JAJSCB2K April   2020  – July 2020 BQ77904 , BQ77905

PRODUCTION DATA  

  1. 1 特長
  2. 2 アプリケーション
  3. 3 概要
  4. 4 Revision History
  5. 5 Device Comparison
  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 Electrical Characteristics
    6. 7.6 Timing Requirements
    7. 7.7 Typical Characteristics
  8. 8 Detailed Description
    1. 8.1 Overview
      1. 8.1.1 Device Functionality Summary
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1  Protection Summary
      2. 8.3.2  Fault Operation
        1. 8.3.2.1  Operation in OV
        2. 8.3.2.2  Operation in UV
        3. 8.3.2.3  Operation in OW
        4. 8.3.2.4  Operation in OCD1
        5. 8.3.2.5  Operation in OCD2
        6. 8.3.2.6  Operation in SCD
        7. 8.3.2.7  Overcurrent Recovery Timer
        8. 8.3.2.8  Load Removal Detection
        9. 8.3.2.9  Load Removal Detection in UV
        10. 8.3.2.10 Operation in OTC
        11. 8.3.2.11 Operation in OTD
        12. 8.3.2.12 Operation in UTC
        13. 8.3.2.13 Operation in UTD
      3. 8.3.3  Protection Response and Recovery Summary
      4. 8.3.4  Configuration CRC Check and Comparator Built-In-Self-Test
      5. 8.3.5  Fault Detection Method
        1. 8.3.5.1 Filtered Fault Detection
      6. 8.3.6  State Comparator
      7. 8.3.7  DSG FET Driver Operation
      8. 8.3.8  CHG FET Driver Operation
      9. 8.3.9  External Override of CHG and DSG Drivers
      10. 8.3.10 Configuring 3-S, 4-S, or 5-S Mode
      11. 8.3.11 Stacking Implementations
      12. 8.3.12 Zero-Volt Battery Charging Inhibition
    4. 8.4 Device Functional Modes
      1. 8.4.1 Power Modes
        1. 8.4.1.1 Power-On Reset (POR)
        2. 8.4.1.2 FAULT Mode
        3. 8.4.1.3 SHUTDOWN Mode
        4. 8.4.1.4 Customer Fast Production Test Modes
  9. 9 Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 Recommended System Implementation
        1. 9.1.1.1 CHG and DSG FET Rise and Fall Time
        2. 9.1.1.2 Protecting CHG and LD
        3. 9.1.1.3 Protecting CHG FET
        4. 9.1.1.4 Using Load Detect for UV Fault Recovery
        5. 9.1.1.5 Temperature Protection
        6. 9.1.1.6 Adding Filter to Sense Resistor
        7. 9.1.1.7 Using a State Comparator in an Application
          1. 9.1.1.7.1 Examples
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Design Example
      3. 9.2.3 Application Curves
    3. 9.3 System Examples
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Documentation Support
      1. 12.1.1 Related Links
    2. 12.2 Receiving Notification of Documentation Updates
    3. 12.3 サポート・リソース
    4. 12.4 Trademarks
    5. 12.5 Electrostatic Discharge Caution
    6. 12.6 用語集
  13. 13Mechanical, Packaging, and Orderable Information

パッケージ・オプション

メカニカル・データ（パッケージ｜ピン）
サーマルパッド・メカニカル・データ
発注情報

8.1 Overview

The BQ77904 and BQ77905 families are full-feature stackable primary protectors for Li-ion/Li-Polymer batteries. The devices implement a suite of protections, including:

  • Cell voltage: overvoltage, undervoltage
  • Current: Overcurrent discharge 1 and 2, short circuit discharge
  • Temperature: overtemperature and undertemperature in charge and discharge
  • PCB: cell open-wire connection
  • FET body diode protection
Protection thresholds and delays are factory-programmed and available in a variety of configurations.

The BQ77904 supports 3-series-to–4-series cell configuration and BQ77905 supports 3-series-to–5-series cell configuration. Up to four devices can be stacked to support ≥6-series cell configurations, providing protections up to 20-series cell configurations.

The device has built-in CHG and DSG drivers for low-side N-channel FET protection, which automatically open up the CHG and/or DSG FETs after protection delay time when a fault is detected. A set of CHG/DSG overrides is provided to allow disabling of CHG and/or DSG driver externally. Although the host system can use this function to disable the FETs' control, the main use of these pins is to channel down the FET control signal from the upper device to the lower device in a cascading configuration in ≥6-series battery packs.