SNVS686L March   2011  – June 2025 LMZ22005

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics
    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 Synchronization Input
      2. 6.3.2 Output Overvoltage Protection
      3. 6.3.3 Current Limit
      4. 6.3.4 Thermal Protection
      5. 6.3.5 Prebiased Start-Up
    4. 6.4 Device Functional Modes
      1. 6.4.1 Discontinuous And Continuous Conduction Modes
  8. 7 Application and Implementation
    1. 7.1 Application Information
    2. 7.2 Typical Application
      1. 7.2.1 Design Requirements
      2. 7.2.2 Detailed Design Procedure
        1. 7.2.2.1 Custom Design With WEBENCH® Tools
        2. 7.2.2.2 Design Steps
        3. 7.2.2.3 Enable Divider, RENT, RENB, and RENH Selection
        4. 7.2.2.4 Output Voltage Selection
        5. 7.2.2.5 Soft-start Capacitor Selection
        6. 7.2.2.6 Tracking Supply Divider Option
        7. 7.2.2.7 CO Selection
        8. 7.2.2.8 CIN Selection
        9. 7.2.2.9 Discontinuous and Continuous Conduction Modes Selection
      3. 7.2.3 Application Curves
    3. 7.3 Power Supply Recommendations
    4. 7.4 Layout
      1. 7.4.1 Layout Guidelines
      2. 7.4.2 Layout Examples
      3. 7.4.3 Power Dissipation and Thermal Considerations
      4. 7.4.4 Power Module SMT Guidelines
  9. 8 Device and Documentation Support
    1. 8.1 Device Support
      1. 8.1.1 Development Support
        1. 8.1.1.1 Custom Design With WEBENCH® Tools
    2. 8.2 Documentation Support
      1. 8.2.1 Related Documentation
    3. 8.3 Receiving Notification of Documentation Updates
    4. 8.4 Support Resources
    5. 8.5 Trademarks
    6. 8.6 Electrostatic Discharge Caution
    7. 8.7 Glossary
  10. 9 Revision History
  11. 10Mechanical, Packaging, and Orderable Information

6.3.4 Thermal Protection

The junction temperature of the LMZ22005 must not be allowed to exceed the maximum ratings. Thermal protection is implemented by an internal thermal shutdown circuit which activates at 165°C (typical) causing the device to enter a low power standby state. In this state the main MOSFET remains off causing VO to fall, and additionally the CSS capacitor is discharged to ground. Thermal protection helps prevent catastrophic failures for accidental device overheating. When the junction temperature falls back below 150°C (typical hysteresis = 15°C) the SS pin is released, VO rises smoothly, and normal operation resumes.

Applications requiring maximum output current especially those at high input voltage can require additional derating at elevated temperatures.