SNVS120G April   2000  – May 2019 LM2585

PRODUCTION DATA.  

  1. Features
  2. Applications
  3. Description
    1.     Device Images
      1.      12-V Flyback Regulator Design Example
  4. Revision History
  5. Pin Configurations
  6. Specifications
    1. 6.1  Absolute Maximum Ratings
    2. 6.2  ESD Ratings
    3. 6.3  Recommended Operating Ratings
    4. 6.4  Thermal Information
    5. 6.5  Electrical Characteristics: 3.3 V
    6. 6.6  Electrical Characteristics: 5 V
    7. 6.7  Electrical Characteristics: 12-V
    8. 6.8  Electrical Characteristics: Adjustable
    9. 6.9  Electrical Characteristics: All Versions
    10. 6.10 Typical Characteristics
  7. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Step-Up (Boost) Regulator Operation
  8. Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 Typical Boost Regulator Applications
      2. 8.2.2 Typical Flyback Regulator Applications
        1. 8.2.2.1 Transformer Selection (T)
        2. 8.2.2.2 Transformer Footprints
          1. 8.2.2.2.0.1 T6
          2. 8.2.2.2.0.2 T6
      3. 8.2.3 Design Requirements
      4. 8.2.4 Detailed Design Procedure
        1. 8.2.4.1 Custom Design With WEBENCH® Tools
        2. 8.2.4.2 Programming Output Voltage (Selecting R1 And R2)
        3. 8.2.4.3 Short Circuit Condition
        4. 8.2.4.4 Flyback Regulator Input Capacitors
        5. 8.2.4.5 Switch Voltage Limits
        6. 8.2.4.6 Output Voltage Limitations
        7. 8.2.4.7 Noisy Input Line Condition
        8. 8.2.4.8 Stability
      5. 8.2.5 Application Curve
    3. 8.3 Additional Application Examples
      1. 8.3.1 Test Circuits
  9. Layout
    1. 9.1 Layout Guidelines
    2. 9.2 Heat Sink/Thermal Considerations
  10. 10Device and Documentation Support
    1. 10.1 Device Support
      1. 10.1.1 Third-Party Products Disclaimer
      2. 10.1.2 Development Support
        1. 10.1.2.1 Custom Design With WEBENCH® Tools
    2. 10.2 Receiving Notification of Documentation Updates
    3. 10.3 Community Resources
    4. 10.4 Trademarks
    5. 10.5 Electrostatic Discharge Caution
    6. 10.6 Glossary
  11. 11Mechanical, Packaging, and Orderable Information

Package Options

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

Typical Boost Regulator Applications

Figure 18 through Figure 21 show four typical boost applications)—one fixed and three using the adjustable version of the LM2585. Each drawing contains the part number(s) and manufacturer(s) for every component. For the fixed 12-V output application, the part numbers and manufacturers' names for the inductor are listed in Table 3. For applications with different output voltages, refer to the Switchers Made Simple software.

LM2585 1251551.pngFigure 18. 5-V to 12-V Boost Regulator
LM2585 1251552.pngFigure 19. 12-V to 24-V Boost Regulator
LM2585 1251553.pngFigure 20. 24-V to 36-V Boost Regulator
LM2585 1251554.png
*The LM2585 will require a heat sink in these applications. The size of the heat sink will depend on the maximum ambient temperature. To calculate the thermal resistance of the IC and the size of the heat sink needed, see Heat Sink/Thermal Considerations
Figure 21. 24-V to 48-V Boost Regulator