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

Package Options

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

Design Requirements

Table 8-1 shows the default settings for the main parameters. Use the bqStudio tool to update the settings to meet the specific application or battery pack configuration requirements.

The device should be calibrated before any gauging test. Follow the bqStudio Calibration page to calibrate the device, and use the bqStudio Chemistry page to update the match chemistry profile to the device.

Table 8-1 Design Parameters
DESIGN PARAMETEREXAMPLE
Cell Configuration3S1P (3-series with 1-parallel)(1)
Design Capacity4400mAh
Device Chemistry1210 (LiCoO2/graphitized carbon)
Cell Overvoltage at Standard Temperature4300mV
Cell Undervoltage2500mV
Shutdown Voltage2300mV
Overcurrent in CHARGE Mode6000mA
Overcurrent in DISCHARGE Mode–6000mA
Short Circuit in DISCHARGE Mode0.1V/RSense across SRP, SRN
Safety Overvoltage4500mV
Cell BalancingDisabled
Internal and External Temperature SensorExternal Temperature Sensor is used.
Undertemperature Charging0°C
Undertemperature Discharging0°C
BROADCAST ModeDisabled
When using the device the first time, if a 2S battery pack is used, then a charger or power supply should be connected to the PACK+ terminal to prevent device shutdown. Then update the cell configuration before removing the charger connection.