SNVSCL1 November   2023 LM25185

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Description (continued)
  6. 5 Pin Configuration and Functions
  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 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  Power MOSFET Gate Driver
      2. 7.3.2  PSR Flyback Modes of Operation
      3. 7.3.3  High Voltage VCC Regulator
      4. 7.3.4  Setting the Output Voltage
        1. 7.3.4.1 Diode Thermal Compensation
      5. 7.3.5  Control Loop Error Amplifier
      6. 7.3.6  Precision Enable
      7. 7.3.7  Configurable Soft Start
      8. 7.3.8  Minimum On-Time and Off-Time
      9. 7.3.9  Current Sensing and Overcurrent Protection
      10. 7.3.10 Thermal Shutdown
    4. 7.4 Device Functional Modes
      1. 7.4.1 Shutdown Mode
      2. 7.4.2 Standby Mode
      3. 7.4.3 Active Mode
  9. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 Design 1: Wide VIN, Low IQ PSR Flyback Converter Rated at 16.4 V, 1 A
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1  Custom Design With WEBENCH® Tools
          2. 8.2.1.2.2  Custom Design With Excel Quickstart Tool
          3. 8.2.1.2.3  Flyback Transformer T1 and Current-Sense Resistor (RCS)
          4. 8.2.1.2.4  Flyback Diode – DFLY
          5. 8.2.1.2.5  Leakage Inductance Clamp Circuit – DF, DCLAMP
          6. 8.2.1.2.6  Feedback Resistor – RFB
          7. 8.2.1.2.7  Thermal Compensation Resistor – RTC
          8. 8.2.1.2.8  UVLO Resistors – RUV1, RUV2
          9. 8.2.1.2.9  Soft-Start Capacitor – CSS
          10. 8.2.1.2.10 Compensation Components
        3. 8.2.1.3 Application Curves
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
      2. 8.4.2 Layout Examples
  10. 9 Device and Documentation Support
    1. 9.1 Device Support
      1. 9.1.1 Development Support
        1. 9.1.1.1 Custom Design With WEBENCH® Tools
    2. 9.2 Documentation Support
      1. 9.2.1 Related Documentation
    3. 9.3 Receiving Notification of Documentation Updates
    4. 9.4 Support Resources
    5. 9.5 Trademarks
    6. 9.6 Electrostatic Discharge Caution
    7. 9.7 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

7.3.10 Thermal Shutdown

Thermal shutdown is an integrated self-protection to limit junction temperature and prevent damage related to overheating. Thermal shutdown turns off the device when the junction temperature exceeds 175°C to prevent further power dissipation and temperature rise. Junction temperature decreases after shutdown, and the LM25185 restarts when the junction temperature falls to 165°C.