SLUSFQ1C December   2024  – October 2026 BQ41Z90

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions:
  6. 5 Pin Equivalent Diagrams
  7. 6 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 Selector
    7. 6.7  Current Wake Detector
    8. 6.8  General Purpose Input-Outputs
    9. 6.9  Aux REGOUT LDO
    10. 6.10 LD Pin
    11. 6.11 Shelf Timer
    12. 6.12 Cell Balancing
    13. 6.13 Comparator-Based Detections (SCOMP)
    14. 6.14 SCOMP Timing Requirements
    15. 6.15 SCD Comparator
    16. 6.16 High-side NFET Drivers (CHG and DSG and PCHG and PDSG)
    17. 6.17 FUSE Pin
    18. 6.18 Flash Memory
    19. 6.19 Interface I/O
    20. 6.20 I2C Interface Timing
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Device Functional Modes
        1. 7.3.1.1 Analog Front End (AFE)
        2. 7.3.1.2 Power Management
          1. 7.3.1.2.1 Power Mode Configuration
          2. 7.3.1.2.2 Power Supply Control
            1. 7.3.1.2.2.1 HIBERNATE Mode
            2. 7.3.1.2.2.2 SHUTDOWN Mode
            3. 7.3.1.2.2.3 SHELF Mode
            4. 7.3.1.2.2.4 Wake Functionality
          3. 7.3.1.2.3 Power Management Unit
            1. 7.3.1.2.3.1 PMU Overview
          4. 7.3.1.2.4 Thermal Shutdown
          5. 7.3.1.2.5 Low Drop Out Regulators (LDOs)
            1. 7.3.1.2.5.1 REG18
            2. 7.3.1.2.5.2 REG135
            3. 7.3.1.2.5.3 REGIO
            4. 7.3.1.2.5.4 REGOUT
        3. 7.3.1.3 Reset Management
          1. 7.3.1.3.1 AFE Watchdog
        4. 7.3.1.4 Diagnostics Features
        5. 7.3.1.5 Internal Oscillators
          1. 7.3.1.5.1 Low Frequency Oscillator (LFO)
          2. 7.3.1.5.2 High Frequency Oscillator (HFO)
          3. 7.3.1.5.3 Low Power Oscillator (LPO)
      2. 7.3.2 Temperature Measurement
        1. 7.3.2.1 External Temperature Measurement Support
        2. 7.3.2.2 Internal Temperature Sensor
      3. 7.3.3 Random Cell Connection Support
        1. 7.3.3.1 Usage of VC Pins for Cells Versus Interconnect
        2. 7.3.3.2 Unused Pins
      4. 7.3.4 Cell Balancing Support
        1. 7.3.4.1 Open Wire Detection
      5. 7.3.5 Protection and Charge Control Outputs
        1. 7.3.5.1 High-Side NFET Drivers
        2. 7.3.5.2 PRECHARGE and PREDISCHARGE Modes
        3. 7.3.5.3 FET Configuration
        4. 7.3.5.4 CFETOFF, DFETOFF Pin Functionality
        5. 7.3.5.5 DDSG and DCHG Pin Operation
        6. 7.3.5.6 Hardware Fault Detection (SCOMP and SCD)
        7. 7.3.5.7 FET UVLO Protection
        8. 7.3.5.8 Fuse Drive
      6. 7.3.6 Load Detect Functionality
      7. 7.3.7 MCU Peripherals
        1. 7.3.7.1 General Purpose and Special Function I/O
          1. 7.3.7.1.1 Low Voltage RAx I/O
          2. 7.3.7.1.2 Low Voltage RCx I/O
          3. 7.3.7.1.3 Constant Current Sink I/O
        2. 7.3.7.2 Communication Interfaces
          1. 7.3.7.2.1 I2C Interface
          2. 7.3.7.2.2 SMBus Interface
        3. 7.3.7.3 Authentication Support
          1. 7.3.7.3.1 ECC Authentication
          2. 7.3.7.3.2 SHA-1 Support
          3. 7.3.7.3.3 SHA-2 Support
  9. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 Design Requirements
    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. 9 Device and Documentation Support
    1. 9.1 Third-Party Products Disclaimer
    2. 9.2 Documentation Support
    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

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • PVP|64
Thermal pad, mechanical data (Package|Pins)
Orderable Information

7.3.4 Cell Balancing Support

The integrated cell balancing FETs included in BQ41Z90 device allow the AFE to bypass cell current around a given cell or numerous cells to effectively balance the entire battery stack. External series resistors placed between the cell connections and the VCx input pins set the balancing current magnitude, which must be restricted to a maximum of ICB.

The cell balancing circuitry can be enabled or disabled through configuring the CB_CTRL[CB_CELBAL] control register. Series input resistors between 20Ω and 100Ω and are recommended for effective cell balancing.

A normal VCELL measurement through the ADC using the state machine automatically disables the selected cell balancing FET and adjacent cell balancing FETs for the ADC Config Time and the ADC measurement time. This setting provides the most accurate VCELL measurement. Once the ADC measurement is finished, then the cell balancing FETs are immediately returned to the preconfigured condition.