ZHCSYA6D May   1998  – May 2025 LM138 , LM338

PRODUCTION DATA  

  1.   1
  2. 1 特性
  3. 2 应用
  4. 3 说明
  5. 4 Pin Configuration and Functions
  6. 5 Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 Recommended Operating Conditions
    3. 5.3 Thermal Information
    4. 5.4 Electrical Characteristics: LM138
    5. 5.5 Electrical Characteristics: LM338
    6. 5.6 Typical Characteristics
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1 NPN Darlington Output Drive
      2. 6.3.2 Overload Block
      3. 6.3.3 Programmable Feedback
    4. 6.4 Device Functional Modes
      1. 6.4.1 Normal Operation
      2. 6.4.2 Operation With Low Input Voltage
      3. 6.4.3 Operation at Light Loads
      4. 6.4.4 Operation in Self Protection
  8. 7 Application and Implementation
    1. 7.1 Application Information
    2. 7.2 Typical Applications
      1. 7.2.1 Constant 5-V Regulator
        1. 7.2.1.1 Design Requirements
        2. 7.2.1.2 Detailed Design Procedure
          1. 7.2.1.2.1 External Capacitors
          2. 7.2.1.2.2 Load Regulation
          3. 7.2.1.2.3 Protection Diodes
        3. 7.2.1.3 Application Curves
    3. 7.3 System Examples
    4. 7.4 Power Supply Recommendations
    5. 7.5 Layout
      1. 7.5.1 Layout Guidelines
      2. 7.5.2 Layout Example
  9. 8 Device and Documentation Support
    1. 8.1 接收文档更新通知
    2. 8.2 支持资源
    3. 8.3 Trademarks
    4. 8.4 静电放电警告
    5. 8.5 术语表
  10. 9 Revision History
  11. 10Mechanical, Packaging, and Orderable Information

6.4.2 Operation With Low Input Voltage

The device requires up to 3-V headroom (VI – VO) to operate in regulation. With less headroom, the device may drop out and OUTPUT voltage is INPUT voltage minus drop out voltage.