SLUSFB5 June   2024 BQ41Z50

ADVANCE INFORMATION  

  1.   1
  2. Features
  3. Applications
  4. Description
  5. Description (continued)
  6. Pin Configuration and Functions
    1. 5.1 Pin Equivalent Diagrams
  7. Specifications
    1. 6.1  Absolute Maximum Ratings
    2. 6.2  ESD Ratings
    3. 6.3  Recommended Operating Conditions
    4. 6.4  Thermal Information
    5. 6.5  Supply Current
    6. 6.6  Power Supply Control
    7. 6.7  Current Wake Detector
    8. 6.8  VC0, VC1, VC2, VC3, VC4, PACK
    9. 6.9  SMBD, SMBC
    10. 6.10 PRES/SHUTDN, DISP
    11. 6.11 ALERT
    12. 6.12 Coulomb Counter Digital Filter (CC1)
    13. 6.13 ADC Digital Filter
    14. 6.14 CHG, DSG High-side NFET Drivers
    15. 6.15 Precharge (PCHG) FET Drive
    16. 6.16 FUSE Drive
    17. 6.17 Internal Temperature Sensor
    18. 6.18 TS1, TS2, TS3, TS4
    19. 6.19 Flash Memory
    20. 6.20 GPIO1, GPIO2, GPIO3, GPIO4, GPIO5, GPIO6, GPIO7
    21. 6.21 Elliptical Curve Cryptography (ECC)
    22. 6.22 SMBus Interface Timing
    23. 6.23 Typical Characteristics
  8. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Primary (1st Level) Safety Features
      2. 7.3.2 Secondary (2nd Level) Safety Features
      3. 7.3.3 Charge Control Features
      4. 7.3.4 Gas Gauging
      5. 7.3.5 Lifetime Data Logging Features
      6. 7.3.6 Authentication
      7. 7.3.7 Configuration
        1. 7.3.7.1 Oscillator Function
        2. 7.3.7.2 Real Time Clock
        3. 7.3.7.3 System Present Operation
        4. 7.3.7.4 Emergency Shutdown
        5. 7.3.7.5 2-Series, 3-Series, or 4-Series Cell Configuration
        6. 7.3.7.6 Cell Balancing
        7. 7.3.7.7 LED Display
      8. 7.3.8 Battery Parameter Measurements
        1. 7.3.8.1 Charge and Discharge Counting
        2. 7.3.8.2 Voltage
        3. 7.3.8.3 Current
        4. 7.3.8.4 Temperature
        5. 7.3.8.5 Communications
          1. 7.3.8.5.1 SMBus On and Off State
    4. 7.4 Device Functional Modes
  9. Applications and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 High-Current Path
          1. 8.2.2.1.1 Protection FETs
          2. 8.2.2.1.2 Chemical Fuse
          3. 8.2.2.1.3 Lithium-Ion Cell Connections
          4. 8.2.2.1.4 Sense Resistor
          5. 8.2.2.1.5 ESD Mitigation
        2. 8.2.2.2 Gas Gauge Circuit
          1. 8.2.2.2.1 Coulomb-Counting Interface
          2. 8.2.2.2.2 Low-dropout Regulators (LDOs)
            1. 8.2.2.2.2.1 REG18
            2. 8.2.2.2.2.2 REG135
          3. 8.2.2.2.3 System Present
          4. 8.2.2.2.4 SMBus Communication
          5. 8.2.2.2.5 FUSE Circuitry
        3. 8.2.2.3 Secondary-Current Protection
          1. 8.2.2.3.1 Cell and Battery Inputs
          2. 8.2.2.3.2 External Cell Balancing
          3. 8.2.2.3.3 PACK and FET Control
          4. 8.2.2.3.4 Temperature Measurement
          5. 8.2.2.3.5 LEDs
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
        1. 8.4.1.1 Protector FET Bypass and Pack Terminal Bypass Capacitors
        2. 8.4.1.2 ESD Spark Gap
      2. 8.4.2 Layout Example
  10. Device and Documentation Support
    1. 9.1 Third-Party Products Disclaimer
    2. 9.2 Documentation Support
      1. 9.2.1 Related Documentation
    3. 9.3 Receiving Notification of Documentation Updates
    4. 9.4 Support Resources
    5. 9.5 Trademarks
    6. 9.6 Electrostatic Discharge Caution
    7. 9.7 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

Charge Control Features

The BQ41Z50 charge control features include:

  • Supports JEITA temperature ranges. Reports charging voltage and charging current according to the active temperature range
  • Handles more complex charging profiles. Allows for splitting the standard temperature range into two sub-ranges and allows for varying the charging current according to the cell voltage
  • Reports the appropriate charging current needed for constant current charging and the appropriate charging voltage needed for constant voltage charging to a smart charger using SMBus broadcasts
  • Reduces the charge difference of the battery cells in fully charged state of the battery pack gradually using a voltage-based cell balancing algorithm during charging. A voltage threshold can be set up for cell balancing to be active. This prevents fully charged cells from overcharging and causing excessive degradation and also increases the usable pack energy by preventing premature charge termination.
  • Supports pre-charging
  • Supports charge inhibit and charge suspend if battery pack temperature is out of temperature range
  • Reports charging fault and also indicates charge status via charge and discharge alarms