SNVSBM6A April   2020  – January 2021 LM5181

PRODUCTION DATA  

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Description (continued)
  6. Pin Configuration and Functions
  7. Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics
    6. 7.6 Typical Characteristics
  8. Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1  Integrated Power MOSFET
      2. 8.3.2  PSR Flyback Modes of Operation
      3. 8.3.3  Setting the Output Voltage
        1. 8.3.3.1 Diode Thermal Compensation
      4. 8.3.4  Control Loop Error Amplifier
      5. 8.3.5  Precision Enable
      6. 8.3.6  Configurable Soft Start
      7. 8.3.7  External Bias Supply
      8. 8.3.8  Minimum On-Time and Off-Time
      9. 8.3.9  Overcurrent Protection
      10. 8.3.10 Thermal Shutdown
    4. 8.4 Device Functional Modes
      1. 8.4.1 Shutdown Mode
      2. 8.4.2 Standby Mode
      3. 8.4.3 Active Mode
  9. Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Applications
      1. 9.2.1 Design 1: Wide VIN, Low IQ PSR Flyback Converter Rated at 5 V, 0.5 A
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
          1. 9.2.1.2.1  Custom Design With WEBENCH® Tools
          2. 9.2.1.2.2  Custom Design With Excel Quickstart Tool
          3. 9.2.1.2.3  Flyback Transformer – T1
          4. 9.2.1.2.4  Flyback Diode – DFLY
          5. 9.2.1.2.5  Zener Clamp Circuit – DF, DCLAMP
          6. 9.2.1.2.6  Output Capacitor – COUT
          7. 9.2.1.2.7  Input Capacitor – CIN
          8. 9.2.1.2.8  Feedback Resistor – RFB
          9. 9.2.1.2.9  Thermal Compensation Resistor – RTC
          10. 9.2.1.2.10 UVLO Resistors – RUV1, RUV2
          11. 9.2.1.2.11 Soft-Start Capacitor – CSS
      2. 9.2.2 Application Curves
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Examples
  12. 12Device and Documentation Support
    1. 12.1 Device Support
      1. 12.1.1 Third-Party Products Disclaimer
      2. 12.1.2 Development Support
        1. 12.1.2.1 Custom Design With WEBENCH® Tools
    2. 12.2 Documentation Support
      1. 12.2.1 Related Documentation
    3. 12.3 Receiving Notification of Documentation Updates
    4. 12.4 Support Resources
    5. 12.5 Trademarks
    6. 12.6 Electrostatic Discharge Caution
    7. 12.7 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

Typical Characteristics

VIN = 24 V, VEN/UVLO = 2 V (unless otherwise stated).

GUID-0DC6C8F9-30A5-4D07-B93D-2E56281ABDEF-low.gifFigure 7-1 Efficiency versus Load
GUID-82F4B11D-F807-49FF-8557-C59A36B2168B-low.gif
See Figure 9-1 IOUT = 0.5 A
Figure 7-3 Primary-side Switching Waveform in BCM
GUID-340BC625-8807-492C-87AA-277DB6145246-low.gif
 
Figure 7-5 Active Quiescent Current versus Temperature
GUID-0B795817-1D9D-4C12-A07A-E989DB57BFFF-low.gifFigure 7-7 RSET Current versus Input Voltage
GUID-87415B66-3D1E-43E1-A461-2DC277B6F446-low.gifFigure 7-9 TC Voltage versus Temperature
GUID-3D0DD50F-06A4-4201-B292-93AA5468AA0A-low.gifFigure 7-11 EN/UVLO Hysteresis Current versus Temperature
GUID-7BB61FE2-6755-46CD-B506-BD0418949A88-low.gifFigure 7-13 Switch Peak Current Limits versus Temperature
GUID-F3C744C7-17A6-4204-BF26-2D6BA520C8DE-low.gifFigure 7-15 Minimum Switching Frequency versus Temperature
GUID-5641DECC-3DEA-4CBD-9FE9-4D3B5FEA06EC-low.gifFigure 7-2 Output Voltage versus Load
GUID-295F004E-5FB3-4B65-92F2-62E2EAD9B95F-low.gif
 
Figure 7-4 Shutdown Quiescent Current versus Temperature
GUID-F44D2E3D-1A16-46D4-8233-518078A2C062-low.gif
VSS/BIAS = 6 V
Figure 7-6 Active Quiescent Current with BIAS versus Temperature
GUID-47DB42E4-7104-4946-849A-3BE249630CA9-low.gifFigure 7-8 RSET Current versus Temperature
GUID-8F39A2AF-530E-4C4B-A8B2-EB7E965A9852-low.gifFigure 7-10 EN/UVLO Threshold Voltages versus Temperature
GUID-14842505-7D68-4183-821B-895A35B9EDF5-low.gifFigure 7-12 MOSFET RDS(on) versus Temperature
GUID-2BBA5ADB-F18A-42F9-A5A5-D0D324B87464-low.gifFigure 7-14 Minimum Switch On-Time versus Temperature
GUID-124A4D24-556E-4442-A707-32DFB233E1E0-low.gifFigure 7-16 Maximum Switching Frequency versus Temperature