JAJSNC1F September   2006  – January 2022 BQ2022A

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 Pin Configuration and Functions
  6. 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 Electrical Characteristics: DC
    6. 6.6 Switching Characteristics: AC
    7. 6.7 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 1024-Bit EPROM
      2. 7.3.2 EPROM Status Memory
      3. 7.3.3 Error Checking
      4. 7.3.4 Customizing the BQ2022A
      5. 7.3.5 Bus Termination
    4. 7.4 Device Functional Modes
    5. 7.5 Programming
      1. 7.5.1  Serial Communication
      2. 7.5.2  Initialization
      3. 7.5.3  ROM Commands
        1. 7.5.3.1 READ ROM Command
        2. 7.5.3.2 SKIP ROM Command
      4. 7.5.4  Memory/Status Function Commands
      5. 7.5.5  READ MEMORY Commands
        1. 7.5.5.1 READ MEMORY/Page CRC
        2. 7.5.5.2 READ MEMORY/Field CRC
      6. 7.5.6  WRITE MEMORY Command
      7. 7.5.7  READ STATUS Command
      8. 7.5.8  WRITE STATUS Command
      9. 7.5.9  PROGRAM PROFILE Byte
      10. 7.5.10 SDQ Signaling
      11. 7.5.11 RESET and PRESENCE PULSE
      12. 7.5.12 WRITE Bit
      13. 7.5.13 READ Bit
      14. 7.5.14 PROGRAM PULSE
      15. 7.5.15 IDLE
      16. 7.5.16 CRC Generation
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Programming Circuit Example
        2. 8.2.2.2 SDQ Master Best Practices
      3. 8.2.3 Application Curve
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Third-Party Products Disclaimer
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
      2. 11.2.2 Receiving Notification of Documentation Updates
    3. 11.3 Trademarks
    4. 11.4 サポート・リソース
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

7.5.3.1 READ ROM Command

The READ ROM command sequence is the fastest sequence that allows the host to read the 8-bit family code and 48-bit identification number. The READ ROM sequence starts with the host generating the RESET pulse of at least 480 μs. The BQ2022A responds with a PRESENCE pulse. Next, the host continues by issuing the READ ROM command, 33h, and then reads the ROM and CRC byte using the READ signaling (see the READ and WRITE signals section) during the data frame.

GUID-3A36D041-A9BF-4861-AA87-C2FC30C23EFE-low.gifFigure 7-1 READ ROM Sequence