JAJSJO6C December   2021  – August 2024 LM63440-Q1 , LM63460-Q1

PRODUCTION DATA  

  1.   1
  2. 1 特長
  3. 2 アプリケーション
  4. 3 概要
  5. 4 Device Comparison Table
  6. 5 Pin Configuration and Functions
    1. 5.1 Wettable Flanks
    2. 5.2 Pinout Design for Clearance and FMEA
  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 Electrical Characteristics
    6. 6.6 Timing Characteristics
    7. 6.7 Systems Characteristics
    8. 6.8 Typical Characteristics
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  Input Voltage Range (VIN1, VIN2)
      2. 7.3.2  Output Voltage Setpoint (FB)
      3. 7.3.3  Precision Enable and Input Voltage UVLO (EN/SYNC)
      4. 7.3.4  Frequency Synchronization (EN/SYNC)
      5. 7.3.5  Clock Locking
      6. 7.3.6  Adjustable Switching Frequency (RT)
      7. 7.3.7  Power-Good Monitor (PGOOD)
      8. 7.3.8  Bias Supply Regulator (VCC, BIAS)
      9. 7.3.9  Bootstrap Voltage and UVLO (CBOOT)
      10. 7.3.10 Spread Spectrum
      11. 7.3.11 Soft Start and Recovery From Dropout
      12. 7.3.12 Overcurrent and Short-Circuit Protection
      13. 7.3.13 Thermal Shutdown
      14. 7.3.14 Input Supply Current
    4. 7.4 Device Functional Modes
      1. 7.4.1 Shutdown Mode
      2. 7.4.2 Standby Mode
      3. 7.4.3 Active Mode
        1. 7.4.3.1 CCM Mode
        2. 7.4.3.2 AUTO Mode – Light-Load Operation
          1. 7.4.3.2.1 Diode Emulation
          2. 7.4.3.2.2 Frequency Foldback
        3. 7.4.3.3 FPWM Mode – Light-Load Operation
        4. 7.4.3.4 Minimum On-Time (High Input Voltage) Operation
        5. 7.4.3.5 Dropout
  9. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 Design 1 – Automotive Synchronous 6A Buck Regulator at 2.1MHz
        1. 8.2.1.1 Design Requirements
      2. 8.2.2 Design 2 – Automotive Synchronous 4A Buck Regulator at 2.1MHz
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
          1. 8.2.2.2.1  Custom Design With WEBENCH® Tools
          2. 8.2.2.2.2  Setting the Output Voltage
          3. 8.2.2.2.3  Choosing the Switching Frequency
          4. 8.2.2.2.4  Inductor Selection
          5. 8.2.2.2.5  Output Capacitor Selection
          6. 8.2.2.2.6  Input Capacitor Selection
          7. 8.2.2.2.7  Bootstrap Capacitor
          8. 8.2.2.2.8  VCC Capacitor
          9. 8.2.2.2.9  BIAS Power Connection
          10. 8.2.2.2.10 Feedforward Network
          11. 8.2.2.2.11 Input Voltage UVLO
        3. 8.2.2.3 Application Curves
      3. 8.2.3 Design 3 – Automotive Synchronous 6A Buck Regulator at 400kHz
        1. 8.2.3.1 Design Requirements
        2. 8.2.3.2 Detailed Design Procedure
        3. 8.2.3.3 Application Curves
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
        1. 8.4.1.1 Thermal Design and Layout
      2. 8.4.2 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 Device Support
      1. 9.1.1 サード・パーティ製品に関する免責事項
      2. 9.1.2 Development Support
        1. 9.1.2.1 Custom Design With WEBENCH® Tools
    2. 9.2 Documentation Support
      1. 9.2.1 Related Documentation
    3. 9.3 ドキュメントの更新通知を受け取る方法
    4. 9.4 サポート・リソース
    5. 9.5 Trademarks
    6. 9.6 静電気放電に関する注意事項
    7. 9.7 用語集
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information
    1. 11.1 Tape and Reel 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

7.3.13 Thermal Shutdown

Thermal shutdown prevents the device from extreme junction temperatures by turning off the internal switches when the IC junction temperature exceeds 168°C (typical). Thermal shutdown does not trigger below 158°C. After thermal shutdown occurs, hysteresis prevents the device from switching until the junction temperature drops to approximately 158°C. When the junction temperature falls below 158°C (typical), the converter attempts to soft start.

While the converter is shut down due to high junction temperature, power continues to be provided to VCC. To prevent overheating due to a short circuit applied to VCC, the LDO that provides power for VCC has reduced current limit while the converter is disabled due to high junction temperature. The VCC current limit is reduced to a few milliamperes during thermal shutdown.