULT UNIT RECOMMENDED SETTING
Design Capacity 1000 mAh Set based on the nominal pack capacity as interpreted from the cell manufacturer's data sheet. If multiple parallel cells are used, should be set to N × Cell Capacity.
Design Energy Scale 1 — Set to 10 to convert all power values to cWh or to 1 for mWh. Design Energy is divided by this value.
Reserve Capacity-mAh 0 mAh Set to desired runtime remaining (in seconds/3600) × typical applied load between reporting 0% SOC and reaching Terminate Voltage, if needed.
Cycle Count Threshold 900 mAh Set to 90% of configured Design Capacity.
Chem ID 0100 hex Should be configured using TI-supplied Battery Management Studio (bqStudio) software. Default open-circuit voltage and resistance tables are also updated in conjunction with this step.
Do not attempt to manually update reported Device Chemistry as this does not change all chemistry information. Always update chemistry using the bqStudio software tool.
Load Mode 1 — Set to applicable load model, 0 for constant current or 1 for constant power.
Load Select 1 — Set to load profile which most closely matches typical system load.
Qmax Cell 0 1000 mAh Set to initial configured value for Design Capacity. The gauge will update this parameter automatically after the optimization cycle and for every regular Qmax update thereafter.
Cell0 V at Chg Term 4200 mV Set to nominal cell voltage for a fully charged cell. The gauge will update this parameter automatically each time full charge termination is detected.
Terminate Voltage 3200 mV Set to empty point reference of battery based on system needs. Typical is between 3000 and 3200 mV.
Ra Max Delta 44 mΩ Set to 15% of Cell0 R_a 4 resistance after an optimization cycle is completed.
Charging Voltage 4200 mV Set based on nominal charge voltage for the battery in normal conditions (25°C, and so on). Used as the reference point for offsetting by Taper Voltage for full charge termination detection.
Taper Current 100 mA Set to the nominal taper current of the charger + taper current tolerance to ensure that the gauge will reliably detect charge termination.
Taper Voltage 100 mV Sets the voltage window for qualifying full charge termination. Can be set tighter to avoid or wider to ensure possibility of reporting 100% SOC in outer JEITA temperature ranges that use derated charging voltage.
Dsg Current Threshold 60 mA Sets threshold for gauge detecting battery discharge. Should be set lower than minimal system load expected in the application and higher than Quit Current.
Chg Current Threshold 75 mA Sets the threshold for detecting battery charge. Can be set higher or lower depending on typical trickle charge current used. Also should be set higher than Quit Current.
Quit Current 40 mA Sets threshold for gauge detecting battery relaxation. Can be set higher or lower depending on typical standby current and exhibited in the end system.
Avg I Last Run –299 mA Current profile used in capacity simulations at onset of discharge or at all times if Load Select = 0. Should be set to nominal system load. Is automatically updated by the gauge every cycle.
Avg P Last Run –1131 mW Power profile used in capacity simulations at onset of discharge or at all times if Load Select = 0. Should be set to nominal system power. Is automatically updated by the gauge every cycle.
Sleep Current 15 mA Sets the threshold at which the fuel gauge enters SLEEP mode. Take care in setting above typical standby currents else entry to SLEEP may be unintentionally blocked.
Charge T0 0 °C Sets the boundary between charging inhibit and charging with T0 parameters.
Charge T1 10 °C Sets the boundary between charging with T0 and T1 parameters.
Charge T2 45 °C Sets the boundary between charging with T1 and T2 parameters.
Charge T3 50 °C Sets the boundary between charging with T2 and T3 parameters.
Charge T4 60 °C Sets the boundary between charging with T3 and T4 parameters.
Charge Current T0 50 % Des Cap Sets the charge current parameter for T0.
Charge Current T1 50 % Des Cap Sets the charge current parameter for T1.
Charge Current T2 50 % Des Cap Sets the charge current parameter for T2.
Charge Current T3 50 % Des Cap Sets the charge current parameter for T3.
Charge Current T4 0 % Des Cap Sets the charge current parameter for T4.
Charge Voltage T0 210 20 mV Sets the charge voltage parameter for T0.
Charge Voltage T1 210 20 mV Sets the charge voltage parameter for T1.
Charge Voltage T2 207 20 mV Sets the charge voltage parameter for T2.
Charge Voltage T3 205 20 mV Sets the charge voltage parameter for T3.
Charge Voltage T4 0 20 mV Sets the charge voltage parameter for T4.
Chg Temp Hys 5 °C Adds temperature hysteresis for boundary crossings to avoid oscillation if temperature is changing by a degree or so on a given boundary.
Chg Disabled Regulation V 4200 mV Sets the voltage threshold for voltage regulation to system when charge is disabled. It is recommended to program to same value as Charging Voltage and maximum charge voltage that is obtained from Charge Voltage T0–4 parameters.
CC Gain 10 mΩ Calibrate this parameter using TI-supplied bqStudio software and calibration procedure in the TRM. Determines conversion of coulomb counter measured sense resistor voltage to current.
CC Delta 10 mΩ Calibrate this parameter using TI-supplied bqStudio software and calibration procedure in the TRM. Determines conversion of coulomb counter measured sense resistor voltage to passed charge.
CC Offset –1418 Counts Calibrate this parameter using TI-supplied bqStudio software and calibration procedure in the TRM. Determines native offset of coulomb counter hardware that should be removed from conversions.
Board Offset 0 Counts Calibrate this parameter using TI-supplied bqStudio software and calibration procedure in the TRM. Determines native offset of the printed circuit board parasitics that should be removed from conversions.
Pack V Offset 0 mV Calibrate this parameter using TI-supplied bqStudio software and calibration procedure in the TRM. Determines voltage offset between cell tab and ADC input node to incorporate back into or remove from measurement, depending on polarity.